xref: /illumos-gate/usr/src/uts/common/fs/ufs/ufs_vnops.c (revision 1769817e9676d2db341d2b6828c199f0eabac823)
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 /*
23  * Copyright (c) 1984, 2010, Oracle and/or its affiliates. All rights reserved.
24  * Copyright 2018 Joyent, Inc.
25  * Copyright (c) 2016 by Delphix. All rights reserved.
26  */
27 
28 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
29 /*	  All Rights Reserved	*/
30 
31 /*
32  * Portions of this source code were derived from Berkeley 4.3 BSD
33  * under license from the Regents of the University of California.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/t_lock.h>
38 #include <sys/ksynch.h>
39 #include <sys/param.h>
40 #include <sys/time.h>
41 #include <sys/systm.h>
42 #include <sys/sysmacros.h>
43 #include <sys/resource.h>
44 #include <sys/signal.h>
45 #include <sys/cred.h>
46 #include <sys/user.h>
47 #include <sys/buf.h>
48 #include <sys/vfs.h>
49 #include <sys/vfs_opreg.h>
50 #include <sys/vnode.h>
51 #include <sys/proc.h>
52 #include <sys/disp.h>
53 #include <sys/file.h>
54 #include <sys/fcntl.h>
55 #include <sys/flock.h>
56 #include <sys/atomic.h>
57 #include <sys/kmem.h>
58 #include <sys/uio.h>
59 #include <sys/dnlc.h>
60 #include <sys/conf.h>
61 #include <sys/mman.h>
62 #include <sys/pathname.h>
63 #include <sys/debug.h>
64 #include <sys/vmsystm.h>
65 #include <sys/cmn_err.h>
66 #include <sys/filio.h>
67 #include <sys/policy.h>
68 
69 #include <sys/fs/ufs_fs.h>
70 #include <sys/fs/ufs_lockfs.h>
71 #include <sys/fs/ufs_filio.h>
72 #include <sys/fs/ufs_inode.h>
73 #include <sys/fs/ufs_fsdir.h>
74 #include <sys/fs/ufs_quota.h>
75 #include <sys/fs/ufs_log.h>
76 #include <sys/fs/ufs_snap.h>
77 #include <sys/fs/ufs_trans.h>
78 #include <sys/fs/ufs_panic.h>
79 #include <sys/fs/ufs_bio.h>
80 #include <sys/dirent.h>		/* must be AFTER <sys/fs/fsdir.h>! */
81 #include <sys/errno.h>
82 #include <sys/fssnap_if.h>
83 #include <sys/unistd.h>
84 #include <sys/sunddi.h>
85 
86 #include <sys/filio.h>		/* _FIOIO */
87 
88 #include <vm/hat.h>
89 #include <vm/page.h>
90 #include <vm/pvn.h>
91 #include <vm/as.h>
92 #include <vm/seg.h>
93 #include <vm/seg_map.h>
94 #include <vm/seg_vn.h>
95 #include <vm/seg_kmem.h>
96 #include <vm/rm.h>
97 #include <sys/swap.h>
98 
99 #include <fs/fs_subr.h>
100 
101 #include <sys/fs/decomp.h>
102 
103 static struct instats ins;
104 
105 static	int ufs_getpage_ra(struct vnode *, u_offset_t, struct seg *, caddr_t);
106 static	int ufs_getpage_miss(struct vnode *, u_offset_t, size_t, struct seg *,
107 		caddr_t, struct page **, size_t, enum seg_rw, int);
108 static	int ufs_open(struct vnode **, int, struct cred *, caller_context_t *);
109 static	int ufs_close(struct vnode *, int, int, offset_t, struct cred *,
110 		caller_context_t *);
111 static	int ufs_read(struct vnode *, struct uio *, int, struct cred *,
112 		struct caller_context *);
113 static	int ufs_write(struct vnode *, struct uio *, int, struct cred *,
114 		struct caller_context *);
115 static	int ufs_ioctl(struct vnode *, int, intptr_t, int, struct cred *,
116 		int *, caller_context_t *);
117 static	int ufs_getattr(struct vnode *, struct vattr *, int, struct cred *,
118 		caller_context_t *);
119 static	int ufs_setattr(struct vnode *, struct vattr *, int, struct cred *,
120 		caller_context_t *);
121 static	int ufs_access(struct vnode *, int, int, struct cred *,
122 		caller_context_t *);
123 static	int ufs_lookup(struct vnode *, char *, struct vnode **,
124 		struct pathname *, int, struct vnode *, struct cred *,
125 		caller_context_t *, int *, pathname_t *);
126 static	int ufs_create(struct vnode *, char *, struct vattr *, enum vcexcl,
127 		int, struct vnode **, struct cred *, int,
128 		caller_context_t *, vsecattr_t  *);
129 static	int ufs_remove(struct vnode *, char *, struct cred *,
130 		caller_context_t *, int);
131 static	int ufs_link(struct vnode *, struct vnode *, char *, struct cred *,
132 		caller_context_t *, int);
133 static	int ufs_rename(struct vnode *, char *, struct vnode *, char *,
134 		struct cred *, caller_context_t *, int);
135 static	int ufs_mkdir(struct vnode *, char *, struct vattr *, struct vnode **,
136 		struct cred *, caller_context_t *, int, vsecattr_t *);
137 static	int ufs_rmdir(struct vnode *, char *, struct vnode *, struct cred *,
138 		caller_context_t *, int);
139 static	int ufs_readdir(struct vnode *, struct uio *, struct cred *, int *,
140 		caller_context_t *, int);
141 static	int ufs_symlink(struct vnode *, char *, struct vattr *, char *,
142 		struct cred *, caller_context_t *, int);
143 static	int ufs_readlink(struct vnode *, struct uio *, struct cred *,
144 		caller_context_t *);
145 static	int ufs_fsync(struct vnode *, int, struct cred *, caller_context_t *);
146 static	void ufs_inactive(struct vnode *, struct cred *, caller_context_t *);
147 static	int ufs_fid(struct vnode *, struct fid *, caller_context_t *);
148 static	int ufs_rwlock(struct vnode *, int, caller_context_t *);
149 static	void ufs_rwunlock(struct vnode *, int, caller_context_t *);
150 static	int ufs_seek(struct vnode *, offset_t, offset_t *, caller_context_t *);
151 static	int ufs_frlock(struct vnode *, int, struct flock64 *, int, offset_t,
152 		struct flk_callback *, struct cred *,
153 		caller_context_t *);
154 static  int ufs_space(struct vnode *, int, struct flock64 *, int, offset_t,
155 		cred_t *, caller_context_t *);
156 static	int ufs_getpage(struct vnode *, offset_t, size_t, uint_t *,
157 		struct page **, size_t, struct seg *, caddr_t,
158 		enum seg_rw, struct cred *, caller_context_t *);
159 static	int ufs_putpage(struct vnode *, offset_t, size_t, int, struct cred *,
160 		caller_context_t *);
161 static	int ufs_putpages(struct vnode *, offset_t, size_t, int, struct cred *);
162 static	int ufs_map(struct vnode *, offset_t, struct as *, caddr_t *, size_t,
163 		uchar_t, uchar_t, uint_t, struct cred *, caller_context_t *);
164 static	int ufs_addmap(struct vnode *, offset_t, struct as *, caddr_t,  size_t,
165 		uchar_t, uchar_t, uint_t, struct cred *, caller_context_t *);
166 static	int ufs_delmap(struct vnode *, offset_t, struct as *, caddr_t,  size_t,
167 		uint_t, uint_t, uint_t, struct cred *, caller_context_t *);
168 static	int ufs_poll(vnode_t *, short, int, short *, struct pollhead **,
169 		caller_context_t *);
170 static	int ufs_dump(vnode_t *, caddr_t, offset_t, offset_t,
171     caller_context_t *);
172 static	int ufs_l_pathconf(struct vnode *, int, ulong_t *, struct cred *,
173 		caller_context_t *);
174 static	int ufs_pageio(struct vnode *, struct page *, u_offset_t, size_t, int,
175 		struct cred *, caller_context_t *);
176 static	int ufs_dumpctl(vnode_t *, int, offset_t *, caller_context_t *);
177 static	daddr32_t *save_dblks(struct inode *, struct ufsvfs *, daddr32_t *,
178 		daddr32_t *, int, int);
179 static	int ufs_getsecattr(struct vnode *, vsecattr_t *, int, struct cred *,
180 		caller_context_t *);
181 static	int ufs_setsecattr(struct vnode *, vsecattr_t *, int, struct cred *,
182 		caller_context_t *);
183 static	int ufs_priv_access(void *, int, struct cred *);
184 static	int ufs_eventlookup(struct vnode *, char *, struct cred *,
185     struct vnode **);
186 
187 /*
188  * For lockfs: ulockfs begin/end is now inlined in the ufs_xxx functions.
189  *
190  * XXX - ULOCKFS in fs_pathconf and ufs_ioctl is not inlined yet.
191  */
192 struct vnodeops *ufs_vnodeops;
193 
194 /* NOTE: "not blkd" below  means that the operation isn't blocked by lockfs */
195 const fs_operation_def_t ufs_vnodeops_template[] = {
196 	VOPNAME_OPEN,		{ .vop_open = ufs_open },	/* not blkd */
197 	VOPNAME_CLOSE,		{ .vop_close = ufs_close },	/* not blkd */
198 	VOPNAME_READ,		{ .vop_read = ufs_read },
199 	VOPNAME_WRITE,		{ .vop_write = ufs_write },
200 	VOPNAME_IOCTL,		{ .vop_ioctl = ufs_ioctl },
201 	VOPNAME_GETATTR,	{ .vop_getattr = ufs_getattr },
202 	VOPNAME_SETATTR,	{ .vop_setattr = ufs_setattr },
203 	VOPNAME_ACCESS,		{ .vop_access = ufs_access },
204 	VOPNAME_LOOKUP,		{ .vop_lookup = ufs_lookup },
205 	VOPNAME_CREATE,		{ .vop_create = ufs_create },
206 	VOPNAME_REMOVE,		{ .vop_remove = ufs_remove },
207 	VOPNAME_LINK,		{ .vop_link = ufs_link },
208 	VOPNAME_RENAME,		{ .vop_rename = ufs_rename },
209 	VOPNAME_MKDIR,		{ .vop_mkdir = ufs_mkdir },
210 	VOPNAME_RMDIR,		{ .vop_rmdir = ufs_rmdir },
211 	VOPNAME_READDIR,	{ .vop_readdir = ufs_readdir },
212 	VOPNAME_SYMLINK,	{ .vop_symlink = ufs_symlink },
213 	VOPNAME_READLINK,	{ .vop_readlink = ufs_readlink },
214 	VOPNAME_FSYNC,		{ .vop_fsync = ufs_fsync },
215 	VOPNAME_INACTIVE,	{ .vop_inactive = ufs_inactive }, /* not blkd */
216 	VOPNAME_FID,		{ .vop_fid = ufs_fid },
217 	VOPNAME_RWLOCK,		{ .vop_rwlock = ufs_rwlock },	/* not blkd */
218 	VOPNAME_RWUNLOCK,	{ .vop_rwunlock = ufs_rwunlock }, /* not blkd */
219 	VOPNAME_SEEK,		{ .vop_seek = ufs_seek },
220 	VOPNAME_FRLOCK,		{ .vop_frlock = ufs_frlock },
221 	VOPNAME_SPACE,		{ .vop_space = ufs_space },
222 	VOPNAME_GETPAGE,	{ .vop_getpage = ufs_getpage },
223 	VOPNAME_PUTPAGE,	{ .vop_putpage = ufs_putpage },
224 	VOPNAME_MAP,		{ .vop_map = ufs_map },
225 	VOPNAME_ADDMAP,		{ .vop_addmap = ufs_addmap },	/* not blkd */
226 	VOPNAME_DELMAP,		{ .vop_delmap = ufs_delmap },	/* not blkd */
227 	VOPNAME_POLL,		{ .vop_poll = ufs_poll },	/* not blkd */
228 	VOPNAME_DUMP,		{ .vop_dump = ufs_dump },
229 	VOPNAME_PATHCONF,	{ .vop_pathconf = ufs_l_pathconf },
230 	VOPNAME_PAGEIO,		{ .vop_pageio = ufs_pageio },
231 	VOPNAME_DUMPCTL,	{ .vop_dumpctl = ufs_dumpctl },
232 	VOPNAME_GETSECATTR,	{ .vop_getsecattr = ufs_getsecattr },
233 	VOPNAME_SETSECATTR,	{ .vop_setsecattr = ufs_setsecattr },
234 	VOPNAME_VNEVENT,	{ .vop_vnevent = fs_vnevent_support },
235 	NULL,			NULL
236 };
237 
238 #define	MAX_BACKFILE_COUNT	9999
239 
240 /*
241  * Created by ufs_dumpctl() to store a file's disk block info into memory.
242  * Used by ufs_dump() to dump data to disk directly.
243  */
244 struct dump {
245 	struct inode	*ip;		/* the file we contain */
246 	daddr_t		fsbs;		/* number of blocks stored */
247 	struct timeval32 time;		/* time stamp for the struct */
248 	daddr32_t	dblk[1];	/* place holder for block info */
249 };
250 
251 static struct dump *dump_info = NULL;
252 
253 /*
254  * Previously there was no special action required for ordinary files.
255  * (Devices are handled through the device file system.)
256  * Now we support Large Files and Large File API requires open to
257  * fail if file is large.
