xref: /titanic_44/usr/src/uts/common/fs/zfs/zfs_vnops.c (revision a1e4879402b1a0a7c410577cff81f1ce31ace7af)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 #include <sys/types.h>
29 #include <sys/param.h>
30 #include <sys/time.h>
31 #include <sys/systm.h>
32 #include <sys/sysmacros.h>
33 #include <sys/resource.h>
34 #include <sys/vfs.h>
35 #include <sys/vfs_opreg.h>
36 #include <sys/vnode.h>
37 #include <sys/file.h>
38 #include <sys/stat.h>
39 #include <sys/kmem.h>
40 #include <sys/taskq.h>
41 #include <sys/uio.h>
42 #include <sys/vmsystm.h>
43 #include <sys/atomic.h>
44 #include <sys/vm.h>
45 #include <vm/seg_vn.h>
46 #include <vm/pvn.h>
47 #include <vm/as.h>
48 #include <sys/mman.h>
49 #include <sys/pathname.h>
50 #include <sys/cmn_err.h>
51 #include <sys/errno.h>
52 #include <sys/unistd.h>
53 #include <sys/zfs_vfsops.h>
54 #include <sys/zfs_dir.h>
55 #include <sys/zfs_acl.h>
56 #include <sys/zfs_ioctl.h>
57 #include <sys/fs/zfs.h>
58 #include <sys/dmu.h>
59 #include <sys/spa.h>
60 #include <sys/txg.h>
61 #include <sys/dbuf.h>
62 #include <sys/zap.h>
63 #include <sys/dirent.h>
64 #include <sys/policy.h>
65 #include <sys/sunddi.h>
66 #include <sys/filio.h>
67 #include "fs/fs_subr.h"
68 #include <sys/zfs_ctldir.h>
69 #include <sys/dnlc.h>
70 #include <sys/zfs_rlock.h>
71 
72 /*
73  * Programming rules.
74  *
75  * Each vnode op performs some logical unit of work.  To do this, the ZPL must
76  * properly lock its in-core state, create a DMU transaction, do the work,
77  * record this work in the intent log (ZIL), commit the DMU transaction,
78  * and wait the the intent log to commit if it's is a synchronous operation.
79  * Morover, the vnode ops must work in both normal and log replay context.
80  * The ordering of events is important to avoid deadlocks and references
81  * to freed memory.  The example below illustrates the following Big Rules:
82  *
83  *  (1) A check must be made in each zfs thread for a mounted file system.
84  *	This is done avoiding races using ZFS_ENTER(zfsvfs).
85  *	A ZFS_EXIT(zfsvfs) is needed before all returns.
86  *
87  *  (2)	VN_RELE() should always be the last thing except for zil_commit()
88  *	(if necessary) and ZFS_EXIT(). This is for 3 reasons:
89  *	First, if it's the last reference, the vnode/znode
90  *	can be freed, so the zp may point to freed memory.  Second, the last
91  *	reference will call zfs_zinactive(), which may induce a lot of work --
92  *	pushing cached pages (which acquires range locks) and syncing out
93  *	cached atime changes.  Third, zfs_zinactive() may require a new tx,
94  *	which could deadlock the system if you were already holding one.
95  *
96  *  (3)	All range locks must be grabbed before calling dmu_tx_assign(),
97  *	as they can span dmu_tx_assign() calls.
98  *
99  *  (4)	Always pass zfsvfs->z_assign as the second argument to dmu_tx_assign().
100  *	In normal operation, this will be TXG_NOWAIT.  During ZIL replay,
101  *	it will be a specific txg.  Either way, dmu_tx_assign() never blocks.
102  *	This is critical because we don't want to block while holding locks.
103  *	Note, in particular, that if a lock is sometimes acquired before
104  *	the tx assigns, and sometimes after (e.g. z_lock), then failing to
105  *	use a non-blocking assign can deadlock the system.  The scenario:
106  *
107  *	Thread A has grabbed a lock before calling dmu_tx_assign().
108  *	Thread B is in an already-assigned tx, and blocks for this lock.
109  *	Thread A calls dmu_tx_assign(TXG_WAIT) and blocks in txg_wait_open()
110  *	forever, because the previous txg can't quiesce until B's tx commits.
111  *
112  *	If dmu_tx_assign() returns ERESTART and zfsvfs->z_assign is TXG_NOWAIT,
113  *	then drop all locks, call dmu_tx_wait(), and try again.
114  *
115  *  (5)	If the operation succeeded, generate the intent log entry for it
116  *	before dropping locks.  This ensures that the ordering of events
117  *	in the intent log matches the order in which they actually occurred.
118  *
119  *  (6)	At the end of each vnode op, the DMU tx must always commit,
120  *	regardless of whether there were any errors.
121  *
122  *  (7)	After dropping all locks, invoke zil_commit(zilog, seq, foid)
123  *	to ensure that synchronous semantics are provided when necessary.
124  *
125  * In general, this is how things should be ordered in each vnode op:
126  *
127  *	ZFS_ENTER(zfsvfs);		// exit if unmounted
128  * top:
129  *	zfs_dirent_lock(&dl, ...)	// lock directory entry (may VN_HOLD())
130  *	rw_enter(...);			// grab any other locks you need
131  *	tx = dmu_tx_create(...);	// get DMU tx
132  *	dmu_tx_hold_*();		// hold each object you might modify
133  *	error = dmu_tx_assign(tx, zfsvfs->z_assign);	// try to assign
134  *	if (error) {
135  *		rw_exit(...);		// drop locks
136  *		zfs_dirent_unlock(dl);	// unlock directory entry
137  *		VN_RELE(...);		// release held vnodes
138  *		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
139  *			dmu_tx_wait(tx);
140  *			dmu_tx_abort(tx);
141  *			goto top;
142  *		}
143  *		dmu_tx_abort(tx);	// abort DMU tx
144  *		ZFS_EXIT(zfsvfs);	// finished in zfs
145  *		return (error);		// really out of space
146  *	}
147  *	error = do_real_work();		// do whatever this VOP does
148  *	if (error == 0)
149  *		zfs_log_*(...);		// on success, make ZIL entry
150  *	dmu_tx_commit(tx);		// commit DMU tx -- error or not
151  *	rw_exit(...);			// drop locks
152  *	zfs_dirent_unlock(dl);		// unlock directory entry
153  *	VN_RELE(...);			// release held vnodes
154  *	zil_commit(zilog, seq, foid);	// synchronous when necessary
155  *	ZFS_EXIT(zfsvfs);		// finished in zfs
156  *	return (error);			// done, report error
157  */
158 /* ARGSUSED */
159 static int
160 zfs_open(vnode_t **vpp, int flag, cred_t *cr)
161 {
162 	znode_t	*zp = VTOZ(*vpp);
163 
164 	/* Keep a count of the synchronous opens in the znode */
165 	if (flag & (FSYNC | FDSYNC))
166 		atomic_inc_32(&zp->z_sync_cnt);
167 	return (0);
168 }
169 
170 /* ARGSUSED */
171 static int
172 zfs_close(vnode_t *vp, int flag, int count, offset_t offset, cred_t *cr)
173 {
174 	znode_t	*zp = VTOZ(vp);
175 
176 	/* Decrement the synchronous opens in the znode */
177 	if (flag & (FSYNC | FDSYNC))
178 		atomic_dec_32(&zp->z_sync_cnt);
179 
180 	/*
181 	 * Clean up any locks held by this process on the vp.
182 	 */
183 	cleanlocks(vp, ddi_get_pid(), 0);
184 	cleanshares(vp, ddi_get_pid());
185 
186 	return (0);
187 }
188 
189 /*
190  * Lseek support for finding holes (cmd == _FIO_SEEK_HOLE) and
191  * data (cmd == _FIO_SEEK_DATA). "off" is an in/out parameter.
192  */
193 static int
194 zfs_holey(vnode_t *vp, int cmd, offset_t *off)
195 {
196 	znode_t	*zp = VTOZ(vp);
197 	uint64_t noff = (uint64_t)*off; /* new offset */
198 	uint64_t file_sz;
199 	int error;
200 	boolean_t hole;
201 
202 	file_sz = zp->z_phys->zp_size;
203 	if (noff >= file_sz)  {
204 		return (ENXIO);
205 	}
206 
207 	if (cmd == _FIO_SEEK_HOLE)
208 		hole = B_TRUE;
209 	else
210 		hole = B_FALSE;
211 
212 	error = dmu_offset_next(zp->z_zfsvfs->z_os, zp->z_id, hole, &noff);
213 
214 	/* end of file? */
215 	if ((error == ESRCH) || (noff > file_sz)) {
216 		/*
217 		 * Handle the virtual hole at the end of file.
218 		 */
219 		if (hole) {
220 			*off = file_sz;
221 			return (0);
222 		}
223 		return (ENXIO);
224 	}
225 
226 	if (noff < *off)
227 		return (error);
228 	*off = noff;
229 	return (error);
230 }
231 
232 /* ARGSUSED */
233 static int
234 zfs_ioctl(vnode_t *vp, int com, intptr_t data, int flag, cred_t *cred,
235     int *rvalp)
236 {
237 	offset_t off;
238 	int error;
239 	zfsvfs_t *zfsvfs;
240 
241 	switch (com) {
242 	    case _FIOFFS:
243 		return (zfs_sync(vp->v_vfsp, 0, cred));
244 
245 		/*
246 		 * The following two ioctls are used by bfu.  Faking out,
247 		 * necessary to avoid bfu errors.
248 		 */
249 	    case _FIOGDIO:
250 	    case _FIOSDIO:
251 		return (0);
252 
253 	    case _FIO_SEEK_DATA:
254 	    case _FIO_SEEK_HOLE:
255 		if (ddi_copyin((void *)data, &off, sizeof (off), flag))
256 			return (EFAULT);
257 
258 		zfsvfs = VTOZ(vp)->z_zfsvfs;
259 		ZFS_ENTER(zfsvfs);
260 
261 		/* offset parameter is in/out */
262 		error = zfs_holey(vp, com, &off);
263 		ZFS_EXIT(zfsvfs);
264 		if (error)
265 			return (error);
266 		if (ddi_copyout(&off, (void *)data, sizeof (off), flag))
267 			return (EFAULT);
268 		return (0);
269 	}
270 	return (ENOTTY);
271 }
272 
273 /*
274  * When a file is memory mapped, we must keep the IO data synchronized
275  * between the DMU cache and the memory mapped pages.  What this means:
276  *
277  * On Write:	If we find a memory mapped page, we write to *both*
278  *		the page and the dmu buffer.
279  *
280  * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when
281  *	the file is memory mapped.
282  */
283 static int
284 mappedwrite(vnode_t *vp, int nbytes, uio_t *uio, dmu_tx_t *tx)
285 {
286 	znode_t	*zp = VTOZ(vp);
287 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
288 	int64_t	start, off;
289 	int len = nbytes;
290 	int error = 0;
291 
292 	start = uio->uio_loffset;
293 	off = start & PAGEOFFSET;
294 	for (start &= PAGEMASK; len > 0; start += PAGESIZE) {
295 		page_t *pp;
296 		uint64_t bytes = MIN(PAGESIZE - off, len);
297 		uint64_t woff = uio->uio_loffset;
298 
299 		/*
300 		 * We don't want a new page to "appear" in the middle of
301 		 * the file update (because it may not get the write
302 		 * update data), so we grab a lock to block
303 		 * zfs_getpage().
304 		 */
305 		rw_enter(&zp->z_map_lock, RW_WRITER);
306 		if (pp = page_lookup(vp, start, SE_SHARED)) {
307 			caddr_t va;
308 
309 			rw_exit(&zp->z_map_lock);
310 			va = ppmapin(pp, PROT_READ | PROT_WRITE, (caddr_t)-1L);
311 			error = uiomove(va+off, bytes, UIO_WRITE, uio);
312 			if (error == 0) {
313 				dmu_write(zfsvfs->z_os, zp->z_id,
314 				    woff, bytes, va+off, tx);
315 			}
316 			ppmapout(va);
317 			page_unlock(pp);
318 		} else {
319 			error = dmu_write_uio(zfsvfs->z_os, zp->z_id,
320 			    uio, bytes, tx);
321 			rw_exit(&zp->z_map_lock);
322 		}
323 		len -= bytes;
324 		off = 0;
325 		if (error)
326 			break;
327 	}
328 	return (error);
329 }
330 
331 /*
332  * When a file is memory mapped, we must keep the IO data synchronized
333  * between the DMU cache and the memory mapped pages.  What this means:
334  *
335  * On Read:	We "read" preferentially from memory mapped pages,
336  *		else we default from the dmu buffer.
337  *
338  * NOTE: We will always "break up" the IO into PAGESIZE uiomoves when
339  *	the file is memory mapped.
340  */
341 static int
342 mappedread(vnode_t *vp, int nbytes, uio_t *uio)
343 {
344 	znode_t *zp = VTOZ(vp);
345 	objset_t *os = zp->z_zfsvfs->z_os;
346 	int64_t	start, off;
347 	int len = nbytes;
348 	int error = 0;
349 
350 	start = uio->uio_loffset;
351 	off = start & PAGEOFFSET;
352 	for (start &= PAGEMASK; len > 0; start += PAGESIZE) {
353 		page_t *pp;
354 		uint64_t bytes = MIN(PAGESIZE - off, len);
355 
356 		if (pp = page_lookup(vp, start, SE_SHARED)) {
357 			caddr_t va;
358 
359 			va = ppmapin(pp, PROT_READ, (caddr_t)-1L);
360 			error = uiomove(va + off, bytes, UIO_READ, uio);
361 			ppmapout(va);
362 			page_unlock(pp);
363 		} else {
364 			error = dmu_read_uio(os, zp->z_id, uio, bytes);
365 		}
366 		len -= bytes;
367 		off = 0;
368 		if (error)
369 			break;
370 	}
371 	return (error);
372 }
373 
374 offset_t zfs_read_chunk_size = 1024 * 1024; /* Tunable */
375 
376 /*
377  * Read bytes from specified file into supplied buffer.
378  *
379  *	IN:	vp	- vnode of file to be read from.
380  *		uio	- structure supplying read location, range info,
381  *			  and return buffer.
382  *		ioflag	- SYNC flags; used to provide FRSYNC semantics.
383  *		cr	- credentials of caller.
384  *
385  *	OUT:	uio	- updated offset and range, buffer filled.
386  *
387  *	RETURN:	0 if success
388  *		error code if failure
389  *
390  * Side Effects:
391  *	vp - atime updated if byte count > 0
392  */
393 /* ARGSUSED */
394 static int
395 zfs_read(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct)
396 {
397 	znode_t		*zp = VTOZ(vp);
398 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
399 	objset_t	*os = zfsvfs->z_os;
400 	ssize_t		n, nbytes;
401 	int		error;
402 	rl_t		*rl;
403 
404 	ZFS_ENTER(zfsvfs);
405 
406 	/*
407 	 * Validate file offset
408 	 */
409 	if (uio->uio_loffset < (offset_t)0) {
410 		ZFS_EXIT(zfsvfs);
411 		return (EINVAL);
412 	}
413 
414 	/*
415 	 * Fasttrack empty reads
416 	 */
417 	if (uio->uio_resid == 0) {
418 		ZFS_EXIT(zfsvfs);
419 		return (0);
420 	}
421 
422 	/*
423 	 * Check for mandatory locks
424 	 */
425 	if (MANDMODE((mode_t)zp->z_phys->zp_mode)) {
426 		if (error = chklock(vp, FREAD,
427 		    uio->uio_loffset, uio->uio_resid, uio->uio_fmode, ct)) {
428 			ZFS_EXIT(zfsvfs);
429 			return (error);
430 		}
431 	}
432 
433 	/*
434 	 * If we're in FRSYNC mode, sync out this znode before reading it.
435 	 */
436 	if (ioflag & FRSYNC)
437 		zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id);
438 
439 	/*
440 	 * Lock the range against changes.
441 	 */
442 	rl = zfs_range_lock(zp, uio->uio_loffset, uio->uio_resid, RL_READER);
443 
444 	/*
445 	 * If we are reading past end-of-file we can skip
446 	 * to the end; but we might still need to set atime.
447 	 */
448 	if (uio->uio_loffset >= zp->z_phys->zp_size) {
449 		error = 0;
450 		goto out;
451 	}
452 
453 	ASSERT(uio->uio_loffset < zp->z_phys->zp_size);
454 	n = MIN(uio->uio_resid, zp->z_phys->zp_size - uio->uio_loffset);
455 
456 	while (n > 0) {
457 		nbytes = MIN(n, zfs_read_chunk_size -
458 		    P2PHASE(uio->uio_loffset, zfs_read_chunk_size));
459 
460 		if (vn_has_cached_data(vp))
461 			error = mappedread(vp, nbytes, uio);
462 		else
463 			error = dmu_read_uio(os, zp->z_id, uio, nbytes);
464 		if (error)
465 			break;
466 
467 		n -= nbytes;
468 	}
469 
470 out:
471 	zfs_range_unlock(rl);
472 
473 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
474 	ZFS_EXIT(zfsvfs);
475 	return (error);
476 }
477 
478 /*
479  * Fault in the pages of the first n bytes specified by the uio structure.
480  * 1 byte in each page is touched and the uio struct is unmodified.
481  * Any error will exit this routine as this is only a best
482  * attempt to get the pages resident. This is a copy of ufs_trans_touch().
483  */
484 static void
485 zfs_prefault_write(ssize_t n, struct uio *uio)
486 {
487 	struct iovec *iov;
488 	ulong_t cnt, incr;
489 	caddr_t p;
490 	uint8_t tmp;
491 
492 	iov = uio->uio_iov;
493 
494 	while (n) {
495 		cnt = MIN(iov->iov_len, n);
496 		if (cnt == 0) {
497 			/* empty iov entry */
498 			iov++;
499 			continue;
500 		}
501 		n -= cnt;
502 		/*
503 		 * touch each page in this segment.
