xref: /titanic_41/usr/src/uts/common/fs/fs_subr.c (revision e802abbda8c322f24d47835734f4a793ef15ddc8)
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 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
22 /*	  All Rights Reserved  	*/
23 
24 
25 /*
26  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 /*
31  * Generic vnode operations.
32  */
33 #include <sys/types.h>
34 #include <sys/param.h>
35 #include <sys/systm.h>
36 #include <sys/errno.h>
37 #include <sys/fcntl.h>
38 #include <sys/flock.h>
39 #include <sys/statvfs.h>
40 #include <sys/vfs.h>
41 #include <sys/vnode.h>
42 #include <sys/proc.h>
43 #include <sys/user.h>
44 #include <sys/unistd.h>
45 #include <sys/cred.h>
46 #include <sys/poll.h>
47 #include <sys/debug.h>
48 #include <sys/cmn_err.h>
49 #include <sys/stream.h>
50 #include <fs/fs_subr.h>
51 #include <sys/acl.h>
52 #include <sys/share.h>
53 #include <sys/file.h>
54 #include <sys/kmem.h>
55 #include <sys/file.h>
56 #include <sys/nbmlock.h>
57 #include <acl/acl_common.h>
58 
59 static callb_cpr_t *frlock_serialize_blocked(flk_cb_when_t, void *);
60 
61 /*
62  * Tunable to limit the number of retry to recover from STALE error.
63  */
64 int fs_estale_retry = 5;
65 
66 /*
67  * The associated operation is not supported by the file system.
68  */
69 int
70 fs_nosys()
71 {
72 	return (ENOSYS);
73 }
74 
75 /*
76  * The associated operation is invalid (on this vnode).
77  */
78 int
79 fs_inval()
80 {
81 	return (EINVAL);
82 }
83 
84 /*
85  * The associated operation is valid only for directories.
86  */
87 int
88 fs_notdir()
89 {
90 	return (ENOTDIR);
91 }
92 
93 /*
94  * Free the file system specific resources. For the file systems that
95  * do not support the forced unmount, it will be a nop function.
96  */
97 
98 /*ARGSUSED*/
99 void
100 fs_freevfs(vfs_t *vfsp)
101 {
102 }
103 
104 /* ARGSUSED */
105 int
106 fs_nosys_map(struct vnode *vp,
107 	offset_t off,
108 	struct as *as,
109 	caddr_t *addrp,
110 	size_t len,
111 	uchar_t prot,
112 	uchar_t maxprot,
113 	uint_t flags,
114 	struct cred *cr,
115 	caller_context_t *ct)
116 {
117 	return (ENOSYS);
118 }
119 
120 /* ARGSUSED */
121 int
122 fs_nosys_addmap(struct vnode *vp,
123 	offset_t off,
124 	struct as *as,
125 	caddr_t addr,
126 	size_t len,
127 	uchar_t prot,
128 	uchar_t maxprot,
129 	uint_t flags,
130 	struct cred *cr,
131 	caller_context_t *ct)
132 {
133 	return (ENOSYS);
134 }
135 
136 /* ARGSUSED */
137 int
138 fs_nosys_poll(vnode_t *vp,
139 	register short events,
140 	int anyyet,
141 	register short *reventsp,
142 	struct pollhead **phpp,
143 	caller_context_t *ct)
144 {
145 	return (ENOSYS);
146 }
147 
148 
149 /*
150  * The file system has nothing to sync to disk.  However, the
151  * VFS_SYNC operation must not fail.
152  */
153 /* ARGSUSED */
154 int
155 fs_sync(struct vfs *vfspp, short flag, cred_t *cr)
156 {
157 	return (0);
158 }
159 
160 /*
161  * Does nothing but VOP_FSYNC must not fail.
162  */
163 /* ARGSUSED */
164 int
165 fs_fsync(vnode_t *vp, int syncflag, cred_t *cr, caller_context_t *ct)
166 {
167 	return (0);
168 }
169 
170 /*
171  * Does nothing but VOP_PUTPAGE must not fail.