258  * We could take care to prevent data corruption
259  * by doing an atomic check of size and truncate if file is opened with
260  * FTRUNC flag set but traditionally this is being done by the vfs/vnode
261  * layers. So taking care of truncation here is a change in the existing
262  * semantics of VOP_OPEN and therefore we chose not to implement any thing
263  * here. The check for the size of the file > 2GB is being done at the
264  * vfs layer in routine vn_open().
265  */
266 
267 /* ARGSUSED */
268 static int
269 ufs_open(struct vnode **vpp, int flag, struct cred *cr, caller_context_t *ct)
270 {
271 	return (0);
272 }
273 
274 /*ARGSUSED*/
275 static int
276 ufs_close(struct vnode *vp, int flag, int count, offset_t offset,
277     struct cred *cr, caller_context_t *ct)
278 {
279 	cleanlocks(vp, ttoproc(curthread)->p_pid, 0);
280 	cleanshares(vp, ttoproc(curthread)->p_pid);
281 
282 	/*
283 	 * Push partially filled cluster at last close.
284 	 * ``last close'' is approximated because the dnlc
285 	 * may have a hold on the vnode.
286 	 * Checking for VBAD here will also act as a forced umount check.
287 	 */
288 	if (vp->v_count <= 2 && vp->v_type != VBAD) {
289 		struct inode *ip = VTOI(vp);
290 		if (ip->i_delaylen) {
291 			ins.in_poc.value.ul++;
292 			(void) ufs_putpages(vp, ip->i_delayoff, ip->i_delaylen,
293 			    B_ASYNC | B_FREE, cr);
294 			ip->i_delaylen = 0;
295 		}
296 	}
297 
298 	return (0);
299 }
300 
301 /*ARGSUSED*/
302 static int
303 ufs_read(struct vnode *vp, struct uio *uiop, int ioflag, struct cred *cr,
304     struct caller_context *ct)
305 {
306 	struct inode *ip = VTOI(vp);
307 	struct ufsvfs *ufsvfsp;
308 	struct ulockfs *ulp = NULL;
309 	int error = 0;
310 	int intrans = 0;
311 
312 	ASSERT(RW_READ_HELD(&ip->i_rwlock));
313 
314 	/*
315 	 * Mandatory locking needs to be done before ufs_lockfs_begin()
316 	 * and TRANS_BEGIN_SYNC() calls since mandatory locks can sleep.
317 	 */
318 	if (MANDLOCK(vp, ip->i_mode)) {
319 		/*
320 		 * ufs_getattr ends up being called by chklock
321 		 */
322 		error = chklock(vp, FREAD, uiop->uio_loffset,
323 		    uiop->uio_resid, uiop->uio_fmode, ct);
324 		if (error)
325 			goto out;
326 	}
327 
328 	ufsvfsp = ip->i_ufsvfs;
329 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_READ_MASK);
330 	if (error)
331 		goto out;
332 
333 	/*
334 	 * In the case that a directory is opened for reading as a file
335 	 * (eg "cat .") with the  O_RSYNC, O_SYNC and O_DSYNC flags set.
336 	 * The locking order had to be changed to avoid a deadlock with
337 	 * an update taking place on that directory at the same time.
338 	 */
339 	if ((ip->i_mode & IFMT) == IFDIR) {
340 
341 		rw_enter(&ip->i_contents, RW_READER);
342 		error = rdip(ip, uiop, ioflag, cr);
343 		rw_exit(&ip->i_contents);
344 
345 		if (error) {
346 			if (ulp)
347 				ufs_lockfs_end(ulp);
348 			goto out;
349 		}
350 
351 		if (ulp && (ioflag & FRSYNC) && (ioflag & (FSYNC | FDSYNC)) &&
352 		    TRANS_ISTRANS(ufsvfsp)) {
353 			rw_exit(&ip->i_rwlock);
354 			TRANS_BEGIN_SYNC(ufsvfsp, TOP_READ_SYNC, TOP_READ_SIZE,
355 			    error);
356 			ASSERT(!error);
357 			TRANS_END_SYNC(ufsvfsp, error, TOP_READ_SYNC,
358 			    TOP_READ_SIZE);
359 			rw_enter(&ip->i_rwlock, RW_READER);
360 		}
361 	} else {
362 		/*
363 		 * Only transact reads to files opened for sync-read and
364 		 * sync-write on a file system that is not write locked.
365 		 *
366 		 * The ``not write locked'' check prevents problems with
367 		 * enabling/disabling logging on a busy file system.  E.g.,
368 		 * logging exists at the beginning of the read but does not
369 		 * at the end.
370 		 *
371 		 */
372 		if (ulp && (ioflag & FRSYNC) && (ioflag & (FSYNC | FDSYNC)) &&
373 		    TRANS_ISTRANS(ufsvfsp)) {
374 			TRANS_BEGIN_SYNC(ufsvfsp, TOP_READ_SYNC, TOP_READ_SIZE,
375 			    error);
376 			ASSERT(!error);
377 			intrans = 1;
378 		}
379 
380 		rw_enter(&ip->i_contents, RW_READER);
381 		error = rdip(ip, uiop, ioflag, cr);
382 		rw_exit(&ip->i_contents);
383 
384 		if (intrans) {
385 			TRANS_END_SYNC(ufsvfsp, error, TOP_READ_SYNC,
386 			    TOP_READ_SIZE);
387 		}
388 	}
389 
390 	if (ulp) {
391 		ufs_lockfs_end(ulp);
392 	}
393 out:
394 
395 	return (error);
396 }
397 
398 extern	int	ufs_HW;		/* high water mark */
399 extern	int	ufs_LW;		/* low water mark */
400 int	ufs_WRITES = 1;		/* XXX - enable/disable */
401 int	ufs_throttles = 0;	/* throttling count */
402 int	ufs_allow_shared_writes = 1;	/* directio shared writes */
403 
404 static int
405 ufs_check_rewrite(struct inode *ip, struct uio *uiop, int ioflag)
406 {
407 	int	shared_write;
408 
409 	/*
410 	 * If the FDSYNC flag is set then ignore the global
411 	 * ufs_allow_shared_writes in this case.
412 	 */
413 	shared_write = (ioflag & FDSYNC) | ufs_allow_shared_writes;
414 
415 	/*
416 	 * Filter to determine if this request is suitable as a
417 	 * concurrent rewrite. This write must not allocate blocks
418 	 * by extending the file or filling in holes. No use trying
419 	 * through FSYNC descriptors as the inode will be synchronously
420 	 * updated after the write. The uio structure has not yet been
421 	 * checked for sanity, so assume nothing.
422 	 */
423 	return (((ip->i_mode & IFMT) == IFREG) && !(ioflag & FAPPEND) &&
424 	    (uiop->uio_loffset >= (offset_t)0) &&
425 	    (uiop->uio_loffset < ip->i_size) && (uiop->uio_resid > 0) &&
426 	    ((ip->i_size - uiop->uio_loffset) >= uiop->uio_resid) &&
427 	    !(ioflag & FSYNC) && !bmap_has_holes(ip) &&
428 	    shared_write);
429 }
430 
431 /*ARGSUSED*/
432 static int
433 ufs_write(struct vnode *vp, struct uio *uiop, int ioflag, cred_t *cr,
434     caller_context_t *ct)
435 {
436 	struct inode *ip = VTOI(vp);
437 	struct ufsvfs *ufsvfsp;
438 	struct ulockfs *ulp;
439 	int retry = 1;
440 	int error, resv, resid = 0;
441 	int directio_status;
442 	int exclusive;
443 	int rewriteflg;
444 	long start_resid = uiop->uio_resid;
445 
446 	ASSERT(RW_LOCK_HELD(&ip->i_rwlock));
447 
448 retry_mandlock:
449 	/*
450 	 * Mandatory locking needs to be done before ufs_lockfs_begin()
451 	 * and TRANS_BEGIN_[A]SYNC() calls since mandatory locks can sleep.
452 	 * Check for forced unmounts normally done in ufs_lockfs_begin().
453 	 */
454 	if ((ufsvfsp = ip->i_ufsvfs) == NULL) {
455 		error = EIO;
456 		goto out;
457 	}
458 	if (MANDLOCK(vp, ip->i_mode)) {
459 
460 		ASSERT(RW_WRITE_HELD(&ip->i_rwlock));
461 
462 		/*
463 		 * ufs_getattr ends up being called by chklock
464 		 */
465 		error = chklock(vp, FWRITE, uiop->uio_loffset,
466 		    uiop->uio_resid, uiop->uio_fmode, ct);
467 		if (error)
468 			goto out;
469 	}
470 
471 	/* i_rwlock can change in chklock */
472 	exclusive = rw_write_held(&ip->i_rwlock);
473 	rewriteflg = ufs_check_rewrite(ip, uiop, ioflag);
474 
475 	/*
476 	 * Check for fast-path special case of directio re-writes.
477 	 */
478 	if ((ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio) &&
479 	    !exclusive && rewriteflg) {
480 
481 		error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_WRITE_MASK);
482 		if (error)
483 			goto out;
484 
485 		rw_enter(&ip->i_contents, RW_READER);
486 		error = ufs_directio_write(ip, uiop, ioflag, 1, cr,
487 		    &directio_status);
488 		if (directio_status == DIRECTIO_SUCCESS) {
489 			uint_t i_flag_save;
490 
491 			if (start_resid != uiop->uio_resid)
492 				error = 0;
493 			/*
494 			 * Special treatment of access times for re-writes.
495 			 * If IMOD is not already set, then convert it
496 			 * to IMODACC for this operation. This defers
497 			 * entering a delta into the log until the inode
498 			 * is flushed. This mimics what is done for read
499 			 * operations and inode access time.
500 			 */
501 			mutex_enter(&ip->i_tlock);
502 			i_flag_save = ip->i_flag;
503 			ip->i_flag |= IUPD | ICHG;
504 			ip->i_seq++;
505 			ITIMES_NOLOCK(ip);
506 			if ((i_flag_save & IMOD) == 0) {
507 				ip->i_flag &= ~IMOD;
508 				ip->i_flag |= IMODACC;
509 			}
510 			mutex_exit(&ip->i_tlock);
511 			rw_exit(&ip->i_contents);
512 			if (ulp)
513 				ufs_lockfs_end(ulp);
514 			goto out;
515 		}
516 		rw_exit(&ip->i_contents);
517 		if (ulp)
518 			ufs_lockfs_end(ulp);
519 	}
520 
521 	if (!exclusive && !rw_tryupgrade(&ip->i_rwlock)) {
522 		rw_exit(&ip->i_rwlock);
523 		rw_enter(&ip->i_rwlock, RW_WRITER);
524 		/*
525 		 * Mandatory locking could have been enabled
526 		 * after dropping the i_rwlock.
527 		 */
528 		if (MANDLOCK(vp, ip->i_mode))
529 			goto retry_mandlock;
530 	}
531 
532 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_WRITE_MASK);
533 	if (error)
534 		goto out;
535 
536 	/*
537 	 * Amount of log space needed for this write
538 	 */
539 	if (!rewriteflg || !(ioflag & FDSYNC))
540 		TRANS_WRITE_RESV(ip, uiop, ulp, &resv, &resid);
541 
542 	/*
543 	 * Throttle writes.
544 	 */
545 	if (ufs_WRITES && (ip->i_writes > ufs_HW)) {
546 		mutex_enter(&ip->i_tlock);
547 		while (ip->i_writes > ufs_HW) {
548 			ufs_throttles++;
549 			cv_wait(&ip->i_wrcv, &ip->i_tlock);
550 		}
551 		mutex_exit(&ip->i_tlock);
552 	}
553 
554 	/*
555 	 * Enter Transaction
556 	 *
557 	 * If the write is a rewrite there is no need to open a transaction
558 	 * if the FDSYNC flag is set and not the FSYNC.  In this case just
559 	 * set the IMODACC flag to modify do the update at a later time
560 	 * thus avoiding the overhead of the logging transaction that is
561 	 * not required.
562 	 */
563 	if (ioflag & (FSYNC|FDSYNC)) {
564 		if (ulp) {
565 			if (rewriteflg) {
566 				uint_t i_flag_save;
567 
568 				rw_enter(&ip->i_contents, RW_READER);
569 				mutex_enter(&ip->i_tlock);
570 				i_flag_save = ip->i_flag;
571 				ip->i_flag |= IUPD | ICHG;
572 				ip->i_seq++;
573 				ITIMES_NOLOCK(ip);
574 				if ((i_flag_save & IMOD) == 0) {
575 					ip->i_flag &= ~IMOD;
576 					ip->i_flag |= IMODACC;
577 				}
578 				mutex_exit(&ip->i_tlock);
579 				rw_exit(&ip->i_contents);
580 			} else {
581 				int terr = 0;
582 				TRANS_BEGIN_SYNC(ufsvfsp, TOP_WRITE_SYNC, resv,
583 				    terr);
584 				ASSERT(!terr);
585 			}
586 		}
587 	} else {
588 		if (ulp)
589 			TRANS_BEGIN_ASYNC(ufsvfsp, TOP_WRITE, resv);
590 	}
591 
592 	/*
593 	 * Write the file
594 	 */
595 	rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
596 	rw_enter(&ip->i_contents, RW_WRITER);
597 	if ((ioflag & FAPPEND) != 0 && (ip->i_mode & IFMT) == IFREG) {
598 		/*
599 		 * In append mode start at end of file.
600 		 */
601 		uiop->uio_loffset = ip->i_size;
602 	}
603 
604 	/*
605 	 * Mild optimisation, don't call ufs_trans_write() unless we have to
606 	 * Also, suppress file system full messages if we will retry.