504 		 */
505 		p = iov->iov_base;
506 		while (cnt) {
507 			switch (uio->uio_segflg) {
508 			case UIO_USERSPACE:
509 			case UIO_USERISPACE:
510 				if (fuword8(p, &tmp))
511 					return;
512 				break;
513 			case UIO_SYSSPACE:
514 				if (kcopy(p, &tmp, 1))
515 					return;
516 				break;
517 			}
518 			incr = MIN(cnt, PAGESIZE);
519 			p += incr;
520 			cnt -= incr;
521 		}
522 		/*
523 		 * touch the last byte in case it straddles a page.
524 		 */
525 		p--;
526 		switch (uio->uio_segflg) {
527 		case UIO_USERSPACE:
528 		case UIO_USERISPACE:
529 			if (fuword8(p, &tmp))
530 				return;
531 			break;
532 		case UIO_SYSSPACE:
533 			if (kcopy(p, &tmp, 1))
534 				return;
535 			break;
536 		}
537 		iov++;
538 	}
539 }
540 
541 /*
542  * Write the bytes to a file.
543  *
544  *	IN:	vp	- vnode of file to be written to.
545  *		uio	- structure supplying write location, range info,
546  *			  and data buffer.
547  *		ioflag	- FAPPEND flag set if in append mode.
548  *		cr	- credentials of caller.
549  *
550  *	OUT:	uio	- updated offset and range.
551  *
552  *	RETURN:	0 if success
553  *		error code if failure
554  *
555  * Timestamps:
556  *	vp - ctime|mtime updated if byte count > 0
557  */
558 /* ARGSUSED */
559 static int
560 zfs_write(vnode_t *vp, uio_t *uio, int ioflag, cred_t *cr, caller_context_t *ct)
561 {
562 	znode_t		*zp = VTOZ(vp);
563 	rlim64_t	limit = uio->uio_llimit;
564 	ssize_t		start_resid = uio->uio_resid;
565 	ssize_t		tx_bytes;
566 	uint64_t	end_size;
567 	dmu_tx_t	*tx;
568 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
569 	zilog_t		*zilog = zfsvfs->z_log;
570 	offset_t	woff;
571 	ssize_t		n, nbytes;
572 	rl_t		*rl;
573 	int		max_blksz = zfsvfs->z_max_blksz;
574 	int		error;
575 
576 	/*
577 	 * Fasttrack empty write
578 	 */
579 	n = start_resid;
580 	if (n == 0)
581 		return (0);
582 
583 	if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T)
584 		limit = MAXOFFSET_T;
585 
586 	ZFS_ENTER(zfsvfs);
587 
588 	/*
589 	 * Pre-fault the pages to ensure slow (eg NFS) pages
590 	 * don't hold up txg.
591 	 */
592 	zfs_prefault_write(n, uio);
593 
594 	/*
595 	 * If in append mode, set the io offset pointer to eof.
596 	 */
597 	if (ioflag & FAPPEND) {
598 		/*
599 		 * Range lock for a file append:
600 		 * The value for the start of range will be determined by
601 		 * zfs_range_lock() (to guarantee append semantics).
602 		 * If this write will cause the block size to increase,
603 		 * zfs_range_lock() will lock the entire file, so we must
604 		 * later reduce the range after we grow the block size.
605 		 */
606 		rl = zfs_range_lock(zp, 0, n, RL_APPEND);
607 		if (rl->r_len == UINT64_MAX) {
608 			/* overlocked, zp_size can't change */
609 			woff = uio->uio_loffset = zp->z_phys->zp_size;
610 		} else {
611 			woff = uio->uio_loffset = rl->r_off;
612 		}
613 	} else {
614 		woff = uio->uio_loffset;
615 		/*
616 		 * Validate file offset
617 		 */
618 		if (woff < 0) {
619 			ZFS_EXIT(zfsvfs);
620 			return (EINVAL);
621 		}
622 
623 		/*
624 		 * If we need to grow the block size then zfs_range_lock()
625 		 * will lock a wider range than we request here.
626 		 * Later after growing the block size we reduce the range.
627 		 */
628 		rl = zfs_range_lock(zp, woff, n, RL_WRITER);
629 	}
630 
631 	if (woff >= limit) {
632 		zfs_range_unlock(rl);
633 		ZFS_EXIT(zfsvfs);
634 		return (EFBIG);
635 	}
636 
637 	if ((woff + n) > limit || woff > (limit - n))
638 		n = limit - woff;
639 
640 	/*
641 	 * Check for mandatory locks
642 	 */
643 	if (MANDMODE((mode_t)zp->z_phys->zp_mode) &&
644 	    (error = chklock(vp, FWRITE, woff, n, uio->uio_fmode, ct)) != 0) {
645 		zfs_range_unlock(rl);
646 		ZFS_EXIT(zfsvfs);
647 		return (error);
648 	}
649 	end_size = MAX(zp->z_phys->zp_size, woff + n);
650 
651 	/*
652 	 * Write the file in reasonable size chunks.  Each chunk is written
653 	 * in a separate transaction; this keeps the intent log records small
654 	 * and allows us to do more fine-grained space accounting.
655 	 */
656 	while (n > 0) {
657 		/*
658 		 * Start a transaction.
659 		 */
660 		woff = uio->uio_loffset;
661 		tx = dmu_tx_create(zfsvfs->z_os);
662 		dmu_tx_hold_bonus(tx, zp->z_id);
663 		dmu_tx_hold_write(tx, zp->z_id, woff, MIN(n, max_blksz));
664 		error = dmu_tx_assign(tx, zfsvfs->z_assign);
665 		if (error) {
666 			if (error == ERESTART &&
667 			    zfsvfs->z_assign == TXG_NOWAIT) {
668 				dmu_tx_wait(tx);
669 				dmu_tx_abort(tx);
670 				continue;
671 			}
672 			dmu_tx_abort(tx);
673 			break;
674 		}
675 
676 		/*
677 		 * If zfs_range_lock() over-locked we grow the blocksize
678 		 * and then reduce the lock range.  This will only happen
679 		 * on the first iteration since zfs_range_reduce() will
680 		 * shrink down r_len to the appropriate size.
681 		 */
682 		if (rl->r_len == UINT64_MAX) {
683 			uint64_t new_blksz;
684 
685 			if (zp->z_blksz > max_blksz) {
686 				ASSERT(!ISP2(zp->z_blksz));
687 				new_blksz = MIN(end_size, SPA_MAXBLOCKSIZE);
688 			} else {
689 				new_blksz = MIN(end_size, max_blksz);
690 			}
691 			zfs_grow_blocksize(zp, new_blksz, tx);
692 			zfs_range_reduce(rl, woff, n);
693 		}
694 
695 		/*
696 		 * XXX - should we really limit each write to z_max_blksz?
697 		 * Perhaps we should use SPA_MAXBLOCKSIZE chunks?
698 		 */
699 		nbytes = MIN(n, max_blksz - P2PHASE(woff, max_blksz));
700 		rw_enter(&zp->z_map_lock, RW_READER);
701 
702 		tx_bytes = uio->uio_resid;
703 		if (vn_has_cached_data(vp)) {
704 			rw_exit(&zp->z_map_lock);
705 			error = mappedwrite(vp, nbytes, uio, tx);
706 		} else {
707 			error = dmu_write_uio(zfsvfs->z_os, zp->z_id,
708 			    uio, nbytes, tx);
709 			rw_exit(&zp->z_map_lock);
710 		}
711 		tx_bytes -= uio->uio_resid;
712 
713 		/*
714 		 * If we made no progress, we're done.  If we made even
715 		 * partial progress, update the znode and ZIL accordingly.
716 		 */
717 		if (tx_bytes == 0) {
718 			dmu_tx_commit(tx);
719 			ASSERT(error != 0);
720 			break;
721 		}
722 
723 		/*
724 		 * Clear Set-UID/Set-GID bits on successful write if not
725 		 * privileged and at least one of the excute bits is set.
726 		 *
727 		 * It would be nice to to this after all writes have
728 		 * been done, but that would still expose the ISUID/ISGID
729 		 * to another app after the partial write is committed.
730 		 */
731 		mutex_enter(&zp->z_acl_lock);
732 		if ((zp->z_phys->zp_mode & (S_IXUSR | (S_IXUSR >> 3) |
733 		    (S_IXUSR >> 6))) != 0 &&
734 		    (zp->z_phys->zp_mode & (S_ISUID | S_ISGID)) != 0 &&
735 		    secpolicy_vnode_setid_retain(cr,
736 		    (zp->z_phys->zp_mode & S_ISUID) != 0 &&
737 		    zp->z_phys->zp_uid == 0) != 0) {
738 			    zp->z_phys->zp_mode &= ~(S_ISUID | S_ISGID);
739 		}
740 		mutex_exit(&zp->z_acl_lock);
741 
742 		/*
743 		 * Update time stamp.  NOTE: This marks the bonus buffer as
744 		 * dirty, so we don't have to do it again for zp_size.
745 		 */
746 		zfs_time_stamper(zp, CONTENT_MODIFIED, tx);
747 
748 		/*
749 		 * Update the file size (zp_size) if it has changed;
750 		 * account for possible concurrent updates.
751 		 */
752 		while ((end_size = zp->z_phys->zp_size) < uio->uio_loffset)
753 			(void) atomic_cas_64(&zp->z_phys->zp_size, end_size,
754 			    uio->uio_loffset);
755 		zfs_log_write(zilog, tx, TX_WRITE, zp, woff, tx_bytes, ioflag);
756 		dmu_tx_commit(tx);
757 
758 		if (error != 0)
759 			break;
760 		ASSERT(tx_bytes == nbytes);
761 		n -= nbytes;
762 	}
763 
764 	zfs_range_unlock(rl);
765 
766 	/*
767 	 * If we're in replay mode, or we made no progress, return error.
768 	 * Otherwise, it's at least a partial write, so it's successful.
769 	 */
770 	if (zfsvfs->z_assign >= TXG_INITIAL || uio->uio_resid == start_resid) {
771 		ZFS_EXIT(zfsvfs);
772 		return (error);
773 	}
774 
775 	if (ioflag & (FSYNC | FDSYNC))
776 		zil_commit(zilog, zp->z_last_itx, zp->z_id);
777 
778 	ZFS_EXIT(zfsvfs);
779 	return (0);
780 }
781 
782 void
783 zfs_get_done(dmu_buf_t *db, void *vzgd)
784 {
785 	zgd_t *zgd = (zgd_t *)vzgd;
786 	rl_t *rl = zgd->zgd_rl;
787 	vnode_t *vp = ZTOV(rl->r_zp);
788 
789 	dmu_buf_rele(db, vzgd);
790 	zfs_range_unlock(rl);
791 	VN_RELE(vp);
792 	zil_add_vdev(zgd->zgd_zilog, DVA_GET_VDEV(BP_IDENTITY(zgd->zgd_bp)));
793 	kmem_free(zgd, sizeof (zgd_t));
794 }
795 
796 /*
797  * Get data to generate a TX_WRITE intent log record.
798  */
799 int
800 zfs_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio)
801 {
802 	zfsvfs_t *zfsvfs = arg;
803 	objset_t *os = zfsvfs->z_os;
804 	znode_t *zp;
805 	uint64_t off = lr->lr_offset;
806 	dmu_buf_t *db;
807 	rl_t *rl;
808 	zgd_t *zgd;
809 	int dlen = lr->lr_length;		/* length of user data */
810 	int error = 0;
811 
812 	ASSERT(zio);
813 	ASSERT(dlen != 0);
814 
815 	/*
816 	 * Nothing to do if the file has been removed
817 	 */
818 	if (zfs_zget(zfsvfs, lr->lr_foid, &zp) != 0)
819 		return (ENOENT);
820 	if (zp->z_unlinked) {
821 		VN_RELE(ZTOV(zp));
822 		return (ENOENT);
823 	}
824 
825 	/*
826 	 * Write records come in two flavors: immediate and indirect.
827 	 * For small writes it's cheaper to store the data with the
828 	 * log record (immediate); for large writes it's cheaper to
829 	 * sync the data and get a pointer to it (indirect) so that
830 	 * we don't have to write the data twice.
831 	 */
832 	if (buf != NULL) { /* immediate write */
833 		rl = zfs_range_lock(zp, off, dlen, RL_READER);
834 		/* test for truncation needs to be done while range locked */
835 		if (off >= zp->z_phys->zp_size) {
836 			error = ENOENT;
837 			goto out;
838 		}
839 		VERIFY(0 == dmu_read(os, lr->lr_foid, off, dlen, buf));
840 	} else { /* indirect write */
841 		uint64_t boff; /* block starting offset */
842 
843 		/*
844 		 * Have to lock the whole block to ensure when it's
845 		 * written out and it's checksum is being calculated
846 		 * that no one can change the data. We need to re-check
847 		 * blocksize after we get the lock in case it's changed!
848 		 */
849 		for (;;) {
850 			if (ISP2(zp->z_blksz)) {
851 				boff = P2ALIGN_TYPED(off, zp->z_blksz,
852 				    uint64_t);
853 			} else {
854 				boff = 0;
855 			}
856 			dlen = zp->z_blksz;
857 			rl = zfs_range_lock(zp, boff, dlen, RL_READER);
858 			if (zp->z_blksz == dlen)
859 				break;
860 			zfs_range_unlock(rl);
861 		}
862 		/* test for truncation needs to be done while range locked */
863 		if (off >= zp->z_phys->zp_size) {
864 			error = ENOENT;
865 			goto out;
866 		}
867 		zgd = (zgd_t *)kmem_alloc(sizeof (zgd_t), KM_SLEEP);
868 		zgd->zgd_rl = rl;
869 		zgd->zgd_zilog = zfsvfs->z_log;
870 		zgd->zgd_bp = &lr->lr_blkptr;
871 		VERIFY(0 == dmu_buf_hold(os, lr->lr_foid, boff, zgd, &db));
872 		ASSERT(boff == db->db_offset);
873 		lr->lr_blkoff = off - boff;
874 		error = dmu_sync(zio, db, &lr->lr_blkptr,
875 		    lr->lr_common.lrc_txg, zfs_get_done, zgd);
876 		ASSERT(error == EEXIST || lr->lr_length <= zp->z_blksz);
877 		if (error == 0) {
878 			zil_add_vdev(zfsvfs->z_log,
879 			    DVA_GET_VDEV(BP_IDENTITY(&lr->lr_blkptr)));
880 		}
881 		/*
882 		 * If we get EINPROGRESS, then we need to wait for a
883 		 * write IO initiated by dmu_sync() to complete before
884 		 * we can release this dbuf.  We will finish everything
885 		 * up in the zfs_get_done() callback.
886 		 */
887 		if (error == EINPROGRESS)
888 			return (0);
889 		dmu_buf_rele(db, zgd);
890 		kmem_free(zgd, sizeof (zgd_t));
891 	}
892 out:
893 	zfs_range_unlock(rl);
894 	VN_RELE(ZTOV(zp));
895 	return (error);
896 }
897 
898 /*ARGSUSED*/
899 static int
900 zfs_access(vnode_t *vp, int mode, int flags, cred_t *cr)
901 {
902 	znode_t *zp = VTOZ(vp);
903 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
904 	int error;
905 
906 	ZFS_ENTER(zfsvfs);
907 	error = zfs_zaccess_rwx(zp, mode, cr);
908 	ZFS_EXIT(zfsvfs);
909 	return (error);
910 }
911 
912 /*
913  * Lookup an entry in a directory, or an extended attribute directory.
914  * If it exists, return a held vnode reference for it.
915  *
916  *	IN:	dvp	- vnode of directory to search.
917  *		nm	- name of entry to lookup.
918  *		pnp	- full pathname to lookup [UNUSED].
919  *		flags	- LOOKUP_XATTR set if looking for an attribute.
920  *		rdir	- root directory vnode [UNUSED].
921  *		cr	- credentials of caller.
922  *
923  *	OUT:	vpp	- vnode of located entry, NULL if not found.
924  *
925  *	RETURN:	0 if success
926  *		error code if failure
927  *
928  * Timestamps:
929  *	NA
930  */
931 /* ARGSUSED */
932 static int
933 zfs_lookup(vnode_t *dvp, char *nm, vnode_t **vpp, struct pathname *pnp,
934     int flags, vnode_t *rdir, cred_t *cr)
935 {
936 
937 	znode_t *zdp = VTOZ(dvp);
938 	zfsvfs_t *zfsvfs = zdp->z_zfsvfs;
939 	int	error;
940 
941 	ZFS_ENTER(zfsvfs);
942 
943 	*vpp = NULL;
944 
945 	if (flags & LOOKUP_XATTR) {
946 		/*
947 		 * If the xattr property is off, refuse the lookup request.
948 		 */
949 		if (!(zfsvfs->z_vfs->vfs_flag & VFS_XATTR)) {
950 			ZFS_EXIT(zfsvfs);
951 			return (EINVAL);
952 		}
953 
954 		/*
955 		 * We don't allow recursive attributes..
956 		 * Maybe someday we will.
957 		 */
958 		if (zdp->z_phys->zp_flags & ZFS_XATTR) {
959 			ZFS_EXIT(zfsvfs);
960 			return (EINVAL);
961 		}
962 
963 		if (error = zfs_get_xattrdir(VTOZ(dvp), vpp, cr, flags)) {
964 			ZFS_EXIT(zfsvfs);
965 			return (error);
966 		}
967 
968 		/*
969 		 * Do we have permission to get into attribute directory?