172  */
173 /* ARGSUSED */
174 int
175 fs_putpage(vnode_t *vp, offset_t off, size_t len, int flags, cred_t *cr,
176 	caller_context_t *ctp)
177 {
178 	return (0);
179 }
180 
181 /*
182  * Does nothing but VOP_IOCTL must not fail.
183  */
184 /* ARGSUSED */
185 int
186 fs_ioctl(vnode_t *vp, int com, intptr_t data, int flag, cred_t *cred,
187 	int *rvalp)
188 {
189 	return (0);
190 }
191 
192 /*
193  * Read/write lock/unlock.  Does nothing.
194  */
195 /* ARGSUSED */
196 int
197 fs_rwlock(vnode_t *vp, int write_lock, caller_context_t *ctp)
198 {
199 	return (-1);
200 }
201 
202 /* ARGSUSED */
203 void
204 fs_rwunlock(vnode_t *vp, int write_lock, caller_context_t *ctp)
205 {
206 }
207 
208 /*
209  * Compare two vnodes.
210  */
211 /*ARGSUSED2*/
212 int
213 fs_cmp(vnode_t *vp1, vnode_t *vp2, caller_context_t *ct)
214 {
215 	return (vp1 == vp2);
216 }
217 
218 /*
219  * No-op seek operation.
220  */
221 /* ARGSUSED */
222 int
223 fs_seek(vnode_t *vp, offset_t ooff, offset_t *noffp, caller_context_t *ct)
224 {
225 	return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
226 }
227 
228 /*
229  * File and record locking.
230  */
231 /* ARGSUSED */
232 int
233 fs_frlock(register vnode_t *vp, int cmd, struct flock64 *bfp, int flag,
234 	offset_t offset, flk_callback_t *flk_cbp, cred_t *cr,
235 	caller_context_t *ct)
236 {
237 	int frcmd;
238 	int nlmid;
239 	int error = 0;
240 	flk_callback_t serialize_callback;
241 	int serialize = 0;
242 	v_mode_t mode;
243 
244 	switch (cmd) {
245 
246 	case F_GETLK:
247 	case F_O_GETLK:
248 		if (flag & F_REMOTELOCK) {
249 			frcmd = RCMDLCK;
250 		} else if (flag & F_PXFSLOCK) {
251 			frcmd = PCMDLCK;
252 		} else {
253 			frcmd = 0;
254 			bfp->l_pid = ttoproc(curthread)->p_pid;
255 			bfp->l_sysid = 0;
256 		}
257 		break;
258 
259 	case F_SETLK_NBMAND:
260 		/*
261 		 * Are NBMAND locks allowed on this file?
262 		 */
263 		if (!vp->v_vfsp ||
264 		    !(vp->v_vfsp->vfs_flag & VFS_NBMAND)) {
265 			error = EINVAL;
266 			goto done;
267 		}
268 		if (vp->v_type != VREG) {
269 			error = EINVAL;
270 			goto done;
271 		}
272 		/*FALLTHROUGH*/
273 
274 	case F_SETLK:
275 		if (flag & F_REMOTELOCK) {
276 			frcmd = SETFLCK|RCMDLCK;
277 		} else if (flag & F_PXFSLOCK) {
278 			frcmd = SETFLCK|PCMDLCK;
279 		} else {
280 			frcmd = SETFLCK;
281 			bfp->l_pid = ttoproc(curthread)->p_pid;
282 			bfp->l_sysid = 0;
283 		}
284 		if (cmd == F_SETLK_NBMAND &&
285 		    (bfp->l_type == F_RDLCK || bfp->l_type == F_WRLCK)) {
286 			frcmd |= NBMLCK;
287 		}
288 
289 		if (nbl_need_check(vp)) {
290 			nbl_start_crit(vp, RW_WRITER);
291 			serialize = 1;
292 			if (frcmd & NBMLCK) {
293 				mode = (bfp->l_type == F_RDLCK) ?