607 	 */
608 	if (retry)
609 		ip->i_flag |= IQUIET;
610 	if (resid) {
611 		TRANS_WRITE(ip, uiop, ioflag, error, ulp, cr, resv, resid);
612 	} else {
613 		error = wrip(ip, uiop, ioflag, cr);
614 	}
615 	ip->i_flag &= ~IQUIET;
616 
617 	rw_exit(&ip->i_contents);
618 	rw_exit(&ufsvfsp->vfs_dqrwlock);
619 
620 	/*
621 	 * Leave Transaction
622 	 */
623 	if (ulp) {
624 		if (ioflag & (FSYNC|FDSYNC)) {
625 			if (!rewriteflg) {
626 				int terr = 0;
627 
628 				TRANS_END_SYNC(ufsvfsp, terr, TOP_WRITE_SYNC,
629 				    resv);
630 				if (error == 0)
631 					error = terr;
632 			}
633 		} else {
634 			TRANS_END_ASYNC(ufsvfsp, TOP_WRITE, resv);
635 		}
636 		ufs_lockfs_end(ulp);
637 	}
638 out:
639 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
640 		/*
641 		 * Any blocks tied up in pending deletes?
642 		 */
643 		ufs_delete_drain_wait(ufsvfsp, 1);
644 		retry = 0;
645 		goto retry_mandlock;
646 	}
647 
648 	if (error == ENOSPC && (start_resid != uiop->uio_resid))
649 		error = 0;
650 
651 	return (error);
652 }
653 
654 /*
655  * Don't cache write blocks to files with the sticky bit set.
656  * Used to keep swap files from blowing the page cache on a server.
657  */
658 int stickyhack = 1;
659 
660 /*
661  * wrip does the real work of write requests for ufs.
662  */
663 int
664 wrip(struct inode *ip, struct uio *uio, int ioflag, struct cred *cr)
665 {
666 	rlim64_t limit = uio->uio_llimit;
667 	u_offset_t off;
668 	u_offset_t old_i_size;
669 	struct fs *fs;
670 	struct vnode *vp;
671 	struct ufsvfs *ufsvfsp;
672 	caddr_t base;
673 	long start_resid = uio->uio_resid;	/* save starting resid */
674 	long premove_resid;			/* resid before uiomove() */
675 	uint_t flags;
676 	int newpage;
677 	int iupdat_flag, directio_status;
678 	int n, on, mapon;
679 	int error, pagecreate;
680 	int do_dqrwlock;		/* drop/reacquire vfs_dqrwlock */
681 	int32_t	iblocks;
682 	int	new_iblocks;
683 
684 	/*
685 	 * ip->i_size is incremented before the uiomove
686 	 * is done on a write.  If the move fails (bad user
687 	 * address) reset ip->i_size.
688 	 * The better way would be to increment ip->i_size
689 	 * only if the uiomove succeeds.
690 	 */
691 	int i_size_changed = 0;
692 	o_mode_t type;
693 	int i_seq_needed = 0;
694 
695 	vp = ITOV(ip);
696 
697 	/*
698 	 * check for forced unmount - should not happen as
699 	 * the request passed the lockfs checks.
700 	 */
701 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
702 		return (EIO);
703 
704 	fs = ip->i_fs;
705 
706 	ASSERT(RW_WRITE_HELD(&ip->i_contents));
707 
708 	/* check for valid filetype */
709 	type = ip->i_mode & IFMT;
710 	if ((type != IFREG) && (type != IFDIR) && (type != IFATTRDIR) &&
711 	    (type != IFLNK) && (type != IFSHAD)) {
712 		return (EIO);
713 	}
714 
715 	/*
716 	 * the actual limit of UFS file size
717 	 * is UFS_MAXOFFSET_T
718 	 */
719 	if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T)
720 		limit = MAXOFFSET_T;
721 
722 	if (uio->uio_loffset >= limit) {
723 		proc_t *p = ttoproc(curthread);
724 
725 		mutex_enter(&p->p_lock);
726 		(void) rctl_action(rctlproc_legacy[RLIMIT_FSIZE], p->p_rctls,
727 		    p, RCA_UNSAFE_SIGINFO);
728 		mutex_exit(&p->p_lock);
729 		return (EFBIG);
730 	}
731 
732 	/*
733 	 * if largefiles are disallowed, the limit is
734 	 * the pre-largefiles value of 2GB
735 	 */
736 	if (ufsvfsp->vfs_lfflags & UFS_LARGEFILES)
737 		limit = MIN(UFS_MAXOFFSET_T, limit);
738 	else
739 		limit = MIN(MAXOFF32_T, limit);
740 
741 	if (uio->uio_loffset < (offset_t)0) {
742 		return (EINVAL);
743 	}
744 	if (uio->uio_resid == 0) {
745 		return (0);
746 	}
747 
748 	if (uio->uio_loffset >= limit)
749 		return (EFBIG);
750 
751 	ip->i_flag |= INOACC;	/* don't update ref time in getpage */
752 
753 	if (ioflag & (FSYNC|FDSYNC)) {
754 		ip->i_flag |= ISYNC;
755 		iupdat_flag = 1;
756 	}
757 	/*
758 	 * Try to go direct
759 	 */
760 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio) {
761 		uio->uio_llimit = limit;
762 		error = ufs_directio_write(ip, uio, ioflag, 0, cr,
763 		    &directio_status);
764 		/*
765 		 * If ufs_directio wrote to the file or set the flags,
766 		 * we need to update i_seq, but it may be deferred.
767 		 */
768 		if (start_resid != uio->uio_resid ||
769 		    (ip->i_flag & (ICHG|IUPD))) {
770 			i_seq_needed = 1;
771 			ip->i_flag |= ISEQ;
772 		}
773 		if (directio_status == DIRECTIO_SUCCESS)
774 			goto out;
775 	}
776 
777 	/*
778 	 * Behavior with respect to dropping/reacquiring vfs_dqrwlock:
779 	 *
780 	 * o shadow inodes: vfs_dqrwlock is not held at all
781 	 * o quota updates: vfs_dqrwlock is read or write held
782 	 * o other updates: vfs_dqrwlock is read held
783 	 *
784 	 * The first case is the only one where we do not hold
785 	 * vfs_dqrwlock at all while entering wrip().
786 	 * We must make sure not to downgrade/drop vfs_dqrwlock if we
787 	 * have it as writer, i.e. if we are updating the quota inode.
788 	 * There is no potential deadlock scenario in this case as
789 	 * ufs_getpage() takes care of this and avoids reacquiring
790 	 * vfs_dqrwlock in that case.
791 	 *
792 	 * This check is done here since the above conditions do not change
793 	 * and we possibly loop below, so save a few cycles.
794 	 */
795 	if ((type == IFSHAD) ||
796 	    (rw_owner(&ufsvfsp->vfs_dqrwlock) == curthread)) {
797 		do_dqrwlock = 0;
798 	} else {
799 		do_dqrwlock = 1;
800 	}
801 
802 	/*
803 	 * Large Files: We cast MAXBMASK to offset_t
804 	 * inorder to mask out the higher bits. Since offset_t
805 	 * is a signed value, the high order bit set in MAXBMASK
806 	 * value makes it do the right thing by having all bits 1
807 	 * in the higher word. May be removed for _SOLARIS64_.
808 	 */
809 
810 	fs = ip->i_fs;
811 	do {
812 		u_offset_t uoff = uio->uio_loffset;
813 		off = uoff & (offset_t)MAXBMASK;
814 		mapon = (int)(uoff & (offset_t)MAXBOFFSET);
815 		on = (int)blkoff(fs, uoff);
816 		n = (int)MIN(fs->fs_bsize - on, uio->uio_resid);
817 		new_iblocks = 1;
818 
819 		if (type == IFREG && uoff + n >= limit) {
820 			if (uoff >= limit) {
821 				error = EFBIG;
822 				goto out;
823 			}
824 			/*
825 			 * since uoff + n >= limit,
826 			 * therefore n >= limit - uoff, and n is an int
827 			 * so it is safe to cast it to an int
828 			 */
829 			n = (int)(limit - (rlim64_t)uoff);
830 		}
831 		if (uoff + n > ip->i_size) {
832 			/*
833 			 * We are extending the length of the file.
834 			 * bmap is used so that we are sure that
835 			 * if we need to allocate new blocks, that it
836 			 * is done here before we up the file size.
837 			 */
838 			error = bmap_write(ip, uoff, (int)(on + n),
839 			    mapon == 0, NULL, cr);
840 			/*
841 			 * bmap_write never drops i_contents so if
842 			 * the flags are set it changed the file.
843 			 */
844 			if (ip->i_flag & (ICHG|IUPD)) {
845 				i_seq_needed = 1;
846 				ip->i_flag |= ISEQ;
847 			}
848 			if (error)
849 				break;
850 			/*
851 			 * There is a window of vulnerability here.
852 			 * The sequence of operations: allocate file
853 			 * system blocks, uiomove the data into pages,
854 			 * and then update the size of the file in the
855 			 * inode, must happen atomically.  However, due
856 			 * to current locking constraints, this can not
857 			 * be done.
858 			 */
859 			ASSERT(ip->i_writer == NULL);
860 			ip->i_writer = curthread;
861 			i_size_changed = 1;
862 			/*
863 			 * If we are writing from the beginning of
864 			 * the mapping, we can just create the
865 			 * pages without having to read them.
866 			 */
867 			pagecreate = (mapon == 0);
868 		} else if (n == MAXBSIZE) {
869 			/*
870 			 * Going to do a whole mappings worth,
871 			 * so we can just create the pages w/o
872 			 * having to read them in.  But before
873 			 * we do that, we need to make sure any
874 			 * needed blocks are allocated first.
875 			 */
876 			iblocks = ip->i_blocks;
877 			error = bmap_write(ip, uoff, (int)(on + n),
878 			    BI_ALLOC_ONLY, NULL, cr);
879 			/*
880 			 * bmap_write never drops i_contents so if
881 			 * the flags are set it changed the file.
882 			 */
883 			if (ip->i_flag & (ICHG|IUPD)) {
884 				i_seq_needed = 1;
885 				ip->i_flag |= ISEQ;
886 			}
887 			if (error)
888 				break;
889 			pagecreate = 1;
890 			/*
891 			 * check if the new created page needed the
892 			 * allocation of new disk blocks.
893 			 */
894 			if (iblocks == ip->i_blocks)
895 				new_iblocks = 0; /* no new blocks allocated */
896 		} else {
897 			pagecreate = 0;
898 			/*
899 			 * In sync mode flush the indirect blocks which
900 			 * may have been allocated and not written on
901 			 * disk. In above cases bmap_write will allocate
902 			 * in sync mode.
903 			 */
904 			if (ioflag & (FSYNC|FDSYNC)) {
905 				error = ufs_indirblk_sync(ip, uoff);
906 				if (error)
907 					break;
908 			}
909 		}
910 
911 		/*
912 		 * At this point we can enter ufs_getpage() in one
913 		 * of two ways:
914 		 * 1) segmap_getmapflt() calls ufs_getpage() when the
915 		 *    forcefault parameter is true (pagecreate == 0)
916 		 * 2) uiomove() causes a page fault.
917 		 *
918 		 * We have to drop the contents lock to prevent the VM
919 		 * system from trying to reacquire it in ufs_getpage()
920 		 * should the uiomove cause a pagefault.
921 		 *
922 		 * We have to drop the reader vfs_dqrwlock here as well.
923 		 */
924 		rw_exit(&ip->i_contents);
925 		if (do_dqrwlock) {
926 			ASSERT(RW_LOCK_HELD(&ufsvfsp->vfs_dqrwlock));
927 			ASSERT(!(RW_WRITE_HELD(&ufsvfsp->vfs_dqrwlock)));
928 			rw_exit(&ufsvfsp->vfs_dqrwlock);
929 		}
930 
931 		newpage = 0;
932 		premove_resid = uio->uio_resid;
933 
934 		/*
935 		 * Touch the page and fault it in if it is not in core
936 		 * before segmap_getmapflt or vpm_data_copy can lock it.
937 		 * This is to avoid the deadlock if the buffer is mapped
938 		 * to the same file through mmap which we want to write.
939 		 */
940 		uio_prefaultpages((long)n, uio);
941 
942 		if (vpm_enable) {
943 			/*
944 			 * Copy data. If new pages are created, part of
945 			 * the page that is not written will be initizliazed
946 			 * with zeros.
947 			 */
948 			error = vpm_data_copy(vp, (off + mapon), (uint_t)n,
949 			    uio, !pagecreate, &newpage, 0, S_WRITE);
950 		} else {
951 
952 			base = segmap_getmapflt(segkmap, vp, (off + mapon),
953 			    (uint_t)n, !pagecreate, S_WRITE);
954 
955 			/*
956 			 * segmap_pagecreate() returns 1 if it calls
957 			 * page_create_va() to allocate any pages.
958 			 */
959 
960 			if (pagecreate)
961 				newpage = segmap_pagecreate(segkmap, base,
962 				    (size_t)n, 0);
963 
964 			error = uiomove(base + mapon, (long)n, UIO_WRITE, uio);
965 		}
966 
967 		/*
968 		 * If "newpage" is set, then a new page was created and it
969 		 * does not contain valid data, so it needs to be initialized
970 		 * at this point.
971 		 * Otherwise the page contains old data, which was overwritten
972 		 * partially or as a whole in uiomove.
973 		 * If there is only one iovec structure within uio, then
974 		 * on error uiomove will not be able to update uio->uio_loffset
975 		 * and we would zero the whole page here!
976 		 *
977 		 * If uiomove fails because of an error, the old valid data
978 		 * is kept instead of filling the rest of the page with zero's.