970 		 */
971 
972 		if (error = zfs_zaccess(VTOZ(*vpp), ACE_EXECUTE, cr)) {
973 			VN_RELE(*vpp);
974 		}
975 
976 		ZFS_EXIT(zfsvfs);
977 		return (error);
978 	}
979 
980 	if (dvp->v_type != VDIR) {
981 		ZFS_EXIT(zfsvfs);
982 		return (ENOTDIR);
983 	}
984 
985 	/*
986 	 * Check accessibility of directory.
987 	 */
988 
989 	if (error = zfs_zaccess(zdp, ACE_EXECUTE, cr)) {
990 		ZFS_EXIT(zfsvfs);
991 		return (error);
992 	}
993 
994 	if ((error = zfs_dirlook(zdp, nm, vpp)) == 0) {
995 
996 		/*
997 		 * Convert device special files
998 		 */
999 		if (IS_DEVVP(*vpp)) {
1000 			vnode_t	*svp;
1001 
1002 			svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
1003 			VN_RELE(*vpp);
1004 			if (svp == NULL)
1005 				error = ENOSYS;
1006 			else
1007 				*vpp = svp;
1008 		}
1009 	}
1010 
1011 	ZFS_EXIT(zfsvfs);
1012 	return (error);
1013 }
1014 
1015 /*
1016  * Attempt to create a new entry in a directory.  If the entry
1017  * already exists, truncate the file if permissible, else return
1018  * an error.  Return the vp of the created or trunc'd file.
1019  *
1020  *	IN:	dvp	- vnode of directory to put new file entry in.
1021  *		name	- name of new file entry.
1022  *		vap	- attributes of new file.
1023  *		excl	- flag indicating exclusive or non-exclusive mode.
1024  *		mode	- mode to open file with.
1025  *		cr	- credentials of caller.
1026  *		flag	- large file flag [UNUSED].
1027  *
1028  *	OUT:	vpp	- vnode of created or trunc'd entry.
1029  *
1030  *	RETURN:	0 if success
1031  *		error code if failure
1032  *
1033  * Timestamps:
1034  *	dvp - ctime|mtime updated if new entry created
1035  *	 vp - ctime|mtime always, atime if new
1036  */
1037 /* ARGSUSED */
1038 static int
1039 zfs_create(vnode_t *dvp, char *name, vattr_t *vap, vcexcl_t excl,
1040     int mode, vnode_t **vpp, cred_t *cr, int flag)
1041 {
1042 	znode_t		*zp, *dzp = VTOZ(dvp);
1043 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1044 	zilog_t		*zilog = zfsvfs->z_log;
1045 	objset_t	*os = zfsvfs->z_os;
1046 	zfs_dirlock_t	*dl;
1047 	dmu_tx_t	*tx;
1048 	int		error;
1049 	uint64_t	zoid;
1050 
1051 	ZFS_ENTER(zfsvfs);
1052 
1053 top:
1054 	*vpp = NULL;
1055 
1056 	if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr))
1057 		vap->va_mode &= ~VSVTX;
1058 
1059 	if (*name == '\0') {
1060 		/*
1061 		 * Null component name refers to the directory itself.
1062 		 */
1063 		VN_HOLD(dvp);
1064 		zp = dzp;
1065 		dl = NULL;
1066 		error = 0;
1067 	} else {
1068 		/* possible VN_HOLD(zp) */
1069 		if (error = zfs_dirent_lock(&dl, dzp, name, &zp, 0)) {
1070 			if (strcmp(name, "..") == 0)
1071 				error = EISDIR;
1072 			ZFS_EXIT(zfsvfs);
1073 			return (error);
1074 		}
1075 	}
1076 
1077 	zoid = zp ? zp->z_id : -1ULL;
1078 
1079 	if (zp == NULL) {
1080 		/*
1081 		 * Create a new file object and update the directory
1082 		 * to reference it.
1083 		 */
1084 		if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) {
1085 			goto out;
1086 		}
1087 
1088 		/*
1089 		 * We only support the creation of regular files in
1090 		 * extended attribute directories.
1091 		 */
1092 		if ((dzp->z_phys->zp_flags & ZFS_XATTR) &&
1093 		    (vap->va_type != VREG)) {
1094 			error = EINVAL;
1095 			goto out;
1096 		}
1097 
1098 		tx = dmu_tx_create(os);
1099 		dmu_tx_hold_bonus(tx, DMU_NEW_OBJECT);
1100 		dmu_tx_hold_bonus(tx, dzp->z_id);
1101 		dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
1102 		if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE)
1103 			dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
1104 			    0, SPA_MAXBLOCKSIZE);
1105 		error = dmu_tx_assign(tx, zfsvfs->z_assign);
1106 		if (error) {
1107 			zfs_dirent_unlock(dl);
1108 			if (error == ERESTART &&
1109 			    zfsvfs->z_assign == TXG_NOWAIT) {
1110 				dmu_tx_wait(tx);
1111 				dmu_tx_abort(tx);
1112 				goto top;
1113 			}
1114 			dmu_tx_abort(tx);
1115 			ZFS_EXIT(zfsvfs);
1116 			return (error);
1117 		}
1118 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0);
1119 		ASSERT(zp->z_id == zoid);
1120 		(void) zfs_link_create(dl, zp, tx, ZNEW);
1121 		zfs_log_create(zilog, tx, TX_CREATE, dzp, zp, name);
1122 		dmu_tx_commit(tx);
1123 	} else {
1124 		/*
1125 		 * A directory entry already exists for this name.
1126 		 */
1127 		/*
1128 		 * Can't truncate an existing file if in exclusive mode.
1129 		 */
1130 		if (excl == EXCL) {
1131 			error = EEXIST;
1132 			goto out;
1133 		}
1134 		/*
1135 		 * Can't open a directory for writing.
1136 		 */
1137 		if ((ZTOV(zp)->v_type == VDIR) && (mode & S_IWRITE)) {
1138 			error = EISDIR;
1139 			goto out;
1140 		}
1141 		/*
1142 		 * Verify requested access to file.
1143 		 */
1144 		if (mode && (error = zfs_zaccess_rwx(zp, mode, cr))) {
1145 			goto out;
1146 		}
1147 
1148 		mutex_enter(&dzp->z_lock);
1149 		dzp->z_seq++;
1150 		mutex_exit(&dzp->z_lock);
1151 
1152 		/*
1153 		 * Truncate regular files if requested.
1154 		 */
1155 		if ((ZTOV(zp)->v_type == VREG) &&
1156 		    (zp->z_phys->zp_size != 0) &&
1157 		    (vap->va_mask & AT_SIZE) && (vap->va_size == 0)) {
1158 			error = zfs_freesp(zp, 0, 0, mode, TRUE);
1159 			if (error == ERESTART &&
1160 			    zfsvfs->z_assign == TXG_NOWAIT) {
1161 				/* NB: we already did dmu_tx_wait() */
1162 				zfs_dirent_unlock(dl);
1163 				VN_RELE(ZTOV(zp));
1164 				goto top;
1165 			}
1166 		}
1167 	}
1168 out:
1169 
1170 	if (dl)
1171 		zfs_dirent_unlock(dl);
1172 
1173 	if (error) {
1174 		if (zp)
1175 			VN_RELE(ZTOV(zp));
1176 	} else {
1177 		*vpp = ZTOV(zp);
1178 		/*
1179 		 * If vnode is for a device return a specfs vnode instead.
1180 		 */
1181 		if (IS_DEVVP(*vpp)) {
1182 			struct vnode *svp;
1183 
1184 			svp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
1185 			VN_RELE(*vpp);
1186 			if (svp == NULL) {
1187 				error = ENOSYS;
1188 			}
1189 			*vpp = svp;
1190 		}
1191 	}
1192 
1193 	ZFS_EXIT(zfsvfs);
1194 	return (error);
1195 }
1196 
1197 /*
1198  * Remove an entry from a directory.
1199  *
1200  *	IN:	dvp	- vnode of directory to remove entry from.
1201  *		name	- name of entry to remove.
1202  *		cr	- credentials of caller.
1203  *
1204  *	RETURN:	0 if success
1205  *		error code if failure
1206  *
1207  * Timestamps:
1208  *	dvp - ctime|mtime
1209  *	 vp - ctime (if nlink > 0)
1210  */
1211 static int
1212 zfs_remove(vnode_t *dvp, char *name, cred_t *cr)
1213 {
1214 	znode_t		*zp, *dzp = VTOZ(dvp);
1215 	znode_t		*xzp = NULL;
1216 	vnode_t		*vp;
1217 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1218 	zilog_t		*zilog = zfsvfs->z_log;
1219 	uint64_t	acl_obj, xattr_obj;
1220 	zfs_dirlock_t	*dl;
1221 	dmu_tx_t	*tx;
1222 	boolean_t	may_delete_now, delete_now = FALSE;
1223 	boolean_t	unlinked;
1224 	int		error;
1225 
1226 	ZFS_ENTER(zfsvfs);
1227 
1228 top:
1229 	/*
1230 	 * Attempt to lock directory; fail if entry doesn't exist.
1231 	 */
1232 	if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) {
1233 		ZFS_EXIT(zfsvfs);
1234 		return (error);
1235 	}
1236 
1237 	vp = ZTOV(zp);
1238 
1239 	if (error = zfs_zaccess_delete(dzp, zp, cr)) {
1240 		goto out;
1241 	}
1242 
1243 	/*
1244 	 * Need to use rmdir for removing directories.
1245 	 */
1246 	if (vp->v_type == VDIR) {
1247 		error = EPERM;
1248 		goto out;
1249 	}
1250 
1251 	vnevent_remove(vp);
1252 
1253 	dnlc_remove(dvp, name);
1254 
1255 	mutex_enter(&vp->v_lock);
1256 	may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp);
1257 	mutex_exit(&vp->v_lock);
1258 
1259 	/*
1260 	 * We may delete the znode now, or we may put it in the unlinked set;
1261 	 * it depends on whether we're the last link, and on whether there are
1262 	 * other holds on the vnode.  So we dmu_tx_hold() the right things to
1263 	 * allow for either case.
1264 	 */
1265 	tx = dmu_tx_create(zfsvfs->z_os);
1266 	dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
1267 	dmu_tx_hold_bonus(tx, zp->z_id);
1268 	if (may_delete_now)
1269 		dmu_tx_hold_free(tx, zp->z_id, 0, DMU_OBJECT_END);
1270 
1271 	/* are there any extended attributes? */
1272 	if ((xattr_obj = zp->z_phys->zp_xattr) != 0) {
1273 		/* XXX - do we need this if we are deleting? */
1274 		dmu_tx_hold_bonus(tx, xattr_obj);
1275 	}
1276 
1277 	/* are there any additional acls */
1278 	if ((acl_obj = zp->z_phys->zp_acl.z_acl_extern_obj) != 0 &&
1279 	    may_delete_now)
1280 		dmu_tx_hold_free(tx, acl_obj, 0, DMU_OBJECT_END);
1281 
1282 	/* charge as an update -- would be nice not to charge at all */
1283 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
1284 
1285 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1286 	if (error) {
1287 		zfs_dirent_unlock(dl);
1288 		VN_RELE(vp);
1289 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1290 			dmu_tx_wait(tx);
1291 			dmu_tx_abort(tx);
1292 			goto top;
1293 		}
1294 		dmu_tx_abort(tx);
1295 		ZFS_EXIT(zfsvfs);
1296 		return (error);
1297 	}
1298 
1299 	/*
1300 	 * Remove the directory entry.
1301 	 */
1302 	error = zfs_link_destroy(dl, zp, tx, 0, &unlinked);
1303 
1304 	if (error) {
1305 		dmu_tx_commit(tx);
1306 		goto out;
1307 	}
1308 
1309 	if (unlinked) {
1310 		mutex_enter(&vp->v_lock);
1311 		delete_now = may_delete_now &&
1312 		    vp->v_count == 1 && !vn_has_cached_data(vp) &&
1313 		    zp->z_phys->zp_xattr == xattr_obj &&
1314 		    zp->z_phys->zp_acl.z_acl_extern_obj == acl_obj;
1315 		mutex_exit(&vp->v_lock);
1316 	}
1317 
1318 	if (delete_now) {
1319 		if (zp->z_phys->zp_xattr) {
1320 			error = zfs_zget(zfsvfs, zp->z_phys->zp_xattr, &xzp);
1321 			ASSERT3U(error, ==, 0);
1322 			ASSERT3U(xzp->z_phys->zp_links, ==, 2);
1323 			dmu_buf_will_dirty(xzp->z_dbuf, tx);
1324 			mutex_enter(&xzp->z_lock);
1325 			xzp->z_unlinked = 1;
1326 			xzp->z_phys->zp_links = 0;
1327 			mutex_exit(&xzp->z_lock);
1328 			zfs_unlinked_add(xzp, tx);
1329 			zp->z_phys->zp_xattr = 0; /* probably unnecessary */
1330 		}
1331 		mutex_enter(&zp->z_lock);
1332 		mutex_enter(&vp->v_lock);
1333 		vp->v_count--;
1334 		ASSERT3U(vp->v_count, ==, 0);
1335 		mutex_exit(&vp->v_lock);
1336 		mutex_exit(&zp->z_lock);
1337 		zfs_znode_delete(zp, tx);
1338 		VFS_RELE(zfsvfs->z_vfs);
1339 	} else if (unlinked) {
1340 		zfs_unlinked_add(zp, tx);
1341 	}
1342 
1343 	zfs_log_remove(zilog, tx, TX_REMOVE, dzp, name);
1344 
1345 	dmu_tx_commit(tx);
1346 out:
1347 	zfs_dirent_unlock(dl);
1348 
1349 	if (!delete_now) {
1350 		VN_RELE(vp);
1351 	} else if (xzp) {
1352 		/* this rele delayed to prevent nesting transactions */
1353 		VN_RELE(ZTOV(xzp));
1354 	}
1355 
1356 	ZFS_EXIT(zfsvfs);
1357 	return (error);
1358 }
1359 
1360 /*
1361  * Create a new directory and insert it into dvp using the name
1362  * provided.  Return a pointer to the inserted directory.
1363  *
1364  *	IN:	dvp	- vnode of directory to add subdir to.
1365  *		dirname	- name of new directory.
1366  *		vap	- attributes of new directory.
1367  *		cr	- credentials of caller.
1368  *
1369  *	OUT:	vpp	- vnode of created directory.
1370  *
1371  *	RETURN:	0 if success
1372  *		error code if failure
1373  *
1374  * Timestamps:
1375  *	dvp - ctime|mtime updated
1376  *	 vp - ctime|mtime|atime updated
1377  */
1378 static int
1379 zfs_mkdir(vnode_t *dvp, char *dirname, vattr_t *vap, vnode_t **vpp, cred_t *cr)
1380 {
1381 	znode_t		*zp, *dzp = VTOZ(dvp);
1382 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1383 	zilog_t		*zilog = zfsvfs->z_log;
1384 	zfs_dirlock_t	*dl;
1385 	uint64_t	zoid = 0;
1386 	dmu_tx_t	*tx;
1387 	int		error;
1388 
1389 	ASSERT(vap->va_type == VDIR);
1390 
1391 	ZFS_ENTER(zfsvfs);
1392 
1393 	if (dzp->z_phys->zp_flags & ZFS_XATTR) {
1394 		ZFS_EXIT(zfsvfs);
1395 		return (EINVAL);
1396 	}
1397 top:
1398 	*vpp = NULL;
1399 
1400 	/*
1401 	 * First make sure the new directory doesn't exist.
1402 	 */
1403 	if (error = zfs_dirent_lock(&dl, dzp, dirname, &zp, ZNEW)) {
1404 		ZFS_EXIT(zfsvfs);
1405 		return (error);
1406 	}
1407 
1408 	if (error = zfs_zaccess(dzp, ACE_ADD_SUBDIRECTORY, cr)) {
1409 		zfs_dirent_unlock(dl);
1410 		ZFS_EXIT(zfsvfs);
1411 		return (error);
1412 	}
1413 
1414 	/*
1415 	 * Add a new entry to the directory.
1416 	 */
1417 	tx = dmu_tx_create(zfsvfs->z_os);
1418 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, dirname);
1419 	dmu_tx_hold_zap(tx, DMU_NEW_OBJECT, FALSE, NULL);
1420 	if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE)
1421 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
1422 		    0, SPA_MAXBLOCKSIZE);
1423 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1424 	if (error) {
1425 		zfs_dirent_unlock(dl);
1426 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1427 			dmu_tx_wait(tx);
1428 			dmu_tx_abort(tx);
1429 			goto top;
1430 		}
1431 		dmu_tx_abort(tx);
1432 		ZFS_EXIT(zfsvfs);
1433 		return (error);
1434 	}
1435 
1436 	/*
1437 	 * Create new node.
1438 	 */
1439 	zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0);
1440 
1441 	/*
1442 	 * Now put new name in parent dir.
1443 	 */
1444 	(void) zfs_link_create(dl, zp, tx, ZNEW);
1445 
1446 	*vpp = ZTOV(zp);
1447 
1448 	zfs_log_create(zilog, tx, TX_MKDIR, dzp, zp, dirname);
1449 	dmu_tx_commit(tx);
1450 
1451 	zfs_dirent_unlock(dl);
1452 
1453 	ZFS_EXIT(zfsvfs);
1454 	return (0);
1455 }
1456 
1457 /*
1458  * Remove a directory subdir entry.  If the current working
1459  * directory is the same as the subdir to be removed, the
1460  * remove will fail.
1461  *
1462  *	IN:	dvp	- vnode of directory to remove from.
1463  *		name	- name of directory to be removed.
1464  *		cwd	- vnode of current working directory.
1465  *		cr	- credentials of caller.