294 				    V_READ : V_RDANDWR;
295 				if (vn_is_mapped(vp, mode)) {
296 					error = EAGAIN;
297 					goto done;
298 				}
299 			}
300 		}
301 		break;
302 
303 	case F_SETLKW:
304 		if (flag & F_REMOTELOCK) {
305 			frcmd = SETFLCK|SLPFLCK|RCMDLCK;
306 		} else if (flag & F_PXFSLOCK) {
307 			frcmd = SETFLCK|SLPFLCK|PCMDLCK;
308 		} else {
309 			frcmd = SETFLCK|SLPFLCK;
310 			bfp->l_pid = ttoproc(curthread)->p_pid;
311 			bfp->l_sysid = 0;
312 		}
313 
314 		if (nbl_need_check(vp)) {
315 			nbl_start_crit(vp, RW_WRITER);
316 			serialize = 1;
317 		}
318 		break;
319 
320 	case F_HASREMOTELOCKS:
321 		nlmid = GETNLMID(bfp->l_sysid);
322 		if (nlmid != 0) {	/* booted as a cluster */
323 			l_has_rmt(bfp) =
324 			    cl_flk_has_remote_locks_for_nlmid(vp, nlmid);
325 		} else {		/* not booted as a cluster */
326 			l_has_rmt(bfp) = flk_has_remote_locks(vp);
327 		}
328 
329 		goto done;
330 
331 	default:
332 		error = EINVAL;
333 		goto done;
334 	}
335 
336 	/*
337 	 * If this is a blocking lock request and we're serializing lock
338 	 * requests, modify the callback list to leave the critical region
339 	 * while we're waiting for the lock.
340 	 */
341 
342 	if (serialize && (frcmd & SLPFLCK) != 0) {
343 		flk_add_callback(&serialize_callback,
344 		    frlock_serialize_blocked, vp, flk_cbp);
345 		flk_cbp = &serialize_callback;
346 	}
347 
348 	error = reclock(vp, bfp, frcmd, flag, offset, flk_cbp);
349 
350 done:
351 	if (serialize)
352 		nbl_end_crit(vp);
353 
354 	return (error);
355 }
356 
357 /*
358  * Callback when a lock request blocks and we are serializing requests.  If
359  * before sleeping, leave the critical region.  If after wakeup, reenter
360  * the critical region.
361  */
362 
363 static callb_cpr_t *
364 frlock_serialize_blocked(flk_cb_when_t when, void *infop)
365 {
366 	vnode_t *vp = (vnode_t *)infop;
367 
368 	if (when == FLK_BEFORE_SLEEP)
369 		nbl_end_crit(vp);
370 	else {
371 		nbl_start_crit(vp, RW_WRITER);
372 	}
373 
374 	return (NULL);
375 }
376 
377 /*
378  * Allow any flags.
379  */
380 /* ARGSUSED */
381 int
382 fs_setfl(
383 	vnode_t *vp,
384 	int oflags,
385 	int nflags,
386 	cred_t *cr,
387 	caller_context_t *ct)
388 {
389 	return (0);
390 }
391 
392 /*
393  * Return the answer requested to poll() for non-device files.
394  * Only POLLIN, POLLRDNORM, and POLLOUT are recognized.
395  */
396 struct pollhead fs_pollhd;
397 
398 /* ARGSUSED */
399 int
400 fs_poll(vnode_t *vp,
401 	register short events,
402 	int anyyet,
403 	register short *reventsp,
404 	struct pollhead **phpp,
405 	caller_context_t *ct)
406 {
407 	*reventsp = 0;
408 	if (events & POLLIN)
409 		*reventsp |= POLLIN;
410 	if (events & POLLRDNORM)
411 		*reventsp |= POLLRDNORM;
412 	if (events & POLLRDBAND)
413 		*reventsp |= POLLRDBAND;
414 	if (events & POLLOUT)
415 		*reventsp |= POLLOUT;
416 	if (events & POLLWRBAND)
417 		*reventsp |= POLLWRBAND;
418 	*phpp = !anyyet && !*reventsp ? &fs_pollhd : (struct pollhead *)NULL;
419 	return (0);
420 }
421 
422 /*
423  * POSIX pathconf() support.