979 		 */
980 		if (!vpm_enable && newpage &&
981 		    uio->uio_loffset < roundup(off + mapon + n, PAGESIZE)) {
982 			/*
983 			 * We created pages w/o initializing them completely,
984 			 * thus we need to zero the part that wasn't set up.
985 			 * This happens on most EOF write cases and if
986 			 * we had some sort of error during the uiomove.
987 			 */
988 			int nzero, nmoved;
989 
990 			nmoved = (int)(uio->uio_loffset - (off + mapon));
991 			ASSERT(nmoved >= 0 && nmoved <= n);
992 			nzero = roundup(on + n, PAGESIZE) - nmoved;
993 			ASSERT(nzero > 0 && mapon + nmoved + nzero <= MAXBSIZE);
994 			(void) kzero(base + mapon + nmoved, (uint_t)nzero);
995 		}
996 
997 		/*
998 		 * Unlock the pages allocated by page_create_va()
999 		 * in segmap_pagecreate()
1000 		 */
1001 		if (!vpm_enable && newpage)
1002 			segmap_pageunlock(segkmap, base, (size_t)n, S_WRITE);
1003 
1004 		/*
1005 		 * If the size of the file changed, then update the
1006 		 * size field in the inode now.  This can't be done
1007 		 * before the call to segmap_pageunlock or there is
1008 		 * a potential deadlock with callers to ufs_putpage().
1009 		 * They will be holding i_contents and trying to lock
1010 		 * a page, while this thread is holding a page locked
1011 		 * and trying to acquire i_contents.
1012 		 */
1013 		if (i_size_changed) {
1014 			rw_enter(&ip->i_contents, RW_WRITER);
1015 			old_i_size = ip->i_size;
1016 			UFS_SET_ISIZE(uoff + n, ip);
1017 			TRANS_INODE(ufsvfsp, ip);
1018 			/*
1019 			 * file has grown larger than 2GB. Set flag
1020 			 * in superblock to indicate this, if it
1021 			 * is not already set.
1022 			 */
1023 			if ((ip->i_size > MAXOFF32_T) &&
1024 			    !(fs->fs_flags & FSLARGEFILES)) {
1025 				ASSERT(ufsvfsp->vfs_lfflags & UFS_LARGEFILES);
1026 				mutex_enter(&ufsvfsp->vfs_lock);
1027 				fs->fs_flags |= FSLARGEFILES;
1028 				ufs_sbwrite(ufsvfsp);
1029 				mutex_exit(&ufsvfsp->vfs_lock);
1030 			}
1031 			mutex_enter(&ip->i_tlock);
1032 			ip->i_writer = NULL;
1033 			cv_broadcast(&ip->i_wrcv);
1034 			mutex_exit(&ip->i_tlock);
1035 			rw_exit(&ip->i_contents);
1036 		}
1037 
1038 		if (error) {
1039 			/*
1040 			 * If we failed on a write, we may have already
1041 			 * allocated file blocks as well as pages.  It's
1042 			 * hard to undo the block allocation, but we must
1043 			 * be sure to invalidate any pages that may have
1044 			 * been allocated.
1045 			 *
1046 			 * If the page was created without initialization
1047 			 * then we must check if it should be possible
1048 			 * to destroy the new page and to keep the old data
1049 			 * on the disk.
1050 			 *
1051 			 * It is possible to destroy the page without
1052 			 * having to write back its contents only when
1053 			 * - the size of the file keeps unchanged
1054 			 * - bmap_write() did not allocate new disk blocks
1055 			 *   it is possible to create big files using "seek" and
1056 			 *   write to the end of the file. A "write" to a
1057 			 *   position before the end of the file would not
1058 			 *   change the size of the file but it would allocate
1059 			 *   new disk blocks.
1060 			 * - uiomove intended to overwrite the whole page.
1061 			 * - a new page was created (newpage == 1).
1062 			 */
1063 
1064 			if (i_size_changed == 0 && new_iblocks == 0 &&
1065 			    newpage) {
1066 
1067 				/* unwind what uiomove eventually last did */
1068 				uio->uio_resid = premove_resid;
1069 
1070 				/*
1071 				 * destroy the page, do not write ambiguous
1072 				 * data to the disk.
1073 				 */
1074 				flags = SM_DESTROY;
1075 			} else {
1076 				/*
1077 				 * write the page back to the disk, if dirty,
1078 				 * and remove the page from the cache.
1079 				 */
1080 				flags = SM_INVAL;
1081 			}
1082 
1083 			if (vpm_enable) {
1084 				/*
1085 				 *  Flush pages.
1086 				 */
1087 				(void) vpm_sync_pages(vp, off, n, flags);
1088 			} else {
1089 				(void) segmap_release(segkmap, base, flags);
1090 			}
1091 		} else {
1092 			flags = 0;
1093 			/*
1094 			 * Force write back for synchronous write cases.
1095 			 */
1096 			if ((ioflag & (FSYNC|FDSYNC)) || type == IFDIR) {
1097 				/*
1098 				 * If the sticky bit is set but the
1099 				 * execute bit is not set, we do a
1100 				 * synchronous write back and free
1101 				 * the page when done.  We set up swap
1102 				 * files to be handled this way to
1103 				 * prevent servers from keeping around
1104 				 * the client's swap pages too long.
1105 				 * XXX - there ought to be a better way.
1106 				 */
1107 				if (IS_SWAPVP(vp)) {
1108 					flags = SM_WRITE | SM_FREE |
1109 					    SM_DONTNEED;
1110 					iupdat_flag = 0;
1111 				} else {
1112 					flags = SM_WRITE;
1113 				}
1114 			} else if (n + on == MAXBSIZE || IS_SWAPVP(vp)) {
1115 				/*
1116 				 * Have written a whole block.
1117 				 * Start an asynchronous write and
1118 				 * mark the buffer to indicate that
1119 				 * it won't be needed again soon.
1120 				 */
1121 				flags = SM_WRITE | SM_ASYNC | SM_DONTNEED;
1122 			}
1123 			if (vpm_enable) {
1124 				/*
1125 				 * Flush pages.
1126 				 */
1127 				error = vpm_sync_pages(vp, off, n, flags);
1128 			} else {
1129 				error = segmap_release(segkmap, base, flags);
1130 			}
1131 			/*
1132 			 * If the operation failed and is synchronous,
1133 			 * then we need to unwind what uiomove() last
1134 			 * did so we can potentially return an error to
1135 			 * the caller.  If this write operation was
1136 			 * done in two pieces and the first succeeded,
1137 			 * then we won't return an error for the second
1138 			 * piece that failed.  However, we only want to
1139 			 * return a resid value that reflects what was
1140 			 * really done.
1141 			 *
1142 			 * Failures for non-synchronous operations can
1143 			 * be ignored since the page subsystem will
1144 			 * retry the operation until it succeeds or the
1145 			 * file system is unmounted.
1146 			 */
1147 			if (error) {
1148 				if ((ioflag & (FSYNC | FDSYNC)) ||
1149 				    type == IFDIR) {
1150 					uio->uio_resid = premove_resid;
1151 				} else {
1152 					error = 0;
1153 				}
1154 			}
1155 		}
1156 
1157 		/*
1158 		 * Re-acquire contents lock.
1159 		 * If it was dropped, reacquire reader vfs_dqrwlock as well.
1160 		 */
1161 		if (do_dqrwlock)
1162 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
1163 		rw_enter(&ip->i_contents, RW_WRITER);
1164 
1165 		/*
1166 		 * If the uiomove() failed or if a synchronous
1167 		 * page push failed, fix up i_size.
1168 		 */
1169 		if (error) {
1170 			if (i_size_changed) {
1171 				/*
1172 				 * The uiomove failed, and we
1173 				 * allocated blocks,so get rid
1174 				 * of them.
1175 				 */
1176 				(void) ufs_itrunc(ip, old_i_size, 0, cr);
1177 			}
1178 		} else {
1179 			/*
1180 			 * XXX - Can this be out of the loop?
1181 			 */
1182 			ip->i_flag |= IUPD | ICHG;
1183 			/*
1184 			 * Only do one increase of i_seq for multiple
1185 			 * pieces.  Because we drop locks, record
1186 			 * the fact that we changed the timestamp and
1187 			 * are deferring the increase in case another thread
1188 			 * pushes our timestamp update.
1189 			 */
1190 			i_seq_needed = 1;
1191 			ip->i_flag |= ISEQ;
1192 			if (i_size_changed)
1193 				ip->i_flag |= IATTCHG;
1194 			if ((ip->i_mode & (IEXEC | (IEXEC >> 3) |
1195 			    (IEXEC >> 6))) != 0 &&
1196 			    (ip->i_mode & (ISUID | ISGID)) != 0 &&
1197 			    secpolicy_vnode_setid_retain(cr,
1198 			    (ip->i_mode & ISUID) != 0 && ip->i_uid == 0) != 0) {
1199 				/*
1200 				 * Clear Set-UID & Set-GID bits on
1201 				 * successful write if not privileged
1202 				 * and at least one of the execute bits
1203 				 * is set.  If we always clear Set-GID,
1204 				 * mandatory file and record locking is
1205 				 * unuseable.
1206 				 */
1207 				ip->i_mode &= ~(ISUID | ISGID);
1208 			}
1209 		}
1210 		/*
1211 		 * In the case the FDSYNC flag is set and this is a
1212 		 * "rewrite" we won't log a delta.
1213 		 * The FSYNC flag overrides all cases.
1214 		 */
1215 		if (!ufs_check_rewrite(ip, uio, ioflag) || !(ioflag & FDSYNC)) {
1216 			TRANS_INODE(ufsvfsp, ip);
1217 		}
1218 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
1219 
1220 out:
1221 	/*
1222 	 * Make sure i_seq is increased at least once per write
1223 	 */
1224 	if (i_seq_needed) {
1225 		ip->i_seq++;
1226 		ip->i_flag &= ~ISEQ;	/* no longer deferred */
1227 	}
1228 
1229 	/*
1230 	 * Inode is updated according to this table -
1231 	 *
1232 	 *   FSYNC	  FDSYNC(posix.4)
1233 	 *   --------------------------
1234 	 *   always@	  IATTCHG|IBDWRITE
1235 	 *
1236 	 * @ -	If we are doing synchronous write the only time we should
1237 	 *	not be sync'ing the ip here is if we have the stickyhack
1238 	 *	activated, the file is marked with the sticky bit and
1239 	 *	no exec bit, the file length has not been changed and
1240 	 *	no new blocks have been allocated during this write.
1241 	 */
1242 
1243 	if ((ip->i_flag & ISYNC) != 0) {
1244 		/*
1245 		 * we have eliminated nosync
1246 		 */
1247 		if ((ip->i_flag & (IATTCHG|IBDWRITE)) ||
1248 		    ((ioflag & FSYNC) && iupdat_flag)) {
1249 			ufs_iupdat(ip, 1);
1250 		}
1251 	}
1252 
1253 	/*
1254 	 * If we've already done a partial-write, terminate
1255 	 * the write but return no error unless the error is ENOSPC
1256 	 * because the caller can detect this and free resources and
1257 	 * try again.
1258 	 */
1259 	if ((start_resid != uio->uio_resid) && (error != ENOSPC))
1260 		error = 0;
1261 
1262 	ip->i_flag &= ~(INOACC | ISYNC);
1263 	ITIMES_NOLOCK(ip);
1264 	return (error);
1265 }
1266 
1267 /*
1268  * rdip does the real work of read requests for ufs.
1269  */
1270 int
1271 rdip(struct inode *ip, struct uio *uio, int ioflag, cred_t *cr)
1272 {
1273 	u_offset_t off;
1274 	caddr_t base;
1275 	struct fs *fs;
1276 	struct ufsvfs *ufsvfsp;
1277 	struct vnode *vp;
1278 	long oresid = uio->uio_resid;
1279 	u_offset_t n, on, mapon;
1280 	int error = 0;
1281 	int doupdate = 1;
1282 	uint_t flags;
1283 	int directio_status;
1284 	krw_t rwtype;
1285 	o_mode_t type;
1286 
1287 	vp = ITOV(ip);
1288 
1289 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
1290 
1291 	ufsvfsp = ip->i_ufsvfs;
1292 
1293 	if (ufsvfsp == NULL)
1294 		return (EIO);
1295 
1296 	fs = ufsvfsp->vfs_fs;
1297 
1298 	/* check for valid filetype */
1299 	type = ip->i_mode & IFMT;
1300 	if ((type != IFREG) && (type != IFDIR) && (type != IFATTRDIR) &&
1301 	    (type != IFLNK) && (type != IFSHAD)) {
1302 		return (EIO);
1303 	}
1304 
1305 	if (uio->uio_loffset > UFS_MAXOFFSET_T) {
1306 		error = 0;
1307 		goto out;
1308 	}
1309 	if (uio->uio_loffset < (offset_t)0) {
1310 		return (EINVAL);
1311 	}
1312 	if (uio->uio_resid == 0) {
1313 		return (0);
1314 	}
1315 
1316 	if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) && (fs->fs_ronly == 0) &&
1317 	    (!ufsvfsp->vfs_noatime)) {
1318 		mutex_enter(&ip->i_tlock);
1319 		ip->i_flag |= IACC;
1320 		mutex_exit(&ip->i_tlock);
1321 	}
1322 	/*
1323 	 * Try to go direct
1324 	 */
1325 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio) {
1326 		error = ufs_directio_read(ip, uio, cr, &directio_status);
1327 		if (directio_status == DIRECTIO_SUCCESS)
1328 			goto out;
1329 	}
1330 
1331 	rwtype = (rw_write_held(&ip->i_contents)?RW_WRITER:RW_READER);
1332 
1333 	do {
1334 		offset_t diff;
1335 		u_offset_t uoff = uio->uio_loffset;
1336 		off = uoff & (offset_t)MAXBMASK;
1337 		mapon = (u_offset_t)(uoff & (offset_t)MAXBOFFSET);
1338 		on = (u_offset_t)blkoff(fs, uoff);
1339 		n = MIN((u_offset_t)fs->fs_bsize - on,
1340 		    (u_offset_t)uio->uio_resid);
1341 
1342 		diff = ip->i_size - uoff;
1343 
1344 		if (diff <= (offset_t)0) {
1345 			error = 0;
1346 			goto out;
1347 		}
1348 		if (diff < (offset_t)n)
1349 			n = (int)diff;
1350 
1351 		/*
1352 		 * At this point we can enter ufs_getpage() in one of two
1353 		 * ways:
1354 		 * 1) segmap_getmapflt() calls ufs_getpage() when the
1355 		 *    forcefault parameter is true (value of 1 is passed)
1356 		 * 2) uiomove() causes a page fault.