1466  *
1467  *	RETURN:	0 if success
1468  *		error code if failure
1469  *
1470  * Timestamps:
1471  *	dvp - ctime|mtime updated
1472  */
1473 static int
1474 zfs_rmdir(vnode_t *dvp, char *name, vnode_t *cwd, cred_t *cr)
1475 {
1476 	znode_t		*dzp = VTOZ(dvp);
1477 	znode_t		*zp;
1478 	vnode_t		*vp;
1479 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
1480 	zilog_t		*zilog = zfsvfs->z_log;
1481 	zfs_dirlock_t	*dl;
1482 	dmu_tx_t	*tx;
1483 	int		error;
1484 
1485 	ZFS_ENTER(zfsvfs);
1486 
1487 top:
1488 	zp = NULL;
1489 
1490 	/*
1491 	 * Attempt to lock directory; fail if entry doesn't exist.
1492 	 */
1493 	if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZEXISTS)) {
1494 		ZFS_EXIT(zfsvfs);
1495 		return (error);
1496 	}
1497 
1498 	vp = ZTOV(zp);
1499 
1500 	if (error = zfs_zaccess_delete(dzp, zp, cr)) {
1501 		goto out;
1502 	}
1503 
1504 	if (vp->v_type != VDIR) {
1505 		error = ENOTDIR;
1506 		goto out;
1507 	}
1508 
1509 	if (vp == cwd) {
1510 		error = EINVAL;
1511 		goto out;
1512 	}
1513 
1514 	vnevent_rmdir(vp);
1515 
1516 	/*
1517 	 * Grab a lock on the directory to make sure that noone is
1518 	 * trying to add (or lookup) entries while we are removing it.
1519 	 */
1520 	rw_enter(&zp->z_name_lock, RW_WRITER);
1521 
1522 	/*
1523 	 * Grab a lock on the parent pointer to make sure we play well
1524 	 * with the treewalk and directory rename code.
1525 	 */
1526 	rw_enter(&zp->z_parent_lock, RW_WRITER);
1527 
1528 	tx = dmu_tx_create(zfsvfs->z_os);
1529 	dmu_tx_hold_zap(tx, dzp->z_id, FALSE, name);
1530 	dmu_tx_hold_bonus(tx, zp->z_id);
1531 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
1532 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
1533 	if (error) {
1534 		rw_exit(&zp->z_parent_lock);
1535 		rw_exit(&zp->z_name_lock);
1536 		zfs_dirent_unlock(dl);
1537 		VN_RELE(vp);
1538 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
1539 			dmu_tx_wait(tx);
1540 			dmu_tx_abort(tx);
1541 			goto top;
1542 		}
1543 		dmu_tx_abort(tx);
1544 		ZFS_EXIT(zfsvfs);
1545 		return (error);
1546 	}
1547 
1548 	error = zfs_link_destroy(dl, zp, tx, 0, NULL);
1549 
1550 	if (error == 0)
1551 		zfs_log_remove(zilog, tx, TX_RMDIR, dzp, name);
1552 
1553 	dmu_tx_commit(tx);
1554 
1555 	rw_exit(&zp->z_parent_lock);
1556 	rw_exit(&zp->z_name_lock);
1557 out:
1558 	zfs_dirent_unlock(dl);
1559 
1560 	VN_RELE(vp);
1561 
1562 	ZFS_EXIT(zfsvfs);
1563 	return (error);
1564 }
1565 
1566 /*
1567  * Read as many directory entries as will fit into the provided
1568  * buffer from the given directory cursor position (specified in
1569  * the uio structure.
1570  *
1571  *	IN:	vp	- vnode of directory to read.
1572  *		uio	- structure supplying read location, range info,
1573  *			  and return buffer.
1574  *		cr	- credentials of caller.
1575  *
1576  *	OUT:	uio	- updated offset and range, buffer filled.
1577  *		eofp	- set to true if end-of-file detected.
1578  *
1579  *	RETURN:	0 if success
1580  *		error code if failure
1581  *
1582  * Timestamps:
1583  *	vp - atime updated
1584  *
1585  * Note that the low 4 bits of the cookie returned by zap is always zero.
1586  * This allows us to use the low range for "special" directory entries:
1587  * We use 0 for '.', and 1 for '..'.  If this is the root of the filesystem,
1588  * we use the offset 2 for the '.zfs' directory.
1589  */
1590 /* ARGSUSED */
1591 static int
1592 zfs_readdir(vnode_t *vp, uio_t *uio, cred_t *cr, int *eofp)
1593 {
1594 	znode_t		*zp = VTOZ(vp);
1595 	iovec_t		*iovp;
1596 	dirent64_t	*odp;
1597 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
1598 	objset_t	*os;
1599 	caddr_t		outbuf;
1600 	size_t		bufsize;
1601 	zap_cursor_t	zc;
1602 	zap_attribute_t	zap;
1603 	uint_t		bytes_wanted;
1604 	uint64_t	offset; /* must be unsigned; checks for < 1 */
1605 	int		local_eof;
1606 	int		outcount;
1607 	int		error;
1608 	uint8_t		prefetch;
1609 
1610 	ZFS_ENTER(zfsvfs);
1611 
1612 	/*
1613 	 * If we are not given an eof variable,
1614 	 * use a local one.
1615 	 */
1616 	if (eofp == NULL)
1617 		eofp = &local_eof;
1618 
1619 	/*
1620 	 * Check for valid iov_len.
1621 	 */
1622 	if (uio->uio_iov->iov_len <= 0) {
1623 		ZFS_EXIT(zfsvfs);
1624 		return (EINVAL);
1625 	}
1626 
1627 	/*
1628 	 * Quit if directory has been removed (posix)
1629 	 */
1630 	if ((*eofp = zp->z_unlinked) != 0) {
1631 		ZFS_EXIT(zfsvfs);
1632 		return (0);
1633 	}
1634 
1635 	error = 0;
1636 	os = zfsvfs->z_os;
1637 	offset = uio->uio_loffset;
1638 	prefetch = zp->z_zn_prefetch;
1639 
1640 	/*
1641 	 * Initialize the iterator cursor.
1642 	 */
1643 	if (offset <= 3) {
1644 		/*
1645 		 * Start iteration from the beginning of the directory.
1646 		 */
1647 		zap_cursor_init(&zc, os, zp->z_id);
1648 	} else {
1649 		/*
1650 		 * The offset is a serialized cursor.
1651 		 */
1652 		zap_cursor_init_serialized(&zc, os, zp->z_id, offset);
1653 	}
1654 
1655 	/*
1656 	 * Get space to change directory entries into fs independent format.
1657 	 */
1658 	iovp = uio->uio_iov;
1659 	bytes_wanted = iovp->iov_len;
1660 	if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1) {
1661 		bufsize = bytes_wanted;
1662 		outbuf = kmem_alloc(bufsize, KM_SLEEP);
1663 		odp = (struct dirent64 *)outbuf;
1664 	} else {
1665 		bufsize = bytes_wanted;
1666 		odp = (struct dirent64 *)iovp->iov_base;
1667 	}
1668 
1669 	/*
1670 	 * Transform to file-system independent format
1671 	 */
1672 	outcount = 0;
1673 	while (outcount < bytes_wanted) {
1674 		ino64_t objnum;
1675 		ushort_t reclen;
1676 		off64_t *next;
1677 
1678 		/*
1679 		 * Special case `.', `..', and `.zfs'.
1680 		 */
1681 		if (offset == 0) {
1682 			(void) strcpy(zap.za_name, ".");
1683 			objnum = zp->z_id;
1684 		} else if (offset == 1) {
1685 			(void) strcpy(zap.za_name, "..");
1686 			objnum = zp->z_phys->zp_parent;
1687 		} else if (offset == 2 && zfs_show_ctldir(zp)) {
1688 			(void) strcpy(zap.za_name, ZFS_CTLDIR_NAME);
1689 			objnum = ZFSCTL_INO_ROOT;
1690 		} else {
1691 			/*
1692 			 * Grab next entry.
1693 			 */
1694 			if (error = zap_cursor_retrieve(&zc, &zap)) {
1695 				if ((*eofp = (error == ENOENT)) != 0)
1696 					break;
1697 				else
1698 					goto update;
1699 			}
1700 
1701 			if (zap.za_integer_length != 8 ||
1702 			    zap.za_num_integers != 1) {
1703 				cmn_err(CE_WARN, "zap_readdir: bad directory "
1704 				    "entry, obj = %lld, offset = %lld\n",
1705 				    (u_longlong_t)zp->z_id,
1706 				    (u_longlong_t)offset);
1707 				error = ENXIO;
1708 				goto update;
1709 			}
1710 
1711 			objnum = ZFS_DIRENT_OBJ(zap.za_first_integer);
1712 			/*
1713 			 * MacOS X can extract the object type here such as:
1714 			 * uint8_t type = ZFS_DIRENT_TYPE(zap.za_first_integer);
1715 			 */
1716 		}
1717 		reclen = DIRENT64_RECLEN(strlen(zap.za_name));
1718 
1719 		/*
1720 		 * Will this entry fit in the buffer?
1721 		 */
1722 		if (outcount + reclen > bufsize) {
1723 			/*
1724 			 * Did we manage to fit anything in the buffer?
1725 			 */
1726 			if (!outcount) {
1727 				error = EINVAL;
1728 				goto update;
1729 			}
1730 			break;
1731 		}
1732 		/*
1733 		 * Add this entry:
1734 		 */
1735 		odp->d_ino = objnum;
1736 		odp->d_reclen = reclen;
1737 		/* NOTE: d_off is the offset for the *next* entry */
1738 		next = &(odp->d_off);
1739 		(void) strncpy(odp->d_name, zap.za_name,
1740 		    DIRENT64_NAMELEN(reclen));
1741 		outcount += reclen;
1742 		odp = (dirent64_t *)((intptr_t)odp + reclen);
1743 
1744 		ASSERT(outcount <= bufsize);
1745 
1746 		/* Prefetch znode */
1747 		if (prefetch)
1748 			dmu_prefetch(os, objnum, 0, 0);
1749 
1750 		/*
1751 		 * Move to the next entry, fill in the previous offset.
1752 		 */
1753 		if (offset > 2 || (offset == 2 && !zfs_show_ctldir(zp))) {
1754 			zap_cursor_advance(&zc);
1755 			offset = zap_cursor_serialize(&zc);
1756 		} else {
1757 			offset += 1;
1758 		}
1759 		*next = offset;
1760 	}
1761 	zp->z_zn_prefetch = B_FALSE; /* a lookup will re-enable pre-fetching */
1762 
1763 	if (uio->uio_segflg == UIO_SYSSPACE && uio->uio_iovcnt == 1) {
1764 		iovp->iov_base += outcount;
1765 		iovp->iov_len -= outcount;
1766 		uio->uio_resid -= outcount;
1767 	} else if (error = uiomove(outbuf, (long)outcount, UIO_READ, uio)) {
1768 		/*
1769 		 * Reset the pointer.
1770 		 */
1771 		offset = uio->uio_loffset;
1772 	}
1773 
1774 update:
1775 	zap_cursor_fini(&zc);
1776 	if (uio->uio_segflg != UIO_SYSSPACE || uio->uio_iovcnt != 1)
1777 		kmem_free(outbuf, bufsize);
1778 
1779 	if (error == ENOENT)
1780 		error = 0;
1781 
1782 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
1783 
1784 	uio->uio_loffset = offset;
1785 	ZFS_EXIT(zfsvfs);
1786 	return (error);
1787 }
1788 
1789 static int
1790 zfs_fsync(vnode_t *vp, int syncflag, cred_t *cr)
1791 {
1792 	znode_t	*zp = VTOZ(vp);
1793 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
1794 
1795 	/*
1796 	 * Regardless of whether this is required for standards conformance,
1797 	 * this is the logical behavior when fsync() is called on a file with
1798 	 * dirty pages.  We use B_ASYNC since the ZIL transactions are already
1799 	 * going to be pushed out as part of the zil_commit().
1800 	 */
1801 	if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) &&
1802 	    (vp->v_type == VREG) && !(IS_SWAPVP(vp)))
1803 		(void) VOP_PUTPAGE(vp, (offset_t)0, (size_t)0, B_ASYNC, cr);
1804 
1805 	ZFS_ENTER(zfsvfs);
1806 	zil_commit(zfsvfs->z_log, zp->z_last_itx, zp->z_id);
1807 	ZFS_EXIT(zfsvfs);
1808 	return (0);
1809 }
1810 
1811 /*
1812  * Get the requested file attributes and place them in the provided
1813  * vattr structure.
1814  *
1815  *	IN:	vp	- vnode of file.
1816  *		vap	- va_mask identifies requested attributes.
1817  *		flags	- [UNUSED]
1818  *		cr	- credentials of caller.
1819  *
1820  *	OUT:	vap	- attribute values.
1821  *
1822  *	RETURN:	0 (always succeeds)
1823  */
1824 /* ARGSUSED */
1825 static int
1826 zfs_getattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr)
1827 {
1828 	znode_t *zp = VTOZ(vp);
1829 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
1830 	znode_phys_t *pzp = zp->z_phys;
1831 	int	error;
1832 
1833 	ZFS_ENTER(zfsvfs);
1834 
1835 	/*
1836 	 * Return all attributes.  It's cheaper to provide the answer
1837 	 * than to determine whether we were asked the question.
1838 	 */
1839 	mutex_enter(&zp->z_lock);
1840 
1841 	vap->va_type = vp->v_type;
1842 	vap->va_mode = pzp->zp_mode & MODEMASK;
1843 	vap->va_uid = zp->z_phys->zp_uid;
1844 	vap->va_gid = zp->z_phys->zp_gid;
1845 	vap->va_fsid = zp->z_zfsvfs->z_vfs->vfs_dev;
1846 	vap->va_nodeid = zp->z_id;
1847 	vap->va_nlink = MIN(pzp->zp_links, UINT32_MAX);	/* nlink_t limit! */
1848 	vap->va_size = pzp->zp_size;
1849 	vap->va_rdev = vp->v_rdev;
1850 	vap->va_seq = zp->z_seq;
1851 
1852 	ZFS_TIME_DECODE(&vap->va_atime, pzp->zp_atime);
1853 	ZFS_TIME_DECODE(&vap->va_mtime, pzp->zp_mtime);
1854 	ZFS_TIME_DECODE(&vap->va_ctime, pzp->zp_ctime);
1855 
1856 	/*
1857 	 * If ACL is trivial don't bother looking for ACE_READ_ATTRIBUTES.
1858 	 * Also, if we are the owner don't bother, since owner should
1859 	 * always be allowed to read basic attributes of file.
1860 	 */
1861 	if (!(zp->z_phys->zp_flags & ZFS_ACL_TRIVIAL) &&
1862 	    (zp->z_phys->zp_uid != crgetuid(cr))) {
1863 		if (error = zfs_zaccess(zp, ACE_READ_ATTRIBUTES, cr)) {
1864 			mutex_exit(&zp->z_lock);
1865 			ZFS_EXIT(zfsvfs);
1866 			return (error);
1867 		}
1868 	}
1869 
1870 	mutex_exit(&zp->z_lock);
1871 
1872 	dmu_object_size_from_db(zp->z_dbuf, &vap->va_blksize, &vap->va_nblocks);
1873 
1874 	if (zp->z_blksz == 0) {
1875 		/*
1876 		 * Block size hasn't been set; suggest maximal I/O transfers.
1877 		 */
1878 		vap->va_blksize = zfsvfs->z_max_blksz;
1879 	}
1880 
1881 	ZFS_EXIT(zfsvfs);
1882 	return (0);
1883 }
1884 
1885 /*
1886  * Set the file attributes to the values contained in the
1887  * vattr structure.
1888  *
1889  *	IN:	vp	- vnode of file to be modified.
1890  *		vap	- new attribute values.
1891  *		flags	- ATTR_UTIME set if non-default time values provided.
1892  *		cr	- credentials of caller.
1893  *
1894  *	RETURN:	0 if success
1895  *		error code if failure
1896  *
1897  * Timestamps:
1898  *	vp - ctime updated, mtime updated if size changed.
1899  */
1900 /* ARGSUSED */
1901 static int
1902 zfs_setattr(vnode_t *vp, vattr_t *vap, int flags, cred_t *cr,
1903 	caller_context_t *ct)
1904 {
1905 	struct znode	*zp = VTOZ(vp);
1906 	znode_phys_t	*pzp = zp->z_phys;
1907 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
1908 	zilog_t		*zilog = zfsvfs->z_log;
1909 	dmu_tx_t	*tx;
1910 	vattr_t		oldva;
1911 	uint_t		mask = vap->va_mask;
1912 	uint_t		saved_mask;
1913 	int		trim_mask = 0;
1914 	uint64_t	new_mode;
1915 	znode_t		*attrzp;
1916 	int		need_policy = FALSE;
1917 	int		err;
1918 
1919 	if (mask == 0)
1920 		return (0);
1921 
1922 	if (mask & AT_NOSET)
1923 		return (EINVAL);
1924 
1925 	if (mask & AT_SIZE && vp->v_type == VDIR)
1926 		return (EISDIR);
1927 
1928 	if (mask & AT_SIZE && vp->v_type != VREG && vp->v_type != VFIFO)
1929 		return (EINVAL);
1930 
1931 	ZFS_ENTER(zfsvfs);
1932 
1933 top:
1934 	attrzp = NULL;
1935 
1936 	if (zfsvfs->z_vfs->vfs_flag & VFS_RDONLY) {
1937 		ZFS_EXIT(zfsvfs);
1938 		return (EROFS);
1939 	}
1940 
1941 	/*
1942 	 * First validate permissions
1943 	 */
1944 
1945 	if (mask & AT_SIZE) {
1946 		err = zfs_zaccess(zp, ACE_WRITE_DATA, cr);
1947 		if (err) {
1948 			ZFS_EXIT(zfsvfs);
1949 			return (err);
1950 		}
1951 		/*
1952 		 * XXX - Note, we are not providing any open
1953 		 * mode flags here (like FNDELAY), so we may
1954 		 * block if there are locks present... this
1955 		 * should be addressed in openat().