424  */
425 /* ARGSUSED */
426 int
427 fs_pathconf(
428 	vnode_t *vp,
429 	int cmd,
430 	ulong_t *valp,
431 	cred_t *cr,
432 	caller_context_t *ct)
433 {
434 	register ulong_t val;
435 	register int error = 0;
436 	struct statvfs64 vfsbuf;
437 
438 	switch (cmd) {
439 
440 	case _PC_LINK_MAX:
441 		val = MAXLINK;
442 		break;
443 
444 	case _PC_MAX_CANON:
445 		val = MAX_CANON;
446 		break;
447 
448 	case _PC_MAX_INPUT:
449 		val = MAX_INPUT;
450 		break;
451 
452 	case _PC_NAME_MAX:
453 		bzero(&vfsbuf, sizeof (vfsbuf));
454 		if (error = VFS_STATVFS(vp->v_vfsp, &vfsbuf))
455 			break;
456 		val = vfsbuf.f_namemax;
457 		break;
458 
459 	case _PC_PATH_MAX:
460 	case _PC_SYMLINK_MAX:
461 		val = MAXPATHLEN;
462 		break;
463 
464 	case _PC_PIPE_BUF:
465 		val = PIPE_BUF;
466 		break;
467 
468 	case _PC_NO_TRUNC:
469 		if (vp->v_vfsp->vfs_flag & VFS_NOTRUNC)
470 			val = 1;	/* NOTRUNC is enabled for vp */
471 		else
472 			val = (ulong_t)-1;
473 		break;
474 
475 	case _PC_VDISABLE:
476 		val = _POSIX_VDISABLE;
477 		break;
478 
479 	case _PC_CHOWN_RESTRICTED:
480 		if (rstchown)
481 			val = rstchown; /* chown restricted enabled */
482 		else
483 			val = (ulong_t)-1;
484 		break;
485 
486 	case _PC_FILESIZEBITS:
487 
488 		/*
489 		 * If ever we come here it means that underlying file system
490 		 * does not recognise the command and therefore this
491 		 * configurable limit cannot be determined. We return -1
492 		 * and don't change errno.
493 		 */
494 
495 		val = (ulong_t)-1;    /* large file support */
496 		break;
497 
498 	case _PC_ACL_ENABLED:
499 		val = 0;
500 		break;
501 
502 	case _PC_CASE_BEHAVIOR:
503 		val = _CASE_SENSITIVE;
504 		if (vfs_has_feature(vp->v_vfsp, VFSFT_CASEINSENSITIVE) == 1)
505 			val |= _CASE_INSENSITIVE;
506 		if (vfs_has_feature(vp->v_vfsp, VFSFT_NOCASESENSITIVE) == 1)
507 			val &= ~_CASE_SENSITIVE;
508 		break;
509 
510 	case _PC_SATTR_ENABLED:
511 	case _PC_SATTR_EXISTS:
512 		val = 0;
513 		break;
514 
515 	case _PC_ACCESS_FILTERING:
516 		val = 0;
517 		break;
518 
519 	default:
520 		error = EINVAL;
521 		break;
522 	}
523 
524 	if (error == 0)
525 		*valp = val;
526 	return (error);
527 }
528 
529 /*
530  * Dispose of a page.