1357 		 *
1358 		 * We cannot hold onto an i_contents reader lock without
1359 		 * risking deadlock in ufs_getpage() so drop a reader lock.
1360 		 * The ufs_getpage() dolock logic already allows for a
1361 		 * thread holding i_contents as writer to work properly
1362 		 * so we keep a writer lock.
1363 		 */
1364 		if (rwtype == RW_READER)
1365 			rw_exit(&ip->i_contents);
1366 
1367 		if (vpm_enable) {
1368 			/*
1369 			 * Copy data.
1370 			 */
1371 			error = vpm_data_copy(vp, (off + mapon), (uint_t)n,
1372 			    uio, 1, NULL, 0, S_READ);
1373 		} else {
1374 			base = segmap_getmapflt(segkmap, vp, (off + mapon),
1375 			    (uint_t)n, 1, S_READ);
1376 			error = uiomove(base + mapon, (long)n, UIO_READ, uio);
1377 		}
1378 
1379 		flags = 0;
1380 		if (!error) {
1381 			/*
1382 			 * In POSIX SYNC (FSYNC and FDSYNC) read mode,
1383 			 * we want to make sure that the page which has
1384 			 * been read, is written on disk if it is dirty.
1385 			 * And corresponding indirect blocks should also
1386 			 * be flushed out.
1387 			 */
1388 			if ((ioflag & FRSYNC) && (ioflag & (FSYNC|FDSYNC))) {
1389 				flags |= SM_WRITE;
1390 			}
1391 			if (vpm_enable) {
1392 				error = vpm_sync_pages(vp, off, n, flags);
1393 			} else {
1394 				error = segmap_release(segkmap, base, flags);
1395 			}
1396 		} else {
1397 			if (vpm_enable) {
1398 				(void) vpm_sync_pages(vp, off, n, flags);
1399 			} else {
1400 				(void) segmap_release(segkmap, base, flags);
1401 			}
1402 		}
1403 
1404 		if (rwtype == RW_READER)
1405 			rw_enter(&ip->i_contents, rwtype);
1406 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
1407 out:
1408 	/*
1409 	 * Inode is updated according to this table if FRSYNC is set.
1410 	 *
1411 	 *   FSYNC	  FDSYNC(posix.4)
1412 	 *   --------------------------
1413 	 *   always	  IATTCHG|IBDWRITE
1414 	 */
1415 	/*
1416 	 * The inode is not updated if we're logging and the inode is a
1417 	 * directory with FRSYNC, FSYNC and FDSYNC flags set.
1418 	 */
1419 	if (ioflag & FRSYNC) {
1420 		if (TRANS_ISTRANS(ufsvfsp) && ((ip->i_mode & IFMT) == IFDIR)) {
1421 			doupdate = 0;
1422 		}
1423 		if (doupdate) {
1424 			if ((ioflag & FSYNC) ||
1425 			    ((ioflag & FDSYNC) &&
1426 			    (ip->i_flag & (IATTCHG|IBDWRITE)))) {
1427 				ufs_iupdat(ip, 1);
1428 			}
1429 		}
1430 	}
1431 	/*
1432 	 * If we've already done a partial read, terminate
1433 	 * the read but return no error.
1434 	 */
1435 	if (oresid != uio->uio_resid)
1436 		error = 0;
1437 	ITIMES(ip);
1438 
1439 	return (error);
1440 }
1441 
1442 /* ARGSUSED */
1443 static int
1444 ufs_ioctl(
1445 	struct vnode	*vp,
1446 	int		cmd,
1447 	intptr_t	arg,
1448 	int		flag,
1449 	struct cred	*cr,
1450 	int		*rvalp,
1451 	caller_context_t *ct)
1452 {
1453 	struct lockfs	lockfs, lockfs_out;
1454 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
1455 	char		*comment, *original_comment;
1456 	struct fs	*fs;
1457 	struct ulockfs	*ulp;
1458 	offset_t	off;
1459 	extern int	maxphys;
1460 	int		error;
1461 	int		issync;
1462 	int		trans_size;
1463 
1464 
1465 	/*
1466 	 * forcibly unmounted
1467 	 */
1468 	if (ufsvfsp == NULL || vp->v_vfsp == NULL ||
1469 	    vp->v_vfsp->vfs_flag & VFS_UNMOUNTED)
1470 		return (EIO);
1471 	fs = ufsvfsp->vfs_fs;
1472 
1473 	if (cmd == Q_QUOTACTL) {
1474 		error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_QUOTA_MASK);
1475 		if (error)
1476 			return (error);
1477 
1478 		if (ulp) {
1479 			TRANS_BEGIN_ASYNC(ufsvfsp, TOP_QUOTA,
1480 			    TOP_SETQUOTA_SIZE(fs));
1481 		}
1482 
1483 		error = quotactl(vp, arg, flag, cr);
1484 
1485 		if (ulp) {
1486 			TRANS_END_ASYNC(ufsvfsp, TOP_QUOTA,
1487 			    TOP_SETQUOTA_SIZE(fs));
1488 			ufs_lockfs_end(ulp);
1489 		}
1490 		return (error);
1491 	}
1492 
1493 	switch (cmd) {
1494 		case _FIOLFS:
1495 			/*
1496 			 * file system locking
1497 			 */
1498 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1499 				return (EPERM);
1500 
1501 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1502 				if (copyin((caddr_t)arg, &lockfs,
1503 				    sizeof (struct lockfs)))
1504 					return (EFAULT);
1505 			}
1506 #ifdef _SYSCALL32_IMPL
1507 			else {
1508 				struct lockfs32	lockfs32;
1509 				/* Translate ILP32 lockfs to LP64 lockfs */
1510 				if (copyin((caddr_t)arg, &lockfs32,
1511 				    sizeof (struct lockfs32)))
1512 					return (EFAULT);
1513 				lockfs.lf_lock = (ulong_t)lockfs32.lf_lock;
1514 				lockfs.lf_flags = (ulong_t)lockfs32.lf_flags;
1515 				lockfs.lf_key = (ulong_t)lockfs32.lf_key;
1516 				lockfs.lf_comlen = (ulong_t)lockfs32.lf_comlen;
1517 				lockfs.lf_comment =
1518 				    (caddr_t)(uintptr_t)lockfs32.lf_comment;
1519 			}
1520 #endif /* _SYSCALL32_IMPL */
1521 
1522 			if (lockfs.lf_comlen) {
1523 				if (lockfs.lf_comlen > LOCKFS_MAXCOMMENTLEN)
1524 					return (ENAMETOOLONG);
1525 				comment =
1526 				    kmem_alloc(lockfs.lf_comlen, KM_SLEEP);
1527 				if (copyin(lockfs.lf_comment, comment,
1528 				    lockfs.lf_comlen)) {
1529 					kmem_free(comment, lockfs.lf_comlen);
1530 					return (EFAULT);
1531 				}
1532 				original_comment = lockfs.lf_comment;
1533 				lockfs.lf_comment = comment;
1534 			}
1535 			if ((error = ufs_fiolfs(vp, &lockfs, 0)) == 0) {
1536 				lockfs.lf_comment = original_comment;
1537 
1538 				if ((flag & DATAMODEL_MASK) ==
1539 				    DATAMODEL_NATIVE) {
1540 					(void) copyout(&lockfs, (caddr_t)arg,
1541 					    sizeof (struct lockfs));
1542 				}
1543 #ifdef _SYSCALL32_IMPL
1544 				else {
1545 					struct lockfs32	lockfs32;
1546 					/* Translate LP64 to ILP32 lockfs */
1547 					lockfs32.lf_lock =
1548 					    (uint32_t)lockfs.lf_lock;
1549 					lockfs32.lf_flags =
1550 					    (uint32_t)lockfs.lf_flags;
1551 					lockfs32.lf_key =
1552 					    (uint32_t)lockfs.lf_key;
1553 					lockfs32.lf_comlen =
1554 					    (uint32_t)lockfs.lf_comlen;
1555 					lockfs32.lf_comment =
1556 					    (uint32_t)(uintptr_t)
1557 					    lockfs.lf_comment;
1558 					(void) copyout(&lockfs32, (caddr_t)arg,
1559 					    sizeof (struct lockfs32));
1560 				}
1561 #endif /* _SYSCALL32_IMPL */
1562 
1563 			} else {
1564 				if (lockfs.lf_comlen)
1565 					kmem_free(comment, lockfs.lf_comlen);
1566 			}
1567 			return (error);
1568 
1569 		case _FIOLFSS:
1570 			/*
1571 			 * get file system locking status
1572 			 */
1573 
1574 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1575 				if (copyin((caddr_t)arg, &lockfs,
1576 				    sizeof (struct lockfs)))
1577 					return (EFAULT);
1578 			}
1579 #ifdef _SYSCALL32_IMPL
1580 			else {
1581 				struct lockfs32	lockfs32;
1582 				/* Translate ILP32 lockfs to LP64 lockfs */
1583 				if (copyin((caddr_t)arg, &lockfs32,
1584 				    sizeof (struct lockfs32)))
1585 					return (EFAULT);
1586 				lockfs.lf_lock = (ulong_t)lockfs32.lf_lock;
1587 				lockfs.lf_flags = (ulong_t)lockfs32.lf_flags;
1588 				lockfs.lf_key = (ulong_t)lockfs32.lf_key;
1589 				lockfs.lf_comlen = (ulong_t)lockfs32.lf_comlen;
1590 				lockfs.lf_comment =
1591 				    (caddr_t)(uintptr_t)lockfs32.lf_comment;
1592 			}
1593 #endif /* _SYSCALL32_IMPL */
1594 
1595 			if (error =  ufs_fiolfss(vp, &lockfs_out))
1596 				return (error);
1597 			lockfs.lf_lock = lockfs_out.lf_lock;
1598 			lockfs.lf_key = lockfs_out.lf_key;
1599 			lockfs.lf_flags = lockfs_out.lf_flags;
1600 			lockfs.lf_comlen = MIN(lockfs.lf_comlen,
1601 			    lockfs_out.lf_comlen);
1602 
1603 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1604 				if (copyout(&lockfs, (caddr_t)arg,
1605 				    sizeof (struct lockfs)))
1606 					return (EFAULT);
1607 			}
1608 #ifdef _SYSCALL32_IMPL
1609 			else {
1610 				/* Translate LP64 to ILP32 lockfs */
1611 				struct lockfs32	lockfs32;
1612 				lockfs32.lf_lock = (uint32_t)lockfs.lf_lock;
1613 				lockfs32.lf_flags = (uint32_t)lockfs.lf_flags;
1614 				lockfs32.lf_key = (uint32_t)lockfs.lf_key;
1615 				lockfs32.lf_comlen = (uint32_t)lockfs.lf_comlen;
1616 				lockfs32.lf_comment =
1617 				    (uint32_t)(uintptr_t)lockfs.lf_comment;
1618 				if (copyout(&lockfs32, (caddr_t)arg,
1619 				    sizeof (struct lockfs32)))
1620 					return (EFAULT);
1621 			}
1622 #endif /* _SYSCALL32_IMPL */
1623 
1624 			if (lockfs.lf_comlen &&
1625 			    lockfs.lf_comment && lockfs_out.lf_comment)
1626 				if (copyout(lockfs_out.lf_comment,
1627 				    lockfs.lf_comment, lockfs.lf_comlen))
1628 					return (EFAULT);
1629 			return (0);
1630 
1631 		case _FIOSATIME:
1632 			/*
1633 			 * set access time
1634 			 */
1635 
1636 			/*
1637 			 * if mounted w/o atime, return quietly.
1638 			 * I briefly thought about returning ENOSYS, but
1639 			 * figured that most apps would consider this fatal
1640 			 * but the idea is to make this as seamless as poss.