1956 		 */
1957 		do {
1958 			err = zfs_freesp(zp, vap->va_size, 0, 0, FALSE);
1959 			/* NB: we already did dmu_tx_wait() if necessary */
1960 		} while (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT);
1961 		if (err) {
1962 			ZFS_EXIT(zfsvfs);
1963 			return (err);
1964 		}
1965 	}
1966 
1967 	if (mask & (AT_ATIME|AT_MTIME))
1968 		need_policy = zfs_zaccess_v4_perm(zp, ACE_WRITE_ATTRIBUTES, cr);
1969 
1970 	if (mask & (AT_UID|AT_GID)) {
1971 		int	idmask = (mask & (AT_UID|AT_GID));
1972 		int	take_owner;
1973 		int	take_group;
1974 
1975 		/*
1976 		 * NOTE: even if a new mode is being set,
1977 		 * we may clear S_ISUID/S_ISGID bits.
1978 		 */
1979 
1980 		if (!(mask & AT_MODE))
1981 			vap->va_mode = pzp->zp_mode;
1982 
1983 		/*
1984 		 * Take ownership or chgrp to group we are a member of
1985 		 */
1986 
1987 		take_owner = (mask & AT_UID) && (vap->va_uid == crgetuid(cr));
1988 		take_group = (mask & AT_GID) && groupmember(vap->va_gid, cr);
1989 
1990 		/*
1991 		 * If both AT_UID and AT_GID are set then take_owner and
1992 		 * take_group must both be set in order to allow taking
1993 		 * ownership.
1994 		 *
1995 		 * Otherwise, send the check through secpolicy_vnode_setattr()
1996 		 *
1997 		 */
1998 
1999 		if (((idmask == (AT_UID|AT_GID)) && take_owner && take_group) ||
2000 		    ((idmask == AT_UID) && take_owner) ||
2001 		    ((idmask == AT_GID) && take_group)) {
2002 			if (zfs_zaccess_v4_perm(zp, ACE_WRITE_OWNER, cr) == 0) {
2003 				/*
2004 				 * Remove setuid/setgid for non-privileged users
2005 				 */
2006 				secpolicy_setid_clear(vap, cr);
2007 				trim_mask = (mask & (AT_UID|AT_GID));
2008 			} else {
2009 				need_policy =  TRUE;
2010 			}
2011 		} else {
2012 			need_policy =  TRUE;
2013 		}
2014 	}
2015 
2016 	mutex_enter(&zp->z_lock);
2017 	oldva.va_mode = pzp->zp_mode;
2018 	oldva.va_uid = zp->z_phys->zp_uid;
2019 	oldva.va_gid = zp->z_phys->zp_gid;
2020 	mutex_exit(&zp->z_lock);
2021 
2022 	if (mask & AT_MODE) {
2023 		if (zfs_zaccess_v4_perm(zp, ACE_WRITE_ACL, cr) == 0) {
2024 			err = secpolicy_setid_setsticky_clear(vp, vap,
2025 			    &oldva, cr);
2026 			if (err) {
2027 				ZFS_EXIT(zfsvfs);
2028 				return (err);
2029 			}
2030 			trim_mask |= AT_MODE;
2031 		} else {
2032 			need_policy = TRUE;
2033 		}
2034 	}
2035 
2036 	if (need_policy) {
2037 		/*
2038 		 * If trim_mask is set then take ownership
2039 		 * has been granted or write_acl is present and user
2040 		 * has the ability to modify mode.  In that case remove
2041 		 * UID|GID and or MODE from mask so that
2042 		 * secpolicy_vnode_setattr() doesn't revoke it.
2043 		 */
2044 
2045 		if (trim_mask) {
2046 			saved_mask = vap->va_mask;
2047 			vap->va_mask &= ~trim_mask;
2048 
2049 		}
2050 		err = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags,
2051 		    (int (*)(void *, int, cred_t *))zfs_zaccess_rwx, zp);
2052 		if (err) {
2053 			ZFS_EXIT(zfsvfs);
2054 			return (err);
2055 		}
2056 
2057 		if (trim_mask)
2058 			vap->va_mask |= saved_mask;
2059 	}
2060 
2061 	/*
2062 	 * secpolicy_vnode_setattr, or take ownership may have
2063 	 * changed va_mask
2064 	 */
2065 	mask = vap->va_mask;
2066 
2067 	tx = dmu_tx_create(zfsvfs->z_os);
2068 	dmu_tx_hold_bonus(tx, zp->z_id);
2069 
2070 	if (mask & AT_MODE) {
2071 		uint64_t pmode = pzp->zp_mode;
2072 
2073 		new_mode = (pmode & S_IFMT) | (vap->va_mode & ~S_IFMT);
2074 
2075 		if (zp->z_phys->zp_acl.z_acl_extern_obj)
2076 			dmu_tx_hold_write(tx,
2077 			    pzp->zp_acl.z_acl_extern_obj, 0, SPA_MAXBLOCKSIZE);
2078 		else
2079 			dmu_tx_hold_write(tx, DMU_NEW_OBJECT,
2080 			    0, ZFS_ACL_SIZE(MAX_ACL_SIZE));
2081 	}
2082 
2083 	if ((mask & (AT_UID | AT_GID)) && zp->z_phys->zp_xattr != 0) {
2084 		err = zfs_zget(zp->z_zfsvfs, zp->z_phys->zp_xattr, &attrzp);
2085 		if (err) {
2086 			dmu_tx_abort(tx);
2087 			ZFS_EXIT(zfsvfs);
2088 			return (err);
2089 		}
2090 		dmu_tx_hold_bonus(tx, attrzp->z_id);
2091 	}
2092 
2093 	err = dmu_tx_assign(tx, zfsvfs->z_assign);
2094 	if (err) {
2095 		if (attrzp)
2096 			VN_RELE(ZTOV(attrzp));
2097 		if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2098 			dmu_tx_wait(tx);
2099 			dmu_tx_abort(tx);
2100 			goto top;
2101 		}
2102 		dmu_tx_abort(tx);
2103 		ZFS_EXIT(zfsvfs);
2104 		return (err);
2105 	}
2106 
2107 	dmu_buf_will_dirty(zp->z_dbuf, tx);
2108 
2109 	/*
2110 	 * Set each attribute requested.
2111 	 * We group settings according to the locks they need to acquire.
2112 	 *
2113 	 * Note: you cannot set ctime directly, although it will be
2114 	 * updated as a side-effect of calling this function.
2115 	 */
2116 
2117 	mutex_enter(&zp->z_lock);
2118 
2119 	if (mask & AT_MODE) {
2120 		err = zfs_acl_chmod_setattr(zp, new_mode, tx);
2121 		ASSERT3U(err, ==, 0);
2122 	}
2123 
2124 	if (attrzp)
2125 		mutex_enter(&attrzp->z_lock);
2126 
2127 	if (mask & AT_UID) {
2128 		zp->z_phys->zp_uid = (uint64_t)vap->va_uid;
2129 		if (attrzp) {
2130 			attrzp->z_phys->zp_uid = (uint64_t)vap->va_uid;
2131 		}
2132 	}
2133 
2134 	if (mask & AT_GID) {
2135 		zp->z_phys->zp_gid = (uint64_t)vap->va_gid;
2136 		if (attrzp)
2137 			attrzp->z_phys->zp_gid = (uint64_t)vap->va_gid;
2138 	}
2139 
2140 	if (attrzp)
2141 		mutex_exit(&attrzp->z_lock);
2142 
2143 	if (mask & AT_ATIME)
2144 		ZFS_TIME_ENCODE(&vap->va_atime, pzp->zp_atime);
2145 
2146 	if (mask & AT_MTIME)
2147 		ZFS_TIME_ENCODE(&vap->va_mtime, pzp->zp_mtime);
2148 
2149 	if (mask & AT_SIZE)
2150 		zfs_time_stamper_locked(zp, CONTENT_MODIFIED, tx);
2151 	else if (mask != 0)
2152 		zfs_time_stamper_locked(zp, STATE_CHANGED, tx);
2153 
2154 	if (mask != 0)
2155 		zfs_log_setattr(zilog, tx, TX_SETATTR, zp, vap, mask);
2156 
2157 	mutex_exit(&zp->z_lock);
2158 
2159 	if (attrzp)
2160 		VN_RELE(ZTOV(attrzp));
2161 
2162 	dmu_tx_commit(tx);
2163 
2164 	ZFS_EXIT(zfsvfs);
2165 	return (err);
2166 }
2167 
2168 typedef struct zfs_zlock {
2169 	krwlock_t	*zl_rwlock;	/* lock we acquired */
2170 	znode_t		*zl_znode;	/* znode we held */
2171 	struct zfs_zlock *zl_next;	/* next in list */
2172 } zfs_zlock_t;
2173 
2174 /*
2175  * Drop locks and release vnodes that were held by zfs_rename_lock().
2176  */
2177 static void
2178 zfs_rename_unlock(zfs_zlock_t **zlpp)
2179 {
2180 	zfs_zlock_t *zl;
2181 
2182 	while ((zl = *zlpp) != NULL) {
2183 		if (zl->zl_znode != NULL)
2184 			VN_RELE(ZTOV(zl->zl_znode));
2185 		rw_exit(zl->zl_rwlock);
2186 		*zlpp = zl->zl_next;
2187 		kmem_free(zl, sizeof (*zl));
2188 	}
2189 }
2190 
2191 /*
2192  * Search back through the directory tree, using the ".." entries.
2193  * Lock each directory in the chain to prevent concurrent renames.
2194  * Fail any attempt to move a directory into one of its own descendants.
2195  * XXX - z_parent_lock can overlap with map or grow locks
2196  */
2197 static int
2198 zfs_rename_lock(znode_t *szp, znode_t *tdzp, znode_t *sdzp, zfs_zlock_t **zlpp)
2199 {
2200 	zfs_zlock_t	*zl;
2201 	znode_t		*zp = tdzp;
2202 	uint64_t	rootid = zp->z_zfsvfs->z_root;
2203 	uint64_t	*oidp = &zp->z_id;
2204 	krwlock_t	*rwlp = &szp->z_parent_lock;
2205 	krw_t		rw = RW_WRITER;
2206 
2207 	/*
2208 	 * First pass write-locks szp and compares to zp->z_id.
2209 	 * Later passes read-lock zp and compare to zp->z_parent.
2210 	 */
2211 	do {
2212 		if (!rw_tryenter(rwlp, rw)) {
2213 			/*
2214 			 * Another thread is renaming in this path.
2215 			 * Note that if we are a WRITER, we don't have any
2216 			 * parent_locks held yet.
2217 			 */
2218 			if (rw == RW_READER && zp->z_id > szp->z_id) {
2219 				/*
2220 				 * Drop our locks and restart
2221 				 */
2222 				zfs_rename_unlock(&zl);
2223 				*zlpp = NULL;
2224 				zp = tdzp;
2225 				oidp = &zp->z_id;
2226 				rwlp = &szp->z_parent_lock;
2227 				rw = RW_WRITER;
2228 				continue;
2229 			} else {
2230 				/*
2231 				 * Wait for other thread to drop its locks
2232 				 */
2233 				rw_enter(rwlp, rw);
2234 			}
2235 		}
2236 
2237 		zl = kmem_alloc(sizeof (*zl), KM_SLEEP);
2238 		zl->zl_rwlock = rwlp;
2239 		zl->zl_znode = NULL;
2240 		zl->zl_next = *zlpp;
2241 		*zlpp = zl;
2242 
2243 		if (*oidp == szp->z_id)		/* We're a descendant of szp */
2244 			return (EINVAL);
2245 
2246 		if (*oidp == rootid)		/* We've hit the top */
2247 			return (0);
2248 
2249 		if (rw == RW_READER) {		/* i.e. not the first pass */
2250 			int error = zfs_zget(zp->z_zfsvfs, *oidp, &zp);
2251 			if (error)
2252 				return (error);
2253 			zl->zl_znode = zp;
2254 		}
2255 		oidp = &zp->z_phys->zp_parent;
2256 		rwlp = &zp->z_parent_lock;
2257 		rw = RW_READER;
2258 
2259 	} while (zp->z_id != sdzp->z_id);
2260 
2261 	return (0);
2262 }
2263 
2264 /*
2265  * Move an entry from the provided source directory to the target
2266  * directory.  Change the entry name as indicated.
2267  *
2268  *	IN:	sdvp	- Source directory containing the "old entry".
2269  *		snm	- Old entry name.
2270  *		tdvp	- Target directory to contain the "new entry".
2271  *		tnm	- New entry name.
2272  *		cr	- credentials of caller.
2273  *
2274  *	RETURN:	0 if success
2275  *		error code if failure
2276  *
2277  * Timestamps:
2278  *	sdvp,tdvp - ctime|mtime updated
2279  */
2280 static int
2281 zfs_rename(vnode_t *sdvp, char *snm, vnode_t *tdvp, char *tnm, cred_t *cr)
2282 {
2283 	znode_t		*tdzp, *szp, *tzp;
2284 	znode_t		*sdzp = VTOZ(sdvp);
2285 	zfsvfs_t	*zfsvfs = sdzp->z_zfsvfs;
2286 	zilog_t		*zilog = zfsvfs->z_log;
2287 	vnode_t		*realvp;
2288 	zfs_dirlock_t	*sdl, *tdl;
2289 	dmu_tx_t	*tx;
2290 	zfs_zlock_t	*zl;
2291 	int		cmp, serr, terr, error;
2292 
2293 	ZFS_ENTER(zfsvfs);
2294 
2295 	/*
2296 	 * Make sure we have the real vp for the target directory.
2297 	 */
2298 	if (VOP_REALVP(tdvp, &realvp) == 0)
2299 		tdvp = realvp;
2300 
2301 	if (tdvp->v_vfsp != sdvp->v_vfsp) {
2302 		ZFS_EXIT(zfsvfs);
2303 		return (EXDEV);
2304 	}
2305 
2306 	tdzp = VTOZ(tdvp);
2307 top:
2308 	szp = NULL;
2309 	tzp = NULL;
2310 	zl = NULL;
2311 
2312 	/*
2313 	 * This is to prevent the creation of links into attribute space
2314 	 * by renaming a linked file into/outof an attribute directory.
2315 	 * See the comment in zfs_link() for why this is considered bad.
2316 	 */
2317 	if ((tdzp->z_phys->zp_flags & ZFS_XATTR) !=
2318 	    (sdzp->z_phys->zp_flags & ZFS_XATTR)) {
2319 		ZFS_EXIT(zfsvfs);
2320 		return (EINVAL);
2321 	}
2322 
2323 	/*
2324 	 * Lock source and target directory entries.  To prevent deadlock,
2325 	 * a lock ordering must be defined.  We lock the directory with
2326 	 * the smallest object id first, or if it's a tie, the one with
2327 	 * the lexically first name.
2328 	 */
2329 	if (sdzp->z_id < tdzp->z_id) {
2330 		cmp = -1;
2331 	} else if (sdzp->z_id > tdzp->z_id) {
2332 		cmp = 1;
2333 	} else {
2334 		cmp = strcmp(snm, tnm);
2335 		if (cmp == 0) {
2336 			/*
2337 			 * POSIX: "If the old argument and the new argument
2338 			 * both refer to links to the same existing file,
2339 			 * the rename() function shall return successfully
2340 			 * and perform no other action."
2341 			 */
2342 			ZFS_EXIT(zfsvfs);
2343 			return (0);
2344 		}
2345 	}
2346 	if (cmp < 0) {
2347 		serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS);
2348 		terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0);
2349 	} else {
2350 		terr = zfs_dirent_lock(&tdl, tdzp, tnm, &tzp, 0);
2351 		serr = zfs_dirent_lock(&sdl, sdzp, snm, &szp, ZEXISTS);
2352 	}
2353 
2354 	if (serr) {
2355 		/*
2356 		 * Source entry invalid or not there.
2357 		 */
2358 		if (!terr) {
2359 			zfs_dirent_unlock(tdl);
2360 			if (tzp)
2361 				VN_RELE(ZTOV(tzp));
2362 		}
2363 		if (strcmp(snm, "..") == 0)
2364 			serr = EINVAL;
2365 		ZFS_EXIT(zfsvfs);
2366 		return (serr);
2367 	}
2368 	if (terr) {
2369 		zfs_dirent_unlock(sdl);
2370 		VN_RELE(ZTOV(szp));
2371 		if (strcmp(tnm, "..") == 0)
2372 			terr = EINVAL;
2373 		ZFS_EXIT(zfsvfs);
2374 		return (terr);
2375 	}
2376 
2377 	/*
2378 	 * Must have write access at the source to remove the old entry
2379 	 * and write access at the target to create the new entry.
2380 	 * Note that if target and source are the same, this can be
2381 	 * done in a single check.
2382 	 */
2383 
2384 	if (error = zfs_zaccess_rename(sdzp, szp, tdzp, tzp, cr))
2385 		goto out;
2386 
2387 	if (ZTOV(szp)->v_type == VDIR) {
2388 		/*
2389 		 * Check to make sure rename is valid.
2390 		 * Can't do a move like this: /usr/a/b to /usr/a/b/c/d
2391 		 */
2392 		if (error = zfs_rename_lock(szp, tdzp, sdzp, &zl))
2393 			goto out;
2394 	}
2395 
2396 	/*
2397 	 * Does target exist?