531  */
532 /* ARGSUSED */
533 void
534 fs_dispose(
535 	struct vnode *vp,
536 	page_t *pp,
537 	int fl,
538 	int dn,
539 	struct cred *cr,
540 	caller_context_t *ct)
541 {
542 
543 	ASSERT(fl == B_FREE || fl == B_INVAL);
544 
545 	if (fl == B_FREE)
546 		page_free(pp, dn);
547 	else
548 		page_destroy(pp, dn);
549 }
550 
551 /* ARGSUSED */
552 void
553 fs_nodispose(
554 	struct vnode *vp,
555 	page_t *pp,
556 	int fl,
557 	int dn,
558 	struct cred *cr,
559 	caller_context_t *ct)
560 {
561 	cmn_err(CE_PANIC, "fs_nodispose invoked");
562 }
563 
564 /*
565  * fabricate acls for file systems that do not support acls.
566  */
567 /* ARGSUSED */
568 int
569 fs_fab_acl(
570 	vnode_t *vp,
571 	vsecattr_t *vsecattr,
572 	int flag,
573 	cred_t *cr,
574 	caller_context_t *ct)
575 {
576 	aclent_t	*aclentp;
577 	ace_t		*acep;
578 	struct vattr	vattr;
579 	int		error;
580 	size_t		aclsize;
581 
582 	vsecattr->vsa_aclcnt	= 0;
583 	vsecattr->vsa_aclentsz	= 0;
584 	vsecattr->vsa_aclentp	= NULL;
585 	vsecattr->vsa_dfaclcnt	= 0;	/* Default ACLs are not fabricated */
586 	vsecattr->vsa_dfaclentp	= NULL;
587 
588 	vattr.va_mask = AT_MODE | AT_UID | AT_GID;
589 	if (error = VOP_GETATTR(vp, &vattr, 0, cr, ct))
590 		return (error);
591 
592 	if (vsecattr->vsa_mask & (VSA_ACLCNT | VSA_ACL)) {
593 		aclsize = 4 * sizeof (aclent_t);
594 		vsecattr->vsa_aclcnt	= 4; /* USER, GROUP, OTHER, and CLASS */
595 		vsecattr->vsa_aclentp = kmem_zalloc(aclsize, KM_SLEEP);
596 		aclentp = vsecattr->vsa_aclentp;
597 
598 		aclentp->a_type = USER_OBJ;	/* Owner */
599 		aclentp->a_perm = ((ushort_t)(vattr.va_mode & 0700)) >> 6;
600 		aclentp->a_id = vattr.va_uid;   /* Really undefined */
601 		aclentp++;
602 
603 		aclentp->a_type = GROUP_OBJ;    /* Group */
604 		aclentp->a_perm = ((ushort_t)(vattr.va_mode & 0070)) >> 3;
605 		aclentp->a_id = vattr.va_gid;   /* Really undefined */
606 		aclentp++;
607 
608 		aclentp->a_type = OTHER_OBJ;    /* Other */
609 		aclentp->a_perm = vattr.va_mode & 0007;
610 		aclentp->a_id = (gid_t)-1;	/* Really undefined */
611 		aclentp++;
612 
613 		aclentp->a_type = CLASS_OBJ;    /* Class */
614 		aclentp->a_perm = (ushort_t)(0007);
615 		aclentp->a_id = (gid_t)-1;	/* Really undefined */
616 	} else if (vsecattr->vsa_mask & (VSA_ACECNT | VSA_ACE)) {
617 		aclsize = 6 * sizeof (ace_t);
618 		vsecattr->vsa_aclcnt	= 6;
619 		vsecattr->vsa_aclentp = kmem_zalloc(aclsize, KM_SLEEP);
620 		vsecattr->vsa_aclentsz = aclsize;
621 		acep = vsecattr->vsa_aclentp;
622 		(void) memcpy(acep, trivial_acl, sizeof (ace_t) * 6);
623 		adjust_ace_pair(acep, (vattr.va_mode & 0700) >> 6);
624 		adjust_ace_pair(acep + 2, (vattr.va_mode & 0070) >> 3);
625 		adjust_ace_pair(acep + 4, vattr.va_mode & 0007);
626 	}
627 
628 	return (0);
629 }
630 
631 /*
632  * Common code for implementing DOS share reservations
633  */
634 /* ARGSUSED4 */
635 int
636 fs_shrlock(
637 	struct vnode *vp,
638 	int cmd,
639 	struct shrlock *shr,
640 	int flag,
641 	cred_t *cr,
642 	caller_context_t *ct)
643 {
644 	int error;
645 
646 	/*
647 	 * Make sure that the file was opened with permissions appropriate
648 	 * for the request, and make sure the caller isn't trying to sneak
649 	 * in an NBMAND request.