1641 			 */
1642 			if (ufsvfsp->vfs_noatime)
1643 				return (0);
1644 
1645 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1646 			    ULOCKFS_SETATTR_MASK);
1647 			if (error)
1648 				return (error);
1649 
1650 			if (ulp) {
1651 				trans_size = (int)TOP_SETATTR_SIZE(VTOI(vp));
1652 				TRANS_BEGIN_CSYNC(ufsvfsp, issync,
1653 				    TOP_SETATTR, trans_size);
1654 			}
1655 
1656 			error = ufs_fiosatime(vp, (struct timeval *)arg,
1657 			    flag, cr);
1658 
1659 			if (ulp) {
1660 				TRANS_END_CSYNC(ufsvfsp, error, issync,
1661 				    TOP_SETATTR, trans_size);
1662 				ufs_lockfs_end(ulp);
1663 			}
1664 			return (error);
1665 
1666 		case _FIOSDIO:
1667 			/*
1668 			 * set delayed-io
1669 			 */
1670 			return (ufs_fiosdio(vp, (uint_t *)arg, flag, cr));
1671 
1672 		case _FIOGDIO:
1673 			/*
1674 			 * get delayed-io
1675 			 */
1676 			return (ufs_fiogdio(vp, (uint_t *)arg, flag, cr));
1677 
1678 		case _FIOIO:
1679 			/*
1680 			 * inode open
1681 			 */
1682 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1683 			    ULOCKFS_VGET_MASK);
1684 			if (error)
1685 				return (error);
1686 
1687 			error = ufs_fioio(vp, (struct fioio *)arg, flag, cr);
1688 
1689 			if (ulp) {
1690 				ufs_lockfs_end(ulp);
1691 			}
1692 			return (error);
1693 
1694 		case _FIOFFS:
1695 			/*
1696 			 * file system flush (push w/invalidate)
1697 			 */
1698 			if ((caddr_t)arg != NULL)
1699 				return (EINVAL);
1700 			return (ufs_fioffs(vp, NULL, cr));
1701 
1702 		case _FIOISBUSY:
1703 			/*
1704 			 * Contract-private interface for Legato
1705 			 * Purge this vnode from the DNLC and decide
1706 			 * if this vnode is busy (*arg == 1) or not
1707 			 * (*arg == 0)
1708 			 */
1709 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1710 				return (EPERM);
1711 			error = ufs_fioisbusy(vp, (int *)arg, cr);
1712 			return (error);
1713 
1714 		case _FIODIRECTIO:
1715 			return (ufs_fiodirectio(vp, (int)arg, cr));
1716 
1717 		case _FIOTUNE:
1718 			/*
1719 			 * Tune the file system (aka setting fs attributes)
1720 			 */
1721 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1722 			    ULOCKFS_SETATTR_MASK);
1723 			if (error)
1724 				return (error);
1725 
1726 			error = ufs_fiotune(vp, (struct fiotune *)arg, cr);
1727 
1728 			if (ulp)
1729 				ufs_lockfs_end(ulp);
1730 			return (error);
1731 
1732 		case _FIOLOGENABLE:
1733 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1734 				return (EPERM);
1735 			return (ufs_fiologenable(vp, (void *)arg, cr, flag));
1736 
1737 		case _FIOLOGDISABLE:
1738 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1739 				return (EPERM);
1740 			return (ufs_fiologdisable(vp, (void *)arg, cr, flag));
1741 
1742 		case _FIOISLOG:
1743 			return (ufs_fioislog(vp, (void *)arg, cr, flag));
1744 
1745 		case _FIOSNAPSHOTCREATE_MULTI:
1746 		{
1747 			struct fiosnapcreate_multi	fc, *fcp;
1748 			size_t	fcm_size;
1749 
1750 			if (copyin((void *)arg, &fc, sizeof (fc)))
1751 				return (EFAULT);
1752 			if (fc.backfilecount > MAX_BACKFILE_COUNT)
1753 				return (EINVAL);
1754 			fcm_size = sizeof (struct fiosnapcreate_multi) +
1755 			    (fc.backfilecount - 1) * sizeof (int);
1756 			fcp = (struct fiosnapcreate_multi *)
1757 			    kmem_alloc(fcm_size, KM_SLEEP);
1758 			if (copyin((void *)arg, fcp, fcm_size)) {
1759 				kmem_free(fcp, fcm_size);
1760 				return (EFAULT);
1761 			}
1762 			error = ufs_snap_create(vp, fcp, cr);
1763 			/*
1764 			 * Do copyout even if there is an error because
1765 			 * the details of error is stored in fcp.
1766 			 */
1767 			if (copyout(fcp, (void *)arg, fcm_size))
1768 				error = EFAULT;
1769 			kmem_free(fcp, fcm_size);
1770 			return (error);
1771 		}
1772 
1773 		case _FIOSNAPSHOTDELETE:
1774 		{
1775 			struct fiosnapdelete	fc;
1776 
1777 			if (copyin((void *)arg, &fc, sizeof (fc)))
1778 				return (EFAULT);
1779 			error = ufs_snap_delete(vp, &fc, cr);
1780 			if (!error && copyout(&fc, (void *)arg, sizeof (fc)))
1781 				error = EFAULT;
1782 			return (error);
1783 		}
1784 
1785 		case _FIOGETSUPERBLOCK:
1786 			if (copyout(fs, (void *)arg, SBSIZE))
1787 				return (EFAULT);
1788 			return (0);
1789 
1790 		case _FIOGETMAXPHYS:
1791 			if (copyout(&maxphys, (void *)arg, sizeof (maxphys)))
1792 				return (EFAULT);
1793 			return (0);
1794 
1795 		/*
1796 		 * The following 3 ioctls are for TSufs support
1797 		 * although could potentially be used elsewhere
1798 		 */
1799 		case _FIO_SET_LUFS_DEBUG:
1800 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1801 				return (EPERM);
1802 			lufs_debug = (uint32_t)arg;
1803 			return (0);
1804 
1805 		case _FIO_SET_LUFS_ERROR:
1806 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1807 				return (EPERM);
1808 			TRANS_SETERROR(ufsvfsp);
1809 			return (0);
1810 
1811 		case _FIO_GET_TOP_STATS:
1812 		{
1813 			fio_lufs_stats_t *ls;
1814 			ml_unit_t *ul = ufsvfsp->vfs_log;
1815 
1816 			ls = kmem_zalloc(sizeof (*ls), KM_SLEEP);
1817 			ls->ls_debug = ul->un_debug; /* return debug value */
1818 			/* Copy stucture if statistics are being kept */
1819 			if (ul->un_logmap->mtm_tops) {
1820 				ls->ls_topstats = *(ul->un_logmap->mtm_tops);
1821 			}
1822 			error = 0;
1823 			if (copyout(ls, (void *)arg, sizeof (*ls)))
1824 				error = EFAULT;
1825 			kmem_free(ls, sizeof (*ls));
1826 			return (error);
1827 		}
1828 
1829 		case _FIO_SEEK_DATA:
1830 		case _FIO_SEEK_HOLE:
1831 			if (ddi_copyin((void *)arg, &off, sizeof (off), flag))
1832 				return (EFAULT);
1833 			/* offset paramater is in/out */
1834 			error = ufs_fio_holey(vp, cmd, &off);
1835 			if (error)
1836 				return (error);
1837 			if (ddi_copyout(&off, (void *)arg, sizeof (off), flag))
1838 				return (EFAULT);
1839 			return (0);
1840 
1841 		case _FIO_COMPRESSED:
1842 		{
1843 			/*
1844 			 * This is a project private ufs ioctl() to mark
1845 			 * the inode as that belonging to a compressed
1846 			 * file. This is used to mark individual
1847 			 * compressed files in a miniroot archive.
1848 			 * The files compressed in this manner are
1849 			 * automatically decompressed by the dcfs filesystem
1850 			 * (via an interception in ufs_lookup - see decompvp())
1851 			 * which is layered on top of ufs on a system running
1852 			 * from the archive. See uts/common/fs/dcfs for details.
1853 			 * This ioctl only marks the file as compressed - the
1854 			 * actual compression is done by fiocompress (a
1855 			 * userland utility) which invokes this ioctl().
1856 			 */
1857 			struct inode *ip = VTOI(vp);
1858 
1859 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1860 			    ULOCKFS_SETATTR_MASK);
1861 			if (error)
1862 				return (error);
1863 
1864 			if (ulp) {
1865 				TRANS_BEGIN_ASYNC(ufsvfsp, TOP_IUPDAT,
1866 				    TOP_IUPDAT_SIZE(ip));
1867 			}
1868 
1869 			error = ufs_mark_compressed(vp);
1870 
1871 			if (ulp) {
1872 				TRANS_END_ASYNC(ufsvfsp, TOP_IUPDAT,
1873 				    TOP_IUPDAT_SIZE(ip));
1874 				ufs_lockfs_end(ulp);
1875 			}
1876 
1877 			return (error);
1878 
1879 		}
1880 
1881 		default:
1882 			return (ENOTTY);
1883 	}
1884 }
1885 
1886 
1887 /* ARGSUSED */
1888 static int
1889 ufs_getattr(struct vnode *vp, struct vattr *vap, int flags,
1890     struct cred *cr, caller_context_t *ct)
1891 {
1892 	struct inode *ip = VTOI(vp);
1893 	struct ufsvfs *ufsvfsp;
1894 	int err;
1895 
1896 	if (vap->va_mask == AT_SIZE) {
1897 		/*
1898 		 * for performance, if only the size is requested don't bother
1899 		 * with anything else.
1900 		 */
1901 		UFS_GET_ISIZE(&vap->va_size, ip);
1902 		return (0);
1903 	}
1904 
1905 	/*
1906 	 * inlined lockfs checks
1907 	 */
1908 	ufsvfsp = ip->i_ufsvfs;
1909 	if ((ufsvfsp == NULL) || ULOCKFS_IS_HLOCK(&ufsvfsp->vfs_ulockfs)) {
1910 		err = EIO;
1911 		goto out;
1912 	}
1913 
1914 	rw_enter(&ip->i_contents, RW_READER);
1915 	/*
1916 	 * Return all the attributes.  This should be refined so
1917 	 * that it only returns what's asked for.
1918 	 */
1919 
1920 	/*
1921 	 * Copy from inode table.
1922 	 */
1923 	vap->va_type = vp->v_type;
1924 	vap->va_mode = ip->i_mode & MODEMASK;
1925 	/*
1926 	 * If there is an ACL and there is a mask entry, then do the
1927 	 * extra work that completes the equivalent of an acltomode(3)
1928 	 * call.  According to POSIX P1003.1e, the acl mask should be
1929 	 * returned in the group permissions field.
1930 	 *
1931 	 * - start with the original permission and mode bits (from above)
1932 	 * - clear the group owner bits
1933 	 * - add in the mask bits.
1934 	 */
1935 	if (ip->i_ufs_acl && ip->i_ufs_acl->aclass.acl_ismask) {
1936 		vap->va_mode &= ~((VREAD | VWRITE | VEXEC) >> 3);
1937 		vap->va_mode |=
1938 		    (ip->i_ufs_acl->aclass.acl_maskbits & PERMMASK) << 3;
1939 	}
1940 	vap->va_uid = ip->i_uid;
1941 	vap->va_gid = ip->i_gid;
1942 	vap->va_fsid = ip->i_dev;
1943 	vap->va_nodeid = (ino64_t)ip->i_number;
1944 	vap->va_nlink = ip->i_nlink;
1945 	vap->va_size = ip->i_size;
1946 	if (vp->v_type == VCHR || vp->v_type == VBLK)
1947 		vap->va_rdev = ip->i_rdev;
1948 	else
1949 		vap->va_rdev = 0;	/* not a b/c spec. */
1950 	mutex_enter(&ip->i_tlock);
1951 	ITIMES_NOLOCK(ip);	/* mark correct time in inode */
1952 	vap->va_seq = ip->i_seq;
1953 	vap->va_atime.tv_sec = (time_t)ip->i_atime.tv_sec;
1954 	vap->va_atime.tv_nsec = ip->i_atime.tv_usec*1000;
1955 	vap->va_mtime.tv_sec = (time_t)ip->i_mtime.tv_sec;
1956 	vap->va_mtime.tv_nsec = ip->i_mtime.tv_usec*1000;
1957 	vap->va_ctime.tv_sec = (time_t)ip->i_ctime.tv_sec;
1958 	vap->va_ctime.tv_nsec = ip->i_ctime.tv_usec*1000;
1959 	mutex_exit(&ip->i_tlock);
1960 
1961 	switch (ip->i_mode & IFMT) {
1962 
1963 	case IFBLK:
1964 		vap->va_blksize = MAXBSIZE;		/* was BLKDEV_IOSIZE */
1965 		break;
1966 
1967 	case IFCHR:
1968 		vap->va_blksize = MAXBSIZE;
1969 		break;
1970 
1971 	default:
1972 		vap->va_blksize = ip->i_fs->fs_bsize;
1973 		break;
1974 	}
1975 	vap->va_nblocks = (fsblkcnt64_t)ip->i_blocks;
1976 	rw_exit(&ip->i_contents);
1977 	err = 0;
1978 
1979 out:
1980 	return (err);
1981 }
1982 
1983 /*
1984  * Special wrapper to provide a callback for secpolicy_vnode_setattr().
1985  * The i_contents lock is already held by the caller and we need to
1986  * declare the inode as 'void *' argument.
1987  */
1988 static int
1989 ufs_priv_access(void *vip, int mode, struct cred *cr)
1990 {
1991 	struct inode *ip = vip;
1992 
1993 	return (ufs_iaccess(ip, mode, cr, 0));
1994 }
1995 
1996 /*ARGSUSED4*/
1997 static int
1998 ufs_setattr(struct vnode *vp, struct vattr *vap, int flags, struct cred *cr,
1999     caller_context_t *ct)
2000 {
2001 	struct inode *ip = VTOI(vp);
2002 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
2003 	struct fs *fs;
2004 	struct ulockfs *ulp;
2005 	char *errmsg1;
2006 	char *errmsg2;
2007 	long blocks;
2008 	long int mask = vap->va_mask;
2009 	size_t len1, len2;
2010 	int issync;
2011 	int trans_size;
2012 	int dotrans;
2013 	int dorwlock;
2014 	int error;
2015 	int owner_change;
2016 	int dodqlock;
2017 	timestruc_t now;
2018 	vattr_t oldva;
2019 	int retry = 1;
2020 	int indeadlock;
2021 
2022 	/*
2023 	 * Cannot set these attributes.