2398 	 */
2399 	if (tzp) {
2400 		/*
2401 		 * Source and target must be the same type.
2402 		 */
2403 		if (ZTOV(szp)->v_type == VDIR) {
2404 			if (ZTOV(tzp)->v_type != VDIR) {
2405 				error = ENOTDIR;
2406 				goto out;
2407 			}
2408 		} else {
2409 			if (ZTOV(tzp)->v_type == VDIR) {
2410 				error = EISDIR;
2411 				goto out;
2412 			}
2413 		}
2414 		/*
2415 		 * POSIX dictates that when the source and target
2416 		 * entries refer to the same file object, rename
2417 		 * must do nothing and exit without error.
2418 		 */
2419 		if (szp->z_id == tzp->z_id) {
2420 			error = 0;
2421 			goto out;
2422 		}
2423 	}
2424 
2425 	vnevent_rename_src(ZTOV(szp));
2426 	if (tzp)
2427 		vnevent_rename_dest(ZTOV(tzp));
2428 
2429 	tx = dmu_tx_create(zfsvfs->z_os);
2430 	dmu_tx_hold_bonus(tx, szp->z_id);	/* nlink changes */
2431 	dmu_tx_hold_bonus(tx, sdzp->z_id);	/* nlink changes */
2432 	dmu_tx_hold_zap(tx, sdzp->z_id, FALSE, snm);
2433 	dmu_tx_hold_zap(tx, tdzp->z_id, TRUE, tnm);
2434 	if (sdzp != tdzp)
2435 		dmu_tx_hold_bonus(tx, tdzp->z_id);	/* nlink changes */
2436 	if (tzp)
2437 		dmu_tx_hold_bonus(tx, tzp->z_id);	/* parent changes */
2438 	dmu_tx_hold_zap(tx, zfsvfs->z_unlinkedobj, FALSE, NULL);
2439 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
2440 	if (error) {
2441 		if (zl != NULL)
2442 			zfs_rename_unlock(&zl);
2443 		zfs_dirent_unlock(sdl);
2444 		zfs_dirent_unlock(tdl);
2445 		VN_RELE(ZTOV(szp));
2446 		if (tzp)
2447 			VN_RELE(ZTOV(tzp));
2448 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2449 			dmu_tx_wait(tx);
2450 			dmu_tx_abort(tx);
2451 			goto top;
2452 		}
2453 		dmu_tx_abort(tx);
2454 		ZFS_EXIT(zfsvfs);
2455 		return (error);
2456 	}
2457 
2458 	if (tzp)	/* Attempt to remove the existing target */
2459 		error = zfs_link_destroy(tdl, tzp, tx, 0, NULL);
2460 
2461 	if (error == 0) {
2462 		error = zfs_link_create(tdl, szp, tx, ZRENAMING);
2463 		if (error == 0) {
2464 			error = zfs_link_destroy(sdl, szp, tx, ZRENAMING, NULL);
2465 			ASSERT(error == 0);
2466 			zfs_log_rename(zilog, tx, TX_RENAME, sdzp,
2467 			    sdl->dl_name, tdzp, tdl->dl_name, szp);
2468 		}
2469 	}
2470 
2471 	dmu_tx_commit(tx);
2472 out:
2473 	if (zl != NULL)
2474 		zfs_rename_unlock(&zl);
2475 
2476 	zfs_dirent_unlock(sdl);
2477 	zfs_dirent_unlock(tdl);
2478 
2479 	VN_RELE(ZTOV(szp));
2480 	if (tzp)
2481 		VN_RELE(ZTOV(tzp));
2482 
2483 	ZFS_EXIT(zfsvfs);
2484 	return (error);
2485 }
2486 
2487 /*
2488  * Insert the indicated symbolic reference entry into the directory.
2489  *
2490  *	IN:	dvp	- Directory to contain new symbolic link.
2491  *		link	- Name for new symlink entry.
2492  *		vap	- Attributes of new entry.
2493  *		target	- Target path of new symlink.
2494  *		cr	- credentials of caller.
2495  *
2496  *	RETURN:	0 if success
2497  *		error code if failure
2498  *
2499  * Timestamps:
2500  *	dvp - ctime|mtime updated
2501  */
2502 static int
2503 zfs_symlink(vnode_t *dvp, char *name, vattr_t *vap, char *link, cred_t *cr)
2504 {
2505 	znode_t		*zp, *dzp = VTOZ(dvp);
2506 	zfs_dirlock_t	*dl;
2507 	dmu_tx_t	*tx;
2508 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
2509 	zilog_t		*zilog = zfsvfs->z_log;
2510 	uint64_t	zoid;
2511 	int		len = strlen(link);
2512 	int		error;
2513 
2514 	ASSERT(vap->va_type == VLNK);
2515 
2516 	ZFS_ENTER(zfsvfs);
2517 top:
2518 	if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) {
2519 		ZFS_EXIT(zfsvfs);
2520 		return (error);
2521 	}
2522 
2523 	if (len > MAXPATHLEN) {
2524 		ZFS_EXIT(zfsvfs);
2525 		return (ENAMETOOLONG);
2526 	}
2527 
2528 	/*
2529 	 * Attempt to lock directory; fail if entry already exists.
2530 	 */
2531 	if (error = zfs_dirent_lock(&dl, dzp, name, &zp, ZNEW)) {
2532 		ZFS_EXIT(zfsvfs);
2533 		return (error);
2534 	}
2535 
2536 	tx = dmu_tx_create(zfsvfs->z_os);
2537 	dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, MAX(1, len));
2538 	dmu_tx_hold_bonus(tx, dzp->z_id);
2539 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
2540 	if (dzp->z_phys->zp_flags & ZFS_INHERIT_ACE)
2541 		dmu_tx_hold_write(tx, DMU_NEW_OBJECT, 0, SPA_MAXBLOCKSIZE);
2542 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
2543 	if (error) {
2544 		zfs_dirent_unlock(dl);
2545 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2546 			dmu_tx_wait(tx);
2547 			dmu_tx_abort(tx);
2548 			goto top;
2549 		}
2550 		dmu_tx_abort(tx);
2551 		ZFS_EXIT(zfsvfs);
2552 		return (error);
2553 	}
2554 
2555 	dmu_buf_will_dirty(dzp->z_dbuf, tx);
2556 
2557 	/*
2558 	 * Create a new object for the symlink.
2559 	 * Put the link content into bonus buffer if it will fit;
2560 	 * otherwise, store it just like any other file data.
2561 	 */
2562 	zoid = 0;
2563 	if (sizeof (znode_phys_t) + len <= dmu_bonus_max()) {
2564 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, len);
2565 		if (len != 0)
2566 			bcopy(link, zp->z_phys + 1, len);
2567 	} else {
2568 		dmu_buf_t *dbp;
2569 
2570 		zfs_mknode(dzp, vap, &zoid, tx, cr, 0, &zp, 0);
2571 
2572 		/*
2573 		 * Nothing can access the znode yet so no locking needed
2574 		 * for growing the znode's blocksize.
2575 		 */
2576 		zfs_grow_blocksize(zp, len, tx);
2577 
2578 		VERIFY(0 == dmu_buf_hold(zfsvfs->z_os, zoid, 0, FTAG, &dbp));
2579 		dmu_buf_will_dirty(dbp, tx);
2580 
2581 		ASSERT3U(len, <=, dbp->db_size);
2582 		bcopy(link, dbp->db_data, len);
2583 		dmu_buf_rele(dbp, FTAG);
2584 	}
2585 	zp->z_phys->zp_size = len;
2586 
2587 	/*
2588 	 * Insert the new object into the directory.
2589 	 */
2590 	(void) zfs_link_create(dl, zp, tx, ZNEW);
2591 out:
2592 	if (error == 0)
2593 		zfs_log_symlink(zilog, tx, TX_SYMLINK, dzp, zp, name, link);
2594 
2595 	dmu_tx_commit(tx);
2596 
2597 	zfs_dirent_unlock(dl);
2598 
2599 	VN_RELE(ZTOV(zp));
2600 
2601 	ZFS_EXIT(zfsvfs);
2602 	return (error);
2603 }
2604 
2605 /*
2606  * Return, in the buffer contained in the provided uio structure,
2607  * the symbolic path referred to by vp.
2608  *
2609  *	IN:	vp	- vnode of symbolic link.
2610  *		uoip	- structure to contain the link path.
2611  *		cr	- credentials of caller.
2612  *
2613  *	OUT:	uio	- structure to contain the link path.
2614  *
2615  *	RETURN:	0 if success
2616  *		error code if failure
2617  *
2618  * Timestamps:
2619  *	vp - atime updated
2620  */
2621 /* ARGSUSED */
2622 static int
2623 zfs_readlink(vnode_t *vp, uio_t *uio, cred_t *cr)
2624 {
2625 	znode_t		*zp = VTOZ(vp);
2626 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
2627 	size_t		bufsz;
2628 	int		error;
2629 
2630 	ZFS_ENTER(zfsvfs);
2631 
2632 	bufsz = (size_t)zp->z_phys->zp_size;
2633 	if (bufsz + sizeof (znode_phys_t) <= zp->z_dbuf->db_size) {
2634 		error = uiomove(zp->z_phys + 1,
2635 		    MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
2636 	} else {
2637 		dmu_buf_t *dbp;
2638 		error = dmu_buf_hold(zfsvfs->z_os, zp->z_id, 0, FTAG, &dbp);
2639 		if (error) {
2640 			ZFS_EXIT(zfsvfs);
2641 			return (error);
2642 		}
2643 		error = uiomove(dbp->db_data,
2644 		    MIN((size_t)bufsz, uio->uio_resid), UIO_READ, uio);
2645 		dmu_buf_rele(dbp, FTAG);
2646 	}
2647 
2648 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
2649 	ZFS_EXIT(zfsvfs);
2650 	return (error);
2651 }
2652 
2653 /*
2654  * Insert a new entry into directory tdvp referencing svp.
2655  *
2656  *	IN:	tdvp	- Directory to contain new entry.
2657  *		svp	- vnode of new entry.
2658  *		name	- name of new entry.
2659  *		cr	- credentials of caller.
2660  *
2661  *	RETURN:	0 if success
2662  *		error code if failure
2663  *
2664  * Timestamps:
2665  *	tdvp - ctime|mtime updated
2666  *	 svp - ctime updated
2667  */
2668 /* ARGSUSED */
2669 static int
2670 zfs_link(vnode_t *tdvp, vnode_t *svp, char *name, cred_t *cr)
2671 {
2672 	znode_t		*dzp = VTOZ(tdvp);
2673 	znode_t		*tzp, *szp;
2674 	zfsvfs_t	*zfsvfs = dzp->z_zfsvfs;
2675 	zilog_t		*zilog = zfsvfs->z_log;
2676 	zfs_dirlock_t	*dl;
2677 	dmu_tx_t	*tx;
2678 	vnode_t		*realvp;
2679 	int		error;
2680 
2681 	ASSERT(tdvp->v_type == VDIR);
2682 
2683 	ZFS_ENTER(zfsvfs);
2684 
2685 	if (VOP_REALVP(svp, &realvp) == 0)
2686 		svp = realvp;
2687 
2688 	if (svp->v_vfsp != tdvp->v_vfsp) {
2689 		ZFS_EXIT(zfsvfs);
2690 		return (EXDEV);
2691 	}
2692 
2693 	szp = VTOZ(svp);
2694 top:
2695 	/*
2696 	 * We do not support links between attributes and non-attributes
2697 	 * because of the potential security risk of creating links
2698 	 * into "normal" file space in order to circumvent restrictions
2699 	 * imposed in attribute space.
2700 	 */
2701 	if ((szp->z_phys->zp_flags & ZFS_XATTR) !=
2702 	    (dzp->z_phys->zp_flags & ZFS_XATTR)) {
2703 		ZFS_EXIT(zfsvfs);
2704 		return (EINVAL);
2705 	}
2706 
2707 	/*
2708 	 * POSIX dictates that we return EPERM here.
2709 	 * Better choices include ENOTSUP or EISDIR.
2710 	 */
2711 	if (svp->v_type == VDIR) {
2712 		ZFS_EXIT(zfsvfs);
2713 		return (EPERM);
2714 	}
2715 
2716 	if ((uid_t)szp->z_phys->zp_uid != crgetuid(cr) &&
2717 	    secpolicy_basic_link(cr) != 0) {
2718 		ZFS_EXIT(zfsvfs);
2719 		return (EPERM);
2720 	}
2721 
2722 	if (error = zfs_zaccess(dzp, ACE_ADD_FILE, cr)) {
2723 		ZFS_EXIT(zfsvfs);
2724 		return (error);
2725 	}
2726 
2727 	/*
2728 	 * Attempt to lock directory; fail if entry already exists.
2729 	 */
2730 	if (error = zfs_dirent_lock(&dl, dzp, name, &tzp, ZNEW)) {
2731 		ZFS_EXIT(zfsvfs);
2732 		return (error);
2733 	}
2734 
2735 	tx = dmu_tx_create(zfsvfs->z_os);
2736 	dmu_tx_hold_bonus(tx, szp->z_id);
2737 	dmu_tx_hold_zap(tx, dzp->z_id, TRUE, name);
2738 	error = dmu_tx_assign(tx, zfsvfs->z_assign);
2739 	if (error) {
2740 		zfs_dirent_unlock(dl);
2741 		if (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2742 			dmu_tx_wait(tx);
2743 			dmu_tx_abort(tx);
2744 			goto top;
2745 		}
2746 		dmu_tx_abort(tx);
2747 		ZFS_EXIT(zfsvfs);
2748 		return (error);
2749 	}
2750 
2751 	error = zfs_link_create(dl, szp, tx, 0);
2752 
2753 	if (error == 0)
2754 		zfs_log_link(zilog, tx, TX_LINK, dzp, szp, name);
2755 
2756 	dmu_tx_commit(tx);
2757 
2758 	zfs_dirent_unlock(dl);
2759 
2760 	ZFS_EXIT(zfsvfs);
2761 	return (error);
2762 }
2763 
2764 /*
2765  * zfs_null_putapage() is used when the file system has been force
2766  * unmounted. It just drops the pages.
2767  */
2768 /* ARGSUSED */
2769 static int
2770 zfs_null_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp,
2771 		size_t *lenp, int flags, cred_t *cr)
2772 {
2773 	pvn_write_done(pp, B_INVAL|B_FORCE|B_ERROR);
2774 	return (0);
2775 }
2776 
2777 /*
2778  * Push a page out to disk, klustering if possible.
2779  *
2780  *	IN:	vp	- file to push page to.
2781  *		pp	- page to push.
2782  *		flags	- additional flags.
2783  *		cr	- credentials of caller.
2784  *
2785  *	OUT:	offp	- start of range pushed.
2786  *		lenp	- len of range pushed.
2787  *
2788  *	RETURN:	0 if success
2789  *		error code if failure
2790  *
2791  * NOTE: callers must have locked the page to be pushed.  On
2792  * exit, the page (and all other pages in the kluster) must be
2793  * unlocked.
2794  */
2795 /* ARGSUSED */
2796 static int
2797 zfs_putapage(vnode_t *vp, page_t *pp, u_offset_t *offp,
2798 		size_t *lenp, int flags, cred_t *cr)
2799 {
2800 	znode_t		*zp = VTOZ(vp);
2801 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
2802 	zilog_t		*zilog = zfsvfs->z_log;
2803 	dmu_tx_t	*tx;
2804 	rl_t		*rl;
2805 	u_offset_t	off, koff;
2806 	size_t		len, klen;
2807 	int		err;
2808 
2809 	off = pp->p_offset;
2810 	len = PAGESIZE;
2811 	/*
2812 	 * If our blocksize is bigger than the page size, try to kluster
2813 	 * muiltiple pages so that we write a full block (thus avoiding
2814 	 * a read-modify-write).
2815 	 */
2816 	if (zp->z_blksz > PAGESIZE) {
2817 		uint64_t filesz = zp->z_phys->zp_size;
2818 
2819 		if (!ISP2(zp->z_blksz)) {
2820 			/* Only one block in the file. */
2821 			klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE);
2822 			koff = 0;
2823 		} else {
2824 			klen = zp->z_blksz;
2825 			koff = P2ALIGN(off, (u_offset_t)klen);
2826 		}
2827 		ASSERT(koff <= filesz);
2828 		if (koff + klen > filesz)
2829 			klen = P2ROUNDUP(filesz - koff, (uint64_t)PAGESIZE);
2830 		pp = pvn_write_kluster(vp, pp, &off, &len, koff, klen, flags);
2831 	}
2832 	ASSERT3U(btop(len), ==, btopr(len));
2833 top:
2834 	rl = zfs_range_lock(zp, off, len, RL_WRITER);
2835 	/*
2836 	 * Can't push pages past end-of-file.