650 	 */
651 	if (cmd == F_SHARE) {
652 		if (((shr->s_access & F_RDACC) && (flag & FREAD) == 0) ||
653 		    ((shr->s_access & F_WRACC) && (flag & FWRITE) == 0))
654 			return (EBADF);
655 		if (shr->s_access & (F_RMACC | F_MDACC))
656 			return (EINVAL);
657 		if (shr->s_deny & (F_MANDDNY | F_RMDNY))
658 			return (EINVAL);
659 	}
660 	if (cmd == F_SHARE_NBMAND) {
661 		/* make sure nbmand is allowed on the file */
662 		if (!vp->v_vfsp ||
663 		    !(vp->v_vfsp->vfs_flag & VFS_NBMAND)) {
664 			return (EINVAL);
665 		}
666 		if (vp->v_type != VREG) {
667 			return (EINVAL);
668 		}
669 	}
670 
671 	nbl_start_crit(vp, RW_WRITER);
672 
673 	switch (cmd) {
674 
675 	case F_SHARE_NBMAND:
676 		shr->s_deny |= F_MANDDNY;
677 		/*FALLTHROUGH*/
678 	case F_SHARE:
679 		error = add_share(vp, shr);
680 		break;
681 
682 	case F_UNSHARE:
683 		error = del_share(vp, shr);
684 		break;
685 
686 	case F_HASREMOTELOCKS:
687 		/*
688 		 * We are overloading this command to refer to remote
689 		 * shares as well as remote locks, despite its name.
690 		 */
691 		shr->s_access = shr_has_remote_shares(vp, shr->s_sysid);
692 		error = 0;
693 		break;
694 
695 	default:
696 		error = EINVAL;
697 		break;
698 	}
699 
700 	nbl_end_crit(vp);
701 	return (error);
702 }
703 
704 /*ARGSUSED1*/
705 int
706 fs_vnevent_nosupport(vnode_t *vp, vnevent_t e, vnode_t *dvp, char *fnm,
707     caller_context_t *ct)
708 {
709 	ASSERT(vp != NULL);
710 	return (ENOTSUP);
711 }
712 
713 /*ARGSUSED1*/
714 int
715 fs_vnevent_support(vnode_t *vp, vnevent_t e, vnode_t *dvp, char *fnm,
716     caller_context_t *ct)
717 {
718 	ASSERT(vp != NULL);
719 	return (0);
720 }
721 
722 /*
723  * return 1 for non-trivial ACL.
724  *
725  * NB: It is not necessary for the caller to VOP_RWLOCK since
726  *	we only issue VOP_GETSECATTR.
727  *
728  * Returns 0 == trivial
729  *         1 == NOT Trivial
730  *	   <0 could not determine.