2024 	 */
2025 	if ((mask & AT_NOSET) || (mask & AT_XVATTR))
2026 		return (EINVAL);
2027 
2028 	/*
2029 	 * check for forced unmount
2030 	 */
2031 	if (ufsvfsp == NULL)
2032 		return (EIO);
2033 
2034 	fs = ufsvfsp->vfs_fs;
2035 	if (fs->fs_ronly != 0)
2036 		return (EROFS);
2037 
2038 again:
2039 	errmsg1 = NULL;
2040 	errmsg2 = NULL;
2041 	dotrans = 0;
2042 	dorwlock = 0;
2043 	dodqlock = 0;
2044 
2045 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SETATTR_MASK);
2046 	if (error)
2047 		goto out;
2048 
2049 	/*
2050 	 * Acquire i_rwlock before TRANS_BEGIN_CSYNC() if this is a file.
2051 	 * This follows the protocol for read()/write().
2052 	 */
2053 	if (vp->v_type != VDIR) {
2054 		/*
2055 		 * ufs_tryirwlock uses rw_tryenter and checks for SLOCK to
2056 		 * avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
2057 		 * possible, retries the operation.
2058 		 */
2059 		ufs_tryirwlock(&ip->i_rwlock, RW_WRITER, retry_file);
2060 		if (indeadlock) {
2061 			if (ulp)
2062 				ufs_lockfs_end(ulp);
2063 			goto again;
2064 		}
2065 		dorwlock = 1;
2066 	}
2067 
2068 	/*
2069 	 * Truncate file.  Must have write permission and not be a directory.
2070 	 */
2071 	if (mask & AT_SIZE) {
2072 		rw_enter(&ip->i_contents, RW_WRITER);
2073 		if (vp->v_type == VDIR) {
2074 			error = EISDIR;
2075 			goto update_inode;
2076 		}
2077 		if (error = ufs_iaccess(ip, IWRITE, cr, 0))
2078 			goto update_inode;
2079 
2080 		rw_exit(&ip->i_contents);
2081 		error = TRANS_ITRUNC(ip, vap->va_size, 0, cr);
2082 		if (error) {
2083 			rw_enter(&ip->i_contents, RW_WRITER);
2084 			goto update_inode;
2085 		}
2086 
2087 		if (error == 0 && vap->va_size)
2088 			vnevent_truncate(vp, ct);
2089 	}
2090 
2091 	if (ulp) {
2092 		trans_size = (int)TOP_SETATTR_SIZE(ip);
2093 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_SETATTR, trans_size);
2094 		++dotrans;
2095 	}
2096 
2097 	/*
2098 	 * Acquire i_rwlock after TRANS_BEGIN_CSYNC() if this is a directory.
2099 	 * This follows the protocol established by
2100 	 * ufs_link/create/remove/rename/mkdir/rmdir/symlink.
2101 	 */
2102 	if (vp->v_type == VDIR) {
2103 		ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_SETATTR,
2104 		    retry_dir);
2105 		if (indeadlock)
2106 			goto again;
2107 		dorwlock = 1;
2108 	}
2109 
2110 	/*
2111 	 * Grab quota lock if we are changing the file's owner.
2112 	 */
2113 	if (mask & AT_UID) {
2114 		rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
2115 		dodqlock = 1;
2116 	}
2117 	rw_enter(&ip->i_contents, RW_WRITER);
2118 
2119 	oldva.va_mode = ip->i_mode;
2120 	oldva.va_uid = ip->i_uid;
2121 	oldva.va_gid = ip->i_gid;
2122 
2123 	vap->va_mask &= ~AT_SIZE;
2124 
2125 	error = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags,
2126 	    ufs_priv_access, ip);
2127 	if (error)
2128 		goto update_inode;
2129 
2130 	mask = vap->va_mask;
2131 
2132 	/*
2133 	 * Change file access modes.
2134 	 */
2135 	if (mask & AT_MODE) {
2136 		ip->i_mode = (ip->i_mode & IFMT) | (vap->va_mode & ~IFMT);
2137 		TRANS_INODE(ufsvfsp, ip);
2138 		ip->i_flag |= ICHG;
2139 		if (stickyhack) {
2140 			mutex_enter(&vp->v_lock);
2141 			if ((ip->i_mode & (ISVTX | IEXEC | IFDIR)) == ISVTX)
2142 				vp->v_flag |= VSWAPLIKE;
2143 			else
2144 				vp->v_flag &= ~VSWAPLIKE;
2145 			mutex_exit(&vp->v_lock);
2146 		}
2147 	}
2148 	if (mask & (AT_UID|AT_GID)) {
2149 		if (mask & AT_UID) {
2150 			/*
2151 			 * Don't change ownership of the quota inode.
2152 			 */
2153 			if (ufsvfsp->vfs_qinod == ip) {
2154 				ASSERT(ufsvfsp->vfs_qflags & MQ_ENABLED);
2155 				error = EINVAL;
2156 				goto update_inode;
2157 			}
2158 
2159 			/*
2160 			 * No real ownership change.
2161 			 */
2162 			if (ip->i_uid == vap->va_uid) {
2163 				blocks = 0;
2164 				owner_change = 0;
2165 			}
2166 			/*
2167 			 * Remove the blocks and the file, from the old user's
2168 			 * quota.
2169 			 */
2170 			else {
2171 				blocks = ip->i_blocks;
2172 				owner_change = 1;
2173 
2174 				(void) chkdq(ip, -blocks, /* force */ 1, cr,
2175 				    (char **)NULL, (size_t *)NULL);
2176 				(void) chkiq(ufsvfsp, /* change */ -1, ip,
2177 				    (uid_t)ip->i_uid, /* force */ 1, cr,
2178 				    (char **)NULL, (size_t *)NULL);
2179 				dqrele(ip->i_dquot);
2180 			}
2181 
2182 			ip->i_uid = vap->va_uid;
2183 
2184 			/*
2185 			 * There is a real ownership change.
2186 			 */
2187 			if (owner_change) {
2188 				/*
2189 				 * Add the blocks and the file to the new
2190 				 * user's quota.
2191 				 */
2192 				ip->i_dquot = getinoquota(ip);
2193 				(void) chkdq(ip, blocks, /* force */ 1, cr,
2194 				    &errmsg1, &len1);
2195 				(void) chkiq(ufsvfsp, /* change */ 1,
2196 				    (struct inode *)NULL, (uid_t)ip->i_uid,
2197 				    /* force */ 1, cr, &errmsg2, &len2);
2198 			}
2199 		}
2200 		if (mask & AT_GID) {
2201 			ip->i_gid = vap->va_gid;
2202 		}
2203 		TRANS_INODE(ufsvfsp, ip);
2204 		ip->i_flag |= ICHG;
2205 	}
2206 	/*
2207 	 * Change file access or modified times.
2208 	 */
2209 	if (mask & (AT_ATIME|AT_MTIME)) {
2210 		/* Check that the time value is within ufs range */
2211 		if (((mask & AT_ATIME) && TIMESPEC_OVERFLOW(&vap->va_atime)) ||
2212 		    ((mask & AT_MTIME) && TIMESPEC_OVERFLOW(&vap->va_mtime))) {
2213 			error = EOVERFLOW;
2214 			goto update_inode;
2215 		}
2216 
2217 		/*
2218 		 * if the "noaccess" mount option is set and only atime
2219 		 * update is requested, do nothing. No error is returned.
2220 		 */
2221 		if ((ufsvfsp->vfs_noatime) &&
2222 		    ((mask & (AT_ATIME|AT_MTIME)) == AT_ATIME))
2223 			goto skip_atime;
2224 
2225 		if (mask & AT_ATIME) {
2226 			ip->i_atime.tv_sec = vap->va_atime.tv_sec;
2227 			ip->i_atime.tv_usec = vap->va_atime.tv_nsec / 1000;
2228 			ip->i_flag &= ~IACC;
2229 		}
2230 		if (mask & AT_MTIME) {
2231 			ip->i_mtime.tv_sec = vap->va_mtime.tv_sec;
2232 			ip->i_mtime.tv_usec = vap->va_mtime.tv_nsec / 1000;
2233 			gethrestime(&now);
2234 			if (now.tv_sec > TIME32_MAX) {
2235 				/*
2236 				 * In 2038, ctime sticks forever..
2237 				 */
2238 				ip->i_ctime.tv_sec = TIME32_MAX;
2239 				ip->i_ctime.tv_usec = 0;
2240 			} else {
2241 				ip->i_ctime.tv_sec = now.tv_sec;
2242 				ip->i_ctime.tv_usec = now.tv_nsec / 1000;
2243 			}
2244 			ip->i_flag &= ~(IUPD|ICHG);
2245 			ip->i_flag |= IMODTIME;
2246 		}
2247 		TRANS_INODE(ufsvfsp, ip);
2248 		ip->i_flag |= IMOD;
2249 	}
2250 
2251 skip_atime:
2252 	/*
2253 	 * The presence of a shadow inode may indicate an ACL, but does
2254 	 * not imply an ACL.  Future FSD types should be handled here too
2255 	 * and check for the presence of the attribute-specific data
2256 	 * before referencing it.
2257 	 */
2258 	if (ip->i_shadow) {
2259 		/*
2260 		 * XXX if ufs_iupdat is changed to sandbagged write fix
2261 		 * ufs_acl_setattr to push ip to keep acls consistent
2262 		 *
2263 		 * Suppress out of inodes messages if we will retry.
2264 		 */
2265 		if (retry)
2266 			ip->i_flag |= IQUIET;
2267 		error = ufs_acl_setattr(ip, vap, cr);
2268 		ip->i_flag &= ~IQUIET;
2269 	}
2270 
2271 update_inode:
2272 	/*
2273 	 * Setattr always increases the sequence number
2274 	 */
2275 	ip->i_seq++;
2276 
2277 	/*
2278 	 * if nfsd and not logging; push synchronously
2279 	 */
2280 	if ((curthread->t_flag & T_DONTPEND) && !TRANS_ISTRANS(ufsvfsp)) {
2281 		ufs_iupdat(ip, 1);
2282 	} else {
2283 		ITIMES_NOLOCK(ip);
2284 	}
2285 
2286 	rw_exit(&ip->i_contents);
2287 	if (dodqlock) {
2288 		rw_exit(&ufsvfsp->vfs_dqrwlock);
2289 	}
2290 	if (dorwlock)
2291 		rw_exit(&ip->i_rwlock);
2292 
2293 	if (ulp) {
2294 		if (dotrans) {
2295 			int terr = 0;
2296 			TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_SETATTR,
2297 			    trans_size);
2298 			if (error == 0)
2299 				error = terr;
2300 		}
2301 		ufs_lockfs_end(ulp);
2302 	}
2303 out:
2304 	/*
2305 	 * If out of inodes or blocks, see if we can free something
2306 	 * up from the delete queue.
2307 	 */
2308 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
2309 		ufs_delete_drain_wait(ufsvfsp, 1);
2310 		retry = 0;
2311 		if (errmsg1 != NULL)
2312 			kmem_free(errmsg1, len1);
2313 		if (errmsg2 != NULL)
2314 			kmem_free(errmsg2, len2);
2315 		goto again;
2316 	}
2317 	if (errmsg1 != NULL) {
2318 		uprintf(errmsg1);
2319 		kmem_free(errmsg1, len1);
2320 	}
2321 	if (errmsg2 != NULL) {
2322 		uprintf(errmsg2);
2323 		kmem_free(errmsg2, len2);
2324 	}
2325 	return (error);
2326 }
2327 
2328 /*ARGSUSED*/
2329 static int
2330 ufs_access(struct vnode *vp, int mode, int flags, struct cred *cr,
2331     caller_context_t *ct)
2332 {
2333 	struct inode *ip = VTOI(vp);
2334 
2335 	if (ip->i_ufsvfs == NULL)
2336 		return (EIO);
2337 
2338 	/*
2339 	 * The ufs_iaccess function wants to be called with
2340 	 * mode bits expressed as "ufs specific" bits.
2341 	 * I.e., VWRITE|VREAD|VEXEC do not make sense to
2342 	 * ufs_iaccess() but IWRITE|IREAD|IEXEC do.
2343 	 * But since they're the same we just pass the vnode mode
2344 	 * bit but just verify that assumption at compile time.
2345 	 */
2346 #if IWRITE != VWRITE || IREAD != VREAD || IEXEC != VEXEC
2347 #error "ufs_access needs to map Vmodes to Imodes"
2348 #endif
2349 	return (ufs_iaccess(ip, mode, cr, 1));
2350 }
2351 
2352 /* ARGSUSED */
2353 static int
2354 ufs_readlink(struct vnode *vp, struct uio *uiop, struct cred *cr,
2355     caller_context_t *ct)
2356 {
2357 	struct inode *ip = VTOI(vp);
2358 	struct ufsvfs *ufsvfsp;
2359 	struct ulockfs *ulp;
2360 	int error;
2361 	int fastsymlink;
2362 
2363 	if (vp->v_type != VLNK) {
2364 		error = EINVAL;
2365 		goto nolockout;
2366 	}
2367 
2368 	/*
2369 	 * If the symbolic link is empty there is nothing to read.