2837 	 */
2838 	if (off >= zp->z_phys->zp_size) {
2839 		/* discard all pages */
2840 		flags |= B_INVAL;
2841 		err = 0;
2842 		goto out;
2843 	} else if (off + len > zp->z_phys->zp_size) {
2844 		int npages = btopr(zp->z_phys->zp_size - off);
2845 		page_t *trunc;
2846 
2847 		page_list_break(&pp, &trunc, npages);
2848 		/* discard pages past end of file */
2849 		if (trunc)
2850 			pvn_write_done(trunc, B_INVAL | flags);
2851 		len = zp->z_phys->zp_size - off;
2852 	}
2853 
2854 	tx = dmu_tx_create(zfsvfs->z_os);
2855 	dmu_tx_hold_write(tx, zp->z_id, off, len);
2856 	dmu_tx_hold_bonus(tx, zp->z_id);
2857 	err = dmu_tx_assign(tx, zfsvfs->z_assign);
2858 	if (err != 0) {
2859 		if (err == ERESTART && zfsvfs->z_assign == TXG_NOWAIT) {
2860 			zfs_range_unlock(rl);
2861 			dmu_tx_wait(tx);
2862 			dmu_tx_abort(tx);
2863 			err = 0;
2864 			goto top;
2865 		}
2866 		dmu_tx_abort(tx);
2867 		goto out;
2868 	}
2869 
2870 	if (zp->z_blksz <= PAGESIZE) {
2871 		caddr_t va = ppmapin(pp, PROT_READ, (caddr_t)-1);
2872 		ASSERT3U(len, <=, PAGESIZE);
2873 		dmu_write(zfsvfs->z_os, zp->z_id, off, len, va, tx);
2874 		ppmapout(va);
2875 	} else {
2876 		err = dmu_write_pages(zfsvfs->z_os, zp->z_id, off, len, pp, tx);
2877 	}
2878 
2879 	if (err == 0) {
2880 		zfs_time_stamper(zp, CONTENT_MODIFIED, tx);
2881 		zfs_log_write(zilog, tx, TX_WRITE, zp, off, len, 0);
2882 		dmu_tx_commit(tx);
2883 	}
2884 
2885 out:
2886 	zfs_range_unlock(rl);
2887 	pvn_write_done(pp, (err ? B_ERROR : 0) | B_WRITE | flags);
2888 	if (offp)
2889 		*offp = off;
2890 	if (lenp)
2891 		*lenp = len;
2892 
2893 	return (err);
2894 }
2895 
2896 /*
2897  * Copy the portion of the file indicated from pages into the file.
2898  * The pages are stored in a page list attached to the files vnode.
2899  *
2900  *	IN:	vp	- vnode of file to push page data to.
2901  *		off	- position in file to put data.
2902  *		len	- amount of data to write.
2903  *		flags	- flags to control the operation.
2904  *		cr	- credentials of caller.
2905  *
2906  *	RETURN:	0 if success
2907  *		error code if failure
2908  *
2909  * Timestamps:
2910  *	vp - ctime|mtime updated
2911  */
2912 static int
2913 zfs_putpage(vnode_t *vp, offset_t off, size_t len, int flags, cred_t *cr)
2914 {
2915 	znode_t		*zp = VTOZ(vp);
2916 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
2917 	page_t		*pp;
2918 	size_t		io_len;
2919 	u_offset_t	io_off;
2920 	uint64_t	filesz;
2921 	int		error = 0;
2922 
2923 	ZFS_ENTER(zfsvfs);
2924 
2925 	ASSERT(zp->z_dbuf_held && zp->z_phys);
2926 
2927 	if (len == 0) {
2928 		/*
2929 		 * Search the entire vp list for pages >= off.
2930 		 */
2931 		error = pvn_vplist_dirty(vp, (u_offset_t)off, zfs_putapage,
2932 		    flags, cr);
2933 		goto out;
2934 	}
2935 
2936 	filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */
2937 	if (off > filesz) {
2938 		/* past end of file */
2939 		ZFS_EXIT(zfsvfs);
2940 		return (0);
2941 	}
2942 
2943 	len = MIN(len, filesz - off);
2944 
2945 	for (io_off = off; io_off < off + len; io_off += io_len) {
2946 		if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) {
2947 			pp = page_lookup(vp, io_off,
2948 				(flags & (B_INVAL | B_FREE)) ?
2949 					SE_EXCL : SE_SHARED);
2950 		} else {
2951 			pp = page_lookup_nowait(vp, io_off,
2952 				(flags & B_FREE) ? SE_EXCL : SE_SHARED);
2953 		}
2954 
2955 		if (pp != NULL && pvn_getdirty(pp, flags)) {
2956 			int err;
2957 
2958 			/*
2959 			 * Found a dirty page to push
2960 			 */
2961 			err = zfs_putapage(vp, pp, &io_off, &io_len, flags, cr);
2962 			if (err)
2963 				error = err;
2964 		} else {
2965 			io_len = PAGESIZE;
2966 		}
2967 	}
2968 out:
2969 	if ((flags & B_ASYNC) == 0)
2970 		zil_commit(zfsvfs->z_log, UINT64_MAX, zp->z_id);
2971 	ZFS_EXIT(zfsvfs);
2972 	return (error);
2973 }
2974 
2975 void
2976 zfs_inactive(vnode_t *vp, cred_t *cr)
2977 {
2978 	znode_t	*zp = VTOZ(vp);
2979 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
2980 	int error;
2981 
2982 	rw_enter(&zfsvfs->z_um_lock, RW_READER);
2983 	if (zfsvfs->z_unmounted2) {
2984 		ASSERT(zp->z_dbuf_held == 0);
2985 
2986 		if (vn_has_cached_data(vp)) {
2987 			(void) pvn_vplist_dirty(vp, 0, zfs_null_putapage,
2988 			    B_INVAL, cr);
2989 		}
2990 
2991 		mutex_enter(&zp->z_lock);
2992 		vp->v_count = 0; /* count arrives as 1 */
2993 		if (zp->z_dbuf == NULL) {
2994 			mutex_exit(&zp->z_lock);
2995 			zfs_znode_free(zp);
2996 		} else {
2997 			mutex_exit(&zp->z_lock);
2998 		}
2999 		rw_exit(&zfsvfs->z_um_lock);
3000 		VFS_RELE(zfsvfs->z_vfs);
3001 		return;
3002 	}
3003 
3004 	/*
3005 	 * Attempt to push any data in the page cache.  If this fails
3006 	 * we will get kicked out later in zfs_zinactive().
3007 	 */
3008 	if (vn_has_cached_data(vp)) {
3009 		(void) pvn_vplist_dirty(vp, 0, zfs_putapage, B_INVAL|B_ASYNC,
3010 		    cr);
3011 	}
3012 
3013 	if (zp->z_atime_dirty && zp->z_unlinked == 0) {
3014 		dmu_tx_t *tx = dmu_tx_create(zfsvfs->z_os);
3015 
3016 		dmu_tx_hold_bonus(tx, zp->z_id);
3017 		error = dmu_tx_assign(tx, TXG_WAIT);
3018 		if (error) {
3019 			dmu_tx_abort(tx);
3020 		} else {
3021 			dmu_buf_will_dirty(zp->z_dbuf, tx);
3022 			mutex_enter(&zp->z_lock);
3023 			zp->z_atime_dirty = 0;
3024 			mutex_exit(&zp->z_lock);
3025 			dmu_tx_commit(tx);
3026 		}
3027 	}
3028 
3029 	zfs_zinactive(zp);
3030 	rw_exit(&zfsvfs->z_um_lock);
3031 }
3032 
3033 /*
3034  * Bounds-check the seek operation.
3035  *
3036  *	IN:	vp	- vnode seeking within
3037  *		ooff	- old file offset
3038  *		noffp	- pointer to new file offset
3039  *
3040  *	RETURN:	0 if success
3041  *		EINVAL if new offset invalid
3042  */
3043 /* ARGSUSED */
3044 static int
3045 zfs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp)
3046 {
3047 	if (vp->v_type == VDIR)
3048 		return (0);
3049 	return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
3050 }
3051 
3052 /*
3053  * Pre-filter the generic locking function to trap attempts to place
3054  * a mandatory lock on a memory mapped file.
3055  */
3056 static int
3057 zfs_frlock(vnode_t *vp, int cmd, flock64_t *bfp, int flag, offset_t offset,
3058     flk_callback_t *flk_cbp, cred_t *cr)
3059 {
3060 	znode_t *zp = VTOZ(vp);
3061 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3062 	int error;
3063 
3064 	ZFS_ENTER(zfsvfs);
3065 
3066 	/*
3067 	 * We are following the UFS semantics with respect to mapcnt
3068 	 * here: If we see that the file is mapped already, then we will
3069 	 * return an error, but we don't worry about races between this
3070 	 * function and zfs_map().
3071 	 */
3072 	if (zp->z_mapcnt > 0 && MANDMODE((mode_t)zp->z_phys->zp_mode)) {
3073 		ZFS_EXIT(zfsvfs);
3074 		return (EAGAIN);
3075 	}
3076 	error = fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr);
3077 	ZFS_EXIT(zfsvfs);
3078 	return (error);
3079 }
3080 
3081 /*
3082  * If we can't find a page in the cache, we will create a new page
3083  * and fill it with file data.  For efficiency, we may try to fill
3084  * multiple pages at once (klustering).
3085  */
3086 static int
3087 zfs_fillpage(vnode_t *vp, u_offset_t off, struct seg *seg,
3088     caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw)
3089 {
3090 	znode_t *zp = VTOZ(vp);
3091 	page_t *pp, *cur_pp;
3092 	objset_t *os = zp->z_zfsvfs->z_os;
3093 	caddr_t va;
3094 	u_offset_t io_off, total;
3095 	uint64_t oid = zp->z_id;
3096 	size_t io_len;
3097 	uint64_t filesz;
3098 	int err;
3099 
3100 	/*
3101 	 * If we are only asking for a single page don't bother klustering.
3102 	 */
3103 	filesz = zp->z_phys->zp_size; /* get consistent copy of zp_size */
3104 	if (off >= filesz)
3105 		return (EFAULT);
3106 	if (plsz == PAGESIZE || zp->z_blksz <= PAGESIZE) {
3107 		io_off = off;
3108 		io_len = PAGESIZE;
3109 		pp = page_create_va(vp, io_off, io_len, PG_WAIT, seg, addr);
3110 	} else {
3111 		/*
3112 		 * Try to fill a kluster of pages (a blocks worth).
3113 		 */
3114 		size_t klen;
3115 		u_offset_t koff;
3116 
3117 		if (!ISP2(zp->z_blksz)) {
3118 			/* Only one block in the file. */
3119 			klen = P2ROUNDUP((ulong_t)zp->z_blksz, PAGESIZE);
3120 			koff = 0;
3121 		} else {
3122 			/*
3123 			 * It would be ideal to align our offset to the
3124 			 * blocksize but doing so has resulted in some
3125 			 * strange application crashes. For now, we
3126 			 * leave the offset as is and only adjust the
3127 			 * length if we are off the end of the file.
3128 			 */
3129 			koff = off;
3130 			klen = plsz;
3131 		}
3132 		ASSERT(koff <= filesz);
3133 		if (koff + klen > filesz)
3134 			klen = P2ROUNDUP(filesz, (uint64_t)PAGESIZE) - koff;
3135 		ASSERT3U(off, >=, koff);
3136 		ASSERT3U(off, <, koff + klen);
3137 		pp = pvn_read_kluster(vp, off, seg, addr, &io_off,
3138 			    &io_len, koff, klen, 0);
3139 	}
3140 	if (pp == NULL) {
3141 		/*
3142 		 * Some other thread entered the page before us.
3143 		 * Return to zfs_getpage to retry the lookup.
3144 		 */
3145 		*pl = NULL;
3146 		return (0);
3147 	}
3148 
3149 	/*
3150 	 * Fill the pages in the kluster.
3151 	 */
3152 	cur_pp = pp;
3153 	for (total = io_off + io_len; io_off < total; io_off += PAGESIZE) {
3154 		ASSERT3U(io_off, ==, cur_pp->p_offset);
3155 		va = ppmapin(cur_pp, PROT_READ | PROT_WRITE, (caddr_t)-1);
3156 		err = dmu_read(os, oid, io_off, PAGESIZE, va);
3157 		ppmapout(va);
3158 		if (err) {
3159 			/* On error, toss the entire kluster */
3160 			pvn_read_done(pp, B_ERROR);
3161 			return (err);
3162 		}
3163 		cur_pp = cur_pp->p_next;
3164 	}
3165 out:
3166 	/*
3167 	 * Fill in the page list array from the kluster.  If
3168 	 * there are too many pages in the kluster, return
3169 	 * as many pages as possible starting from the desired
3170 	 * offset `off'.
3171 	 * NOTE: the page list will always be null terminated.
3172 	 */
3173 	pvn_plist_init(pp, pl, plsz, off, io_len, rw);
3174 
3175 	return (0);
3176 }
3177 
3178 /*
3179  * Return pointers to the pages for the file region [off, off + len]
3180  * in the pl array.  If plsz is greater than len, this function may
3181  * also return page pointers from before or after the specified
3182  * region (i.e. some region [off', off' + plsz]).  These additional
3183  * pages are only returned if they are already in the cache, or were
3184  * created as part of a klustered read.
3185  *
3186  *	IN:	vp	- vnode of file to get data from.
3187  *		off	- position in file to get data from.
3188  *		len	- amount of data to retrieve.
3189  *		plsz	- length of provided page list.
3190  *		seg	- segment to obtain pages for.
3191  *		addr	- virtual address of fault.
3192  *		rw	- mode of created pages.
3193  *		cr	- credentials of caller.
3194  *
3195  *	OUT:	protp	- protection mode of created pages.
3196  *		pl	- list of pages created.
3197  *
3198  *	RETURN:	0 if success
3199  *		error code if failure
3200  *
3201  * Timestamps:
3202  *	vp - atime updated
3203  */
3204 /* ARGSUSED */
3205 static int
3206 zfs_getpage(vnode_t *vp, offset_t off, size_t len, uint_t *protp,
3207 	page_t *pl[], size_t plsz, struct seg *seg, caddr_t addr,
3208 	enum seg_rw rw, cred_t *cr)
3209 {
3210 	znode_t		*zp = VTOZ(vp);
3211 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3212 	page_t		*pp, **pl0 = pl;
3213 	int		need_unlock = 0, err = 0;
3214 	offset_t	orig_off;
3215 
3216 	ZFS_ENTER(zfsvfs);
3217 
3218 	if (protp)
3219 		*protp = PROT_ALL;
3220 
3221 	ASSERT(zp->z_dbuf_held && zp->z_phys);
3222 
3223 	/* no faultahead (for now) */
3224 	if (pl == NULL) {
3225 		ZFS_EXIT(zfsvfs);
3226 		return (0);
3227 	}
3228 
3229 	/* can't fault past EOF */
3230 	if (off >= zp->z_phys->zp_size) {
3231 		ZFS_EXIT(zfsvfs);
3232 		return (EFAULT);
3233 	}
3234 	orig_off = off;
3235 
3236 	/*
3237 	 * If we already own the lock, then we must be page faulting
3238 	 * in the middle of a write to this file (i.e., we are writing
3239 	 * to this file using data from a mapped region of the file).
3240 	 */
3241 	if (rw_owner(&zp->z_map_lock) != curthread) {
3242 		rw_enter(&zp->z_map_lock, RW_WRITER);
3243 		need_unlock = TRUE;
3244 	}
3245 
3246 	/*
3247 	 * Loop through the requested range [off, off + len] looking
3248 	 * for pages.  If we don't find a page, we will need to create
3249 	 * a new page and fill it with data from the file.
3250 	 */
3251 	while (len > 0) {
3252 		if (plsz < PAGESIZE)
3253 			break;
3254 		if (pp = page_lookup(vp, off, SE_SHARED)) {
3255 			*pl++ = pp;
3256 			off += PAGESIZE;
3257 			addr += PAGESIZE;
3258 			len -= PAGESIZE;
3259 			plsz -= PAGESIZE;
3260 		} else {
3261 			err = zfs_fillpage(vp, off, seg, addr, pl, plsz, rw);
3262 			if (err)
3263 				goto out;
3264 			/*
3265 			 * klustering may have changed our region
3266 			 * to be block aligned.
3267 			 */
3268 			if (((pp = *pl) != 0) && (off != pp->p_offset)) {
3269 				int delta = off - pp->p_offset;
3270 				len += delta;
3271 				off -= delta;
3272 				addr -= delta;
3273 			}
3274 			while (*pl) {
3275 				pl++;
3276 				off += PAGESIZE;
3277 				addr += PAGESIZE;
3278 				plsz -= PAGESIZE;
3279 				if (len > PAGESIZE)
3280 					len -= PAGESIZE;
3281 				else
3282 					len = 0;
3283 			}
3284 		}
3285 	}
3286 
3287 	/*
3288 	 * Fill out the page array with any pages already in the cache.
3289 	 */
3290 	while (plsz > 0) {
3291 		pp = page_lookup_nowait(vp, off, SE_SHARED);
3292 		if (pp == NULL)
3293 			break;
3294 		*pl++ = pp;
3295 		off += PAGESIZE;
3296 		plsz -= PAGESIZE;
3297 	}
3298 
3299 	ZFS_ACCESSTIME_STAMP(zfsvfs, zp);
3300 out:
3301 	/*
3302 	 * We can't grab the range lock for the page as reader which would
3303 	 * stop truncation as this leads to deadlock. So we need to recheck
3304 	 * the file size.
3305 	 */
3306 	if (orig_off >= zp->z_phys->zp_size)
3307 		err = EFAULT;
3308 	if (err) {
3309 		/*
3310 		 * Release any pages we have previously locked.