731  */
732 int
733 fs_acl_nontrivial(vnode_t *vp, cred_t *cr)
734 {
735 	ulong_t		acl_styles;
736 	ulong_t		acl_flavor;
737 	vsecattr_t 	vsecattr;
738 	int 		error;
739 	int		isnontrivial;
740 
741 	/* determine the forms of ACLs maintained */
742 	error = VOP_PATHCONF(vp, _PC_ACL_ENABLED, &acl_styles, cr, NULL);
743 
744 	/* clear bits we don't understand and establish default acl_style */
745 	acl_styles &= (_ACL_ACLENT_ENABLED | _ACL_ACE_ENABLED);
746 	if (error || (acl_styles == 0))
747 		acl_styles = _ACL_ACLENT_ENABLED;
748 
749 	vsecattr.vsa_aclentp = NULL;
750 	vsecattr.vsa_dfaclentp = NULL;
751 	vsecattr.vsa_aclcnt = 0;
752 	vsecattr.vsa_dfaclcnt = 0;
753 
754 	while (acl_styles) {
755 		/* select one of the styles as current flavor */
756 		acl_flavor = 0;
757 		if (acl_styles & _ACL_ACLENT_ENABLED) {
758 			acl_flavor = _ACL_ACLENT_ENABLED;
759 			vsecattr.vsa_mask = VSA_ACLCNT | VSA_DFACLCNT;
760 		} else if (acl_styles & _ACL_ACE_ENABLED) {
761 			acl_flavor = _ACL_ACE_ENABLED;
762 			vsecattr.vsa_mask = VSA_ACECNT | VSA_ACE;
763 		}
764 
765 		ASSERT(vsecattr.vsa_mask && acl_flavor);
766 		error = VOP_GETSECATTR(vp, &vsecattr, 0, cr, NULL);
767 		if (error == 0)
768 			break;
769 
770 		/* that flavor failed */
771 		acl_styles &= ~acl_flavor;
772 	}
773 
774 	/* if all styles fail then assume trivial */
775 	if (acl_styles == 0)
776 		return (0);
777 
778 	/* process the flavor that worked */
779 	isnontrivial = 0;
780 	if (acl_flavor & _ACL_ACLENT_ENABLED) {
781 		if (vsecattr.vsa_aclcnt > MIN_ACL_ENTRIES)
782 			isnontrivial = 1;
783 		if (vsecattr.vsa_aclcnt && vsecattr.vsa_aclentp != NULL)
784 			kmem_free(vsecattr.vsa_aclentp,
785 			    vsecattr.vsa_aclcnt * sizeof (aclent_t));
786 		if (vsecattr.vsa_dfaclcnt && vsecattr.vsa_dfaclentp != NULL)
787 			kmem_free(vsecattr.vsa_dfaclentp,
788 			    vsecattr.vsa_dfaclcnt * sizeof (aclent_t));
789 	}
790 	if (acl_flavor & _ACL_ACE_ENABLED) {
791 
792 		isnontrivial = ace_trivial(vsecattr.vsa_aclentp,
793 		    vsecattr.vsa_aclcnt);
794 
795 		if (vsecattr.vsa_aclcnt && vsecattr.vsa_aclentp != NULL)
796 			kmem_free(vsecattr.vsa_aclentp,
797 			    vsecattr.vsa_aclcnt * sizeof (ace_t));
798 		/* ACE has no vsecattr.vsa_dfaclcnt */
799 	}
800 	return (isnontrivial);
801 }
802 
803 /*
804  * Check whether we need a retry to recover from STALE error.
805  */
806 int
807 fs_need_estale_retry(int retry_count)
808 {
809 	if (retry_count < fs_estale_retry)
810 		return (1);
811 	else
812 		return (0);
813 }
814 
815 
816 static int (*fs_av_scan)(vnode_t *, cred_t *, int) = NULL;
817 
818 /*
819  * Routine for anti-virus scanner to call to register its scanning routine.
820  */
821 void
822 fs_vscan_register(int (*av_scan)(vnode_t *, cred_t *, int))
823 {
824 	fs_av_scan = av_scan;
825 }
826 
827 /*
828  * Routine for file systems to call to initiate anti-virus scanning.
829  * Scanning will only be done on REGular files (currently).
830  */
831 int
832 fs_vscan(vnode_t *vp, cred_t *cr, int async)
833 {
834 	int ret = 0;
835 
836 	if (fs_av_scan && vp->v_type == VREG)
837 		ret = (*fs_av_scan)(vp, cr, async);
838 
839 	return (ret);
840 }
841