3311 		 */
3312 		while (pl > pl0)
3313 			page_unlock(*--pl);
3314 	}
3315 
3316 	*pl = NULL;
3317 
3318 	if (need_unlock)
3319 		rw_exit(&zp->z_map_lock);
3320 
3321 	ZFS_EXIT(zfsvfs);
3322 	return (err);
3323 }
3324 
3325 /*
3326  * Request a memory map for a section of a file.  This code interacts
3327  * with common code and the VM system as follows:
3328  *
3329  *	common code calls mmap(), which ends up in smmap_common()
3330  *
3331  *	this calls VOP_MAP(), which takes you into (say) zfs
3332  *
3333  *	zfs_map() calls as_map(), passing segvn_create() as the callback
3334  *
3335  *	segvn_create() creates the new segment and calls VOP_ADDMAP()
3336  *
3337  *	zfs_addmap() updates z_mapcnt
3338  */
3339 static int
3340 zfs_map(vnode_t *vp, offset_t off, struct as *as, caddr_t *addrp,
3341     size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr)
3342 {
3343 	znode_t *zp = VTOZ(vp);
3344 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3345 	segvn_crargs_t	vn_a;
3346 	int		error;
3347 
3348 	ZFS_ENTER(zfsvfs);
3349 
3350 	if (vp->v_flag & VNOMAP) {
3351 		ZFS_EXIT(zfsvfs);
3352 		return (ENOSYS);
3353 	}
3354 
3355 	if (off < 0 || len > MAXOFFSET_T - off) {
3356 		ZFS_EXIT(zfsvfs);
3357 		return (ENXIO);
3358 	}
3359 
3360 	if (vp->v_type != VREG) {
3361 		ZFS_EXIT(zfsvfs);
3362 		return (ENODEV);
3363 	}
3364 
3365 	/*
3366 	 * If file is locked, disallow mapping.
3367 	 */
3368 	if (MANDMODE((mode_t)zp->z_phys->zp_mode) && vn_has_flocks(vp)) {
3369 		ZFS_EXIT(zfsvfs);
3370 		return (EAGAIN);
3371 	}
3372 
3373 	as_rangelock(as);
3374 	if ((flags & MAP_FIXED) == 0) {
3375 		map_addr(addrp, len, off, 1, flags);
3376 		if (*addrp == NULL) {
3377 			as_rangeunlock(as);
3378 			ZFS_EXIT(zfsvfs);
3379 			return (ENOMEM);
3380 		}
3381 	} else {
3382 		/*
3383 		 * User specified address - blow away any previous mappings
3384 		 */
3385 		(void) as_unmap(as, *addrp, len);
3386 	}
3387 
3388 	vn_a.vp = vp;
3389 	vn_a.offset = (u_offset_t)off;
3390 	vn_a.type = flags & MAP_TYPE;
3391 	vn_a.prot = prot;
3392 	vn_a.maxprot = maxprot;
3393 	vn_a.cred = cr;
3394 	vn_a.amp = NULL;
3395 	vn_a.flags = flags & ~MAP_TYPE;
3396 	vn_a.szc = 0;
3397 	vn_a.lgrp_mem_policy_flags = 0;
3398 
3399 	error = as_map(as, *addrp, len, segvn_create, &vn_a);
3400 
3401 	as_rangeunlock(as);
3402 	ZFS_EXIT(zfsvfs);
3403 	return (error);
3404 }
3405 
3406 /* ARGSUSED */
3407 static int
3408 zfs_addmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr,
3409     size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, cred_t *cr)
3410 {
3411 	uint64_t pages = btopr(len);
3412 
3413 	atomic_add_64(&VTOZ(vp)->z_mapcnt, pages);
3414 	return (0);
3415 }
3416 
3417 /*
3418  * The reason we push dirty pages as part of zfs_delmap() is so that we get a
3419  * more accurate mtime for the associated file.  Since we don't have a way of
3420  * detecting when the data was actually modified, we have to resort to
3421  * heuristics.  If an explicit msync() is done, then we mark the mtime when the
3422  * last page is pushed.  The problem occurs when the msync() call is omitted,
3423  * which by far the most common case:
3424  *
3425  * 	open()
3426  * 	mmap()
3427  * 	<modify memory>
3428  * 	munmap()
3429  * 	close()
3430  * 	<time lapse>
3431  * 	putpage() via fsflush
3432  *
3433  * If we wait until fsflush to come along, we can have a modification time that
3434  * is some arbitrary point in the future.  In order to prevent this in the
3435  * common case, we flush pages whenever a (MAP_SHARED, PROT_WRITE) mapping is
3436  * torn down.
3437  */
3438 /* ARGSUSED */
3439 static int
3440 zfs_delmap(vnode_t *vp, offset_t off, struct as *as, caddr_t addr,
3441     size_t len, uint_t prot, uint_t maxprot, uint_t flags, cred_t *cr)
3442 {
3443 	uint64_t pages = btopr(len);
3444 
3445 	ASSERT3U(VTOZ(vp)->z_mapcnt, >=, pages);
3446 	atomic_add_64(&VTOZ(vp)->z_mapcnt, -pages);
3447 
3448 	if ((flags & MAP_SHARED) && (prot & PROT_WRITE) &&
3449 	    vn_has_cached_data(vp))
3450 		(void) VOP_PUTPAGE(vp, off, len, B_ASYNC, cr);
3451 
3452 	return (0);
3453 }
3454 
3455 /*
3456  * Free or allocate space in a file.  Currently, this function only
3457  * supports the `F_FREESP' command.  However, this command is somewhat
3458  * misnamed, as its functionality includes the ability to allocate as
3459  * well as free space.
3460  *
3461  *	IN:	vp	- vnode of file to free data in.
3462  *		cmd	- action to take (only F_FREESP supported).
3463  *		bfp	- section of file to free/alloc.
3464  *		flag	- current file open mode flags.
3465  *		offset	- current file offset.
3466  *		cr	- credentials of caller [UNUSED].
3467  *
3468  *	RETURN:	0 if success
3469  *		error code if failure
3470  *
3471  * Timestamps:
3472  *	vp - ctime|mtime updated
3473  */
3474 /* ARGSUSED */
3475 static int
3476 zfs_space(vnode_t *vp, int cmd, flock64_t *bfp, int flag,
3477     offset_t offset, cred_t *cr, caller_context_t *ct)
3478 {
3479 	znode_t		*zp = VTOZ(vp);
3480 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3481 	uint64_t	off, len;
3482 	int		error;
3483 
3484 	ZFS_ENTER(zfsvfs);
3485 
3486 top:
3487 	if (cmd != F_FREESP) {
3488 		ZFS_EXIT(zfsvfs);
3489 		return (EINVAL);
3490 	}
3491 
3492 	if (error = convoff(vp, bfp, 0, offset)) {
3493 		ZFS_EXIT(zfsvfs);
3494 		return (error);
3495 	}
3496 
3497 	if (bfp->l_len < 0) {
3498 		ZFS_EXIT(zfsvfs);
3499 		return (EINVAL);
3500 	}
3501 
3502 	off = bfp->l_start;
3503 	len = bfp->l_len; /* 0 means from off to end of file */
3504 
3505 	do {
3506 		error = zfs_freesp(zp, off, len, flag, TRUE);
3507 		/* NB: we already did dmu_tx_wait() if necessary */
3508 	} while (error == ERESTART && zfsvfs->z_assign == TXG_NOWAIT);
3509 
3510 	ZFS_EXIT(zfsvfs);
3511 	return (error);
3512 }
3513 
3514 static int
3515 zfs_fid(vnode_t *vp, fid_t *fidp)
3516 {
3517 	znode_t		*zp = VTOZ(vp);
3518 	zfsvfs_t	*zfsvfs = zp->z_zfsvfs;
3519 	uint32_t	gen = (uint32_t)zp->z_phys->zp_gen;
3520 	uint64_t	object = zp->z_id;
3521 	zfid_short_t	*zfid;
3522 	int		size, i;
3523 
3524 	ZFS_ENTER(zfsvfs);
3525 
3526 	size = (zfsvfs->z_parent != zfsvfs) ? LONG_FID_LEN : SHORT_FID_LEN;
3527 	if (fidp->fid_len < size) {
3528 		fidp->fid_len = size;
3529 		ZFS_EXIT(zfsvfs);
3530 		return (ENOSPC);
3531 	}
3532 
3533 	zfid = (zfid_short_t *)fidp;
3534 
3535 	zfid->zf_len = size;
3536 
3537 	for (i = 0; i < sizeof (zfid->zf_object); i++)
3538 		zfid->zf_object[i] = (uint8_t)(object >> (8 * i));
3539 
3540 	/* Must have a non-zero generation number to distinguish from .zfs */
3541 	if (gen == 0)
3542 		gen = 1;
3543 	for (i = 0; i < sizeof (zfid->zf_gen); i++)
3544 		zfid->zf_gen[i] = (uint8_t)(gen >> (8 * i));
3545 
3546 	if (size == LONG_FID_LEN) {
3547 		uint64_t	objsetid = dmu_objset_id(zfsvfs->z_os);
3548 		zfid_long_t	*zlfid;
3549 
3550 		zlfid = (zfid_long_t *)fidp;
3551 
3552 		for (i = 0; i < sizeof (zlfid->zf_setid); i++)
3553 			zlfid->zf_setid[i] = (uint8_t)(objsetid >> (8 * i));
3554 
3555 		/* XXX - this should be the generation number for the objset */
3556 		for (i = 0; i < sizeof (zlfid->zf_setgen); i++)
3557 			zlfid->zf_setgen[i] = 0;
3558 	}
3559 
3560 	ZFS_EXIT(zfsvfs);
3561 	return (0);
3562 }
3563 
3564 static int
3565 zfs_pathconf(vnode_t *vp, int cmd, ulong_t *valp, cred_t *cr)
3566 {
3567 	znode_t		*zp, *xzp;
3568 	zfsvfs_t	*zfsvfs;
3569 	zfs_dirlock_t	*dl;
3570 	int		error;
3571 
3572 	switch (cmd) {
3573 	case _PC_LINK_MAX:
3574 		*valp = ULONG_MAX;
3575 		return (0);
3576 
3577 	case _PC_FILESIZEBITS:
3578 		*valp = 64;
3579 		return (0);
3580 
3581 	case _PC_XATTR_EXISTS:
3582 		zp = VTOZ(vp);
3583 		zfsvfs = zp->z_zfsvfs;
3584 		ZFS_ENTER(zfsvfs);
3585 		*valp = 0;
3586 		error = zfs_dirent_lock(&dl, zp, "", &xzp,
3587 		    ZXATTR | ZEXISTS | ZSHARED);
3588 		if (error == 0) {
3589 			zfs_dirent_unlock(dl);
3590 			if (!zfs_dirempty(xzp))
3591 				*valp = 1;
3592 			VN_RELE(ZTOV(xzp));
3593 		} else if (error == ENOENT) {
3594 			/*
3595 			 * If there aren't extended attributes, it's the
3596 			 * same as having zero of them.
3597 			 */
3598 			error = 0;
3599 		}
3600 		ZFS_EXIT(zfsvfs);
3601 		return (error);
3602 
3603 	case _PC_ACL_ENABLED:
3604 		*valp = _ACL_ACE_ENABLED;
3605 		return (0);
3606 
3607 	case _PC_MIN_HOLE_SIZE:
3608 		*valp = (ulong_t)SPA_MINBLOCKSIZE;
3609 		return (0);
3610 
3611 	default:
3612 		return (fs_pathconf(vp, cmd, valp, cr));
3613 	}
3614 }
3615 
3616 /*ARGSUSED*/
3617 static int
3618 zfs_getsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr)
3619 {
3620 	znode_t *zp = VTOZ(vp);
3621 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3622 	int error;
3623 
3624 	ZFS_ENTER(zfsvfs);
3625 	error = zfs_getacl(zp, vsecp, cr);
3626 	ZFS_EXIT(zfsvfs);
3627 
3628 	return (error);
3629 }
3630 
3631 /*ARGSUSED*/
3632 static int
3633 zfs_setsecattr(vnode_t *vp, vsecattr_t *vsecp, int flag, cred_t *cr)
3634 {
3635 	znode_t *zp = VTOZ(vp);
3636 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
3637 	int error;
3638 
3639 	ZFS_ENTER(zfsvfs);
3640 	error = zfs_setacl(zp, vsecp, cr);
3641 	ZFS_EXIT(zfsvfs);
3642 	return (error);
3643 }
3644 
3645 /*
3646  * Predeclare these here so that the compiler assumes that
3647  * this is an "old style" function declaration that does
3648  * not include arguments => we won't get type mismatch errors
3649  * in the initializations that follow.
3650  */
3651 static int zfs_inval();
3652 static int zfs_isdir();
3653 
3654 static int
3655 zfs_inval()
3656 {
3657 	return (EINVAL);
3658 }
3659 
3660 static int
3661 zfs_isdir()
3662 {
3663 	return (EISDIR);
3664 }
3665 /*
3666  * Directory vnode operations template
3667  */
3668 vnodeops_t *zfs_dvnodeops;
3669 const fs_operation_def_t zfs_dvnodeops_template[] = {
3670 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
3671 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
3672 	VOPNAME_READ,		{ .error = zfs_isdir },
3673 	VOPNAME_WRITE,		{ .error = zfs_isdir },
3674 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
3675 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
3676 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
3677 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
3678 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
3679 	VOPNAME_CREATE,		{ .vop_create = zfs_create },
3680 	VOPNAME_REMOVE,		{ .vop_remove = zfs_remove },
3681 	VOPNAME_LINK,		{ .vop_link = zfs_link },
3682 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
3683 	VOPNAME_MKDIR,		{ .vop_mkdir = zfs_mkdir },
3684 	VOPNAME_RMDIR,		{ .vop_rmdir = zfs_rmdir },
3685 	VOPNAME_READDIR,	{ .vop_readdir = zfs_readdir },
3686 	VOPNAME_SYMLINK,	{ .vop_symlink = zfs_symlink },
3687 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
3688 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
3689 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
3690 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
3691 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
3692 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
3693 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
3694 	NULL,			NULL
3695 };
3696 
3697 /*
3698  * Regular file vnode operations template
3699  */
3700 vnodeops_t *zfs_fvnodeops;
3701 const fs_operation_def_t zfs_fvnodeops_template[] = {
3702 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
3703 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
3704 	VOPNAME_READ,		{ .vop_read = zfs_read },
3705 	VOPNAME_WRITE,		{ .vop_write = zfs_write },
3706 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
3707 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
3708 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
3709 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
3710 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
3711 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
3712 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
3713 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
3714 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
3715 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
3716 	VOPNAME_FRLOCK,		{ .vop_frlock = zfs_frlock },
3717 	VOPNAME_SPACE,		{ .vop_space = zfs_space },
3718 	VOPNAME_GETPAGE,	{ .vop_getpage = zfs_getpage },
3719 	VOPNAME_PUTPAGE,	{ .vop_putpage = zfs_putpage },
3720 	VOPNAME_MAP,		{ .vop_map = zfs_map },
3721 	VOPNAME_ADDMAP,		{ .vop_addmap = zfs_addmap },
3722 	VOPNAME_DELMAP,		{ .vop_delmap = zfs_delmap },
3723 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
3724 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
3725 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
3726 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
3727 	NULL,			NULL
3728 };
3729 
3730 /*
3731  * Symbolic link vnode operations template
3732  */
3733 vnodeops_t *zfs_symvnodeops;
3734 const fs_operation_def_t zfs_symvnodeops_template[] = {
3735 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
3736 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
3737 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
3738 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
3739 	VOPNAME_READLINK,	{ .vop_readlink = zfs_readlink },
3740 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
3741 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
3742 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
3743 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
3744 	NULL,			NULL
3745 };
3746 
3747 /*
3748  * Extended attribute directory vnode operations template
3749  *	This template is identical to the directory vnodes
3750  *	operation template except for restricted operations:
3751  *		VOP_MKDIR()
3752  *		VOP_SYMLINK()
3753  * Note that there are other restrictions embedded in:
3754  *	zfs_create()	- restrict type to VREG
3755  *	zfs_link()	- no links into/out of attribute space
3756  *	zfs_rename()	- no moves into/out of attribute space
3757  */
3758 vnodeops_t *zfs_xdvnodeops;
3759 const fs_operation_def_t zfs_xdvnodeops_template[] = {
3760 	VOPNAME_OPEN,		{ .vop_open = zfs_open },
3761 	VOPNAME_CLOSE,		{ .vop_close = zfs_close },
3762 	VOPNAME_IOCTL,		{ .vop_ioctl = zfs_ioctl },
3763 	VOPNAME_GETATTR,	{ .vop_getattr = zfs_getattr },
3764 	VOPNAME_SETATTR,	{ .vop_setattr = zfs_setattr },
3765 	VOPNAME_ACCESS,		{ .vop_access = zfs_access },
3766 	VOPNAME_LOOKUP,		{ .vop_lookup = zfs_lookup },
3767 	VOPNAME_CREATE,		{ .vop_create = zfs_create },
3768 	VOPNAME_REMOVE,		{ .vop_remove = zfs_remove },
3769 	VOPNAME_LINK,		{ .vop_link = zfs_link },
3770 	VOPNAME_RENAME,		{ .vop_rename = zfs_rename },
3771 	VOPNAME_MKDIR,		{ .error = zfs_inval },
3772 	VOPNAME_RMDIR,		{ .vop_rmdir = zfs_rmdir },
3773 	VOPNAME_READDIR,	{ .vop_readdir = zfs_readdir },
3774 	VOPNAME_SYMLINK,	{ .error = zfs_inval },
3775 	VOPNAME_FSYNC,		{ .vop_fsync = zfs_fsync },
3776 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
3777 	VOPNAME_FID,		{ .vop_fid = zfs_fid },
3778 	VOPNAME_SEEK,		{ .vop_seek = zfs_seek },
3779 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
3780 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = zfs_getsecattr },
3781 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = zfs_setsecattr },
3782 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
3783 	NULL,			NULL
3784 };
3785 
3786 /*
3787  * Error vnode operations template
3788  */
3789 vnodeops_t *zfs_evnodeops;
3790 const fs_operation_def_t zfs_evnodeops_template[] = {
3791 	VOPNAME_INACTIVE,	{ .vop_inactive = zfs_inactive },
3792 	VOPNAME_PATHCONF,	{ .vop_pathconf = zfs_pathconf },
3793 	NULL,			NULL
3794 };
3795