2370 	 * Fast-track these empty symbolic links
2371 	 */
2372 	if (ip->i_size == 0) {
2373 		error = 0;
2374 		goto nolockout;
2375 	}
2376 
2377 	ufsvfsp = ip->i_ufsvfs;
2378 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_READLINK_MASK);
2379 	if (error)
2380 		goto nolockout;
2381 	/*
2382 	 * The ip->i_rwlock protects the data blocks used for FASTSYMLINK
2383 	 */
2384 again:
2385 	fastsymlink = 0;
2386 	if (ip->i_flag & IFASTSYMLNK) {
2387 		rw_enter(&ip->i_rwlock, RW_READER);
2388 		rw_enter(&ip->i_contents, RW_READER);
2389 		if (ip->i_flag & IFASTSYMLNK) {
2390 			if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) &&
2391 			    (ip->i_fs->fs_ronly == 0) &&
2392 			    (!ufsvfsp->vfs_noatime)) {
2393 				mutex_enter(&ip->i_tlock);
2394 				ip->i_flag |= IACC;
2395 				mutex_exit(&ip->i_tlock);
2396 			}
2397 			error = uiomove((caddr_t)&ip->i_db[1],
2398 			    MIN(ip->i_size, uiop->uio_resid),
2399 			    UIO_READ, uiop);
2400 			ITIMES(ip);
2401 			++fastsymlink;
2402 		}
2403 		rw_exit(&ip->i_contents);
2404 		rw_exit(&ip->i_rwlock);
2405 	}
2406 	if (!fastsymlink) {
2407 		ssize_t size;	/* number of bytes read  */
2408 		caddr_t basep;	/* pointer to input data */
2409 		ino_t ino;
2410 		long  igen;
2411 		struct uio tuio;	/* temp uio struct */
2412 		struct uio *tuiop;
2413 		iovec_t tiov;		/* temp iovec struct */
2414 		char kbuf[FSL_SIZE];	/* buffer to hold fast symlink */
2415 		int tflag = 0;		/* flag to indicate temp vars used */
2416 
2417 		ino = ip->i_number;
2418 		igen = ip->i_gen;
2419 		size = uiop->uio_resid;
2420 		basep = uiop->uio_iov->iov_base;
2421 		tuiop = uiop;
2422 
2423 		rw_enter(&ip->i_rwlock, RW_WRITER);
2424 		rw_enter(&ip->i_contents, RW_WRITER);
2425 		if (ip->i_flag & IFASTSYMLNK) {
2426 			rw_exit(&ip->i_contents);
2427 			rw_exit(&ip->i_rwlock);
2428 			goto again;
2429 		}
2430 
2431 		/* can this be a fast symlink and is it a user buffer? */
2432 		if (ip->i_size <= FSL_SIZE &&
2433 		    (uiop->uio_segflg == UIO_USERSPACE ||
2434 		    uiop->uio_segflg == UIO_USERISPACE)) {
2435 
2436 			bzero(&tuio, sizeof (struct uio));
2437 			/*
2438 			 * setup a kernel buffer to read link into.  this
2439 			 * is to fix a race condition where the user buffer
2440 			 * got corrupted before copying it into the inode.
2441 			 */
2442 			size = ip->i_size;
2443 			tiov.iov_len = size;
2444 			tiov.iov_base = kbuf;
2445 			tuio.uio_iov = &tiov;
2446 			tuio.uio_iovcnt = 1;
2447 			tuio.uio_offset = uiop->uio_offset;
2448 			tuio.uio_segflg = UIO_SYSSPACE;
2449 			tuio.uio_fmode = uiop->uio_fmode;
2450 			tuio.uio_extflg = uiop->uio_extflg;
2451 			tuio.uio_limit = uiop->uio_limit;
2452 			tuio.uio_resid = size;
2453 
2454 			basep = tuio.uio_iov->iov_base;
2455 			tuiop = &tuio;
2456 			tflag = 1;
2457 		}
2458 
2459 		error = rdip(ip, tuiop, 0, cr);
2460 		if (!(error == 0 && ip->i_number == ino && ip->i_gen == igen)) {
2461 			rw_exit(&ip->i_contents);
2462 			rw_exit(&ip->i_rwlock);
2463 			goto out;
2464 		}
2465 
2466 		if (tflag == 0)
2467 			size -= uiop->uio_resid;
2468 
2469 		if ((tflag == 0 && ip->i_size <= FSL_SIZE &&
2470 		    ip->i_size == size) || (tflag == 1 &&
2471 		    tuio.uio_resid == 0)) {
2472 			error = kcopy(basep, &ip->i_db[1], ip->i_size);
2473 			if (error == 0) {
2474 				ip->i_flag |= IFASTSYMLNK;
2475 				/*
2476 				 * free page
2477 				 */
2478 				(void) VOP_PUTPAGE(ITOV(ip),
2479 				    (offset_t)0, PAGESIZE,
2480 				    (B_DONTNEED | B_FREE | B_FORCE | B_ASYNC),
2481 				    cr, ct);
2482 			} else {
2483 				int i;
2484 				/* error, clear garbage left behind */
2485 				for (i = 1; i < NDADDR; i++)
2486 					ip->i_db[i] = 0;
2487 				for (i = 0; i < NIADDR; i++)
2488 					ip->i_ib[i] = 0;
2489 			}
2490 		}
2491 		if (tflag == 1) {
2492 			/* now, copy it into the user buffer */
2493 			error = uiomove((caddr_t)kbuf,
2494 			    MIN(size, uiop->uio_resid),
2495 			    UIO_READ, uiop);
2496 		}
2497 		rw_exit(&ip->i_contents);
2498 		rw_exit(&ip->i_rwlock);
2499 	}
2500 out:
2501 	if (ulp) {
2502 		ufs_lockfs_end(ulp);
2503 	}
2504 nolockout:
2505 	return (error);
2506 }
2507 
2508 /* ARGSUSED */
2509 static int
2510 ufs_fsync(struct vnode *vp, int syncflag, struct cred *cr, caller_context_t *ct)
2511 {
2512 	struct inode *ip = VTOI(vp);
2513 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
2514 	struct ulockfs *ulp;
2515 	int error;
2516 
2517 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_FSYNC_MASK);
2518 	if (error)
2519 		return (error);
2520 
2521 	if (TRANS_ISTRANS(ufsvfsp)) {
2522 		/*
2523 		 * First push out any data pages
2524 		 */
2525 		if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) &&
2526 		    (vp->v_type != VCHR) && !(IS_SWAPVP(vp))) {
2527 			error = VOP_PUTPAGE(vp, (offset_t)0, (size_t)0,
2528 			    0, CRED(), ct);
2529 			if (error)
2530 				goto out;
2531 		}
2532 
2533 		/*
2534 		 * Delta any delayed inode times updates
2535 		 * and push inode to log.
2536 		 * All other inode deltas will have already been delta'd
2537 		 * and will be pushed during the commit.
2538 		 */
2539 		if (!(syncflag & FDSYNC) &&
2540 		    ((ip->i_flag & (IMOD|IMODACC)) == IMODACC)) {
2541 			if (ulp) {
2542 				TRANS_BEGIN_ASYNC(ufsvfsp, TOP_FSYNC,
2543 				    TOP_SYNCIP_SIZE);
2544 			}
2545 			rw_enter(&ip->i_contents, RW_READER);
2546 			mutex_enter(&ip->i_tlock);
2547 			ip->i_flag &= ~IMODTIME;
2548 			mutex_exit(&ip->i_tlock);
2549 			ufs_iupdat(ip, I_SYNC);
2550 			rw_exit(&ip->i_contents);
2551 			if (ulp) {
2552 				TRANS_END_ASYNC(ufsvfsp, TOP_FSYNC,
2553 				    TOP_SYNCIP_SIZE);
2554 			}
2555 		}
2556 
2557 		/*
2558 		 * Commit the Moby transaction
2559 		 *
2560 		 * Deltas have already been made so we just need to
2561 		 * commit them with a synchronous transaction.
2562 		 * TRANS_BEGIN_SYNC() will return an error
2563 		 * if there are no deltas to commit, for an
2564 		 * empty transaction.
2565 		 */
2566 		if (ulp) {
2567 			TRANS_BEGIN_SYNC(ufsvfsp, TOP_FSYNC, TOP_COMMIT_SIZE,
2568 			    error);
2569 			if (error) {
2570 				error = 0; /* commit wasn't needed */
2571 				goto out;
2572 			}
2573 			TRANS_END_SYNC(ufsvfsp, error, TOP_FSYNC,
2574 			    TOP_COMMIT_SIZE);
2575 		}
2576 	} else {	/* not logging */
2577 		if (!(IS_SWAPVP(vp)))
2578 			if (syncflag & FNODSYNC) {
2579 				/* Just update the inode only */
2580 				TRANS_IUPDAT(ip, 1);
2581 				error = 0;
2582 			} else if (syncflag & FDSYNC)
2583 				/* Do data-synchronous writes */
2584 				error = TRANS_SYNCIP(ip, 0, I_DSYNC, TOP_FSYNC);
2585 			else
2586 				/* Do synchronous writes */
2587 				error = TRANS_SYNCIP(ip, 0, I_SYNC, TOP_FSYNC);
2588 
2589 		rw_enter(&ip->i_contents, RW_WRITER);
2590 		if (!error)
2591 			error = ufs_sync_indir(ip);
2592 		rw_exit(&ip->i_contents);
2593 	}
2594 out:
2595 	if (ulp) {
2596 		ufs_lockfs_end(ulp);
2597 	}
2598 	return (error);
2599 }
2600 
2601 /*ARGSUSED*/
2602 static void
2603 ufs_inactive(struct vnode *vp, struct cred *cr, caller_context_t *ct)
2604 {
2605 	ufs_iinactive(VTOI(vp));
2606 }
2607 
2608 /*
2609  * Unix file system operations having to do with directory manipulation.
2610  */
2611 int ufs_lookup_idle_count = 2;	/* Number of inodes to idle each time */
2612 /* ARGSUSED */
2613 static int
2614 ufs_lookup(struct vnode *dvp, char *nm, struct vnode **vpp,
2615     struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cr,
2616     caller_context_t *ct, int *direntflags, pathname_t *realpnp)
2617 {
2618 	struct inode *ip;
2619 	struct inode *sip;
2620 	struct inode *xip;
2621 	struct ufsvfs *ufsvfsp;
2622 	struct ulockfs *ulp;
2623 	struct vnode *vp;
2624 	int error;
2625 
2626 	/*
2627 	 * Check flags for type of lookup (regular file or attribute file)
2628 	 */
2629 
2630 	ip = VTOI(dvp);
2631 
2632 	if (flags & LOOKUP_XATTR) {
2633 
2634 		/*
2635 		 * If not mounted with XATTR support then return EINVAL
2636 		 */
2637 
2638 		if (!(ip->i_ufsvfs->vfs_vfs->vfs_flag & VFS_XATTR))
2639 			return (EINVAL);
2640 		/*
2641 		 * We don't allow recursive attributes...
2642 		 * Maybe someday we will.
2643 		 */
2644 		if ((ip->i_cflags & IXATTR)) {
2645 			return (EINVAL);
2646 		}
2647 
2648 		if ((vp = dnlc_lookup(dvp, XATTR_DIR_NAME)) == NULL) {
2649 			error = ufs_xattr_getattrdir(dvp, &sip, flags, cr);
2650 			if (error) {
2651 				*vpp = NULL;
2652 				goto out;
2653 			}
2654 
2655 			vp = ITOV(sip);
2656 			dnlc_update(dvp, XATTR_DIR_NAME, vp);
2657 		}
2658 
2659 		/*
2660 		 * Check accessibility of directory.
2661 		 */
2662 		if (vp == DNLC_NO_VNODE) {
2663 			VN_RELE(vp);
2664 			error = ENOENT;
2665 			goto out;
2666 		}
2667 		if ((error = ufs_iaccess(VTOI(vp), IEXEC, cr, 1)) != 0) {
2668 			VN_RELE(vp);
2669 			goto out;
2670 		}
2671 
2672 		*vpp = vp;
2673 		return (0);
2674 	}
2675 
2676 	/*
2677 	 * Check for a null component, which we should treat as
2678 	 * looking at dvp from within it's parent, so we don't
2679 	 * need a call to ufs_iaccess(), as it has already been
2680 	 * done.
2681 	 */
2682 	if (nm[0] == 0) {
2683 		VN_HOLD(dvp);
2684 		error = 0;
2685 		*vpp = dvp;
2686 		goto out;
2687 	}
2688 
2689 	/*
2690 	 * Check for "." ie itself. this is a quick check and
2691 	 * avoids adding "." into the dnlc (which have been seen
2692 	 * to occupy >10% of the cache).
2693 	 */
2694 	if ((nm[0] == '.') && (nm[1] == 0)) {
2695 		/*
2696 		 * Don't return without checking accessibility
2697 		 * of the directory. We only need the lock if
2698 		 * we are going to return it.
2699 		 */
2700 		if ((error = ufs_iaccess(ip, IEXEC, cr, 1)) == 0) {
2701 			VN_HOLD(dvp);
2702 			*vpp = dvp;
2703 		}
2704 		goto out;
2705 	}
2706 
2707 	/*
2708 	 * Fast path: Check the directory name lookup cache.
2709 	 */
2710 	if (vp = dnlc_lookup(dvp, nm)) {
2711 		/*
2712 		 * Check accessibility of directory.
2713 		 */
2714 		if ((error = ufs_iaccess(ip, IEXEC, cr, 1)) != 0) {
2715 			VN_RELE(vp);
2716 			goto out;
2717 		}
2718 		if (vp == DNLC_NO_VNODE) {
2719 			VN_RELE(vp);
2720 			error = ENOENT;
2721 			goto out;
2722 		}
2723 		xip = VTOI(vp);
2724 		ulp = NULL;
2725 		goto fastpath;
2726 	}
2727 
2728 	/*
2729 	 * Keep the idle queue from getting too long by
2730 	 * idling two inodes before attempting to allocate another.
2731 	 *    This operation must be performed before entering
2732 	 *    lockfs or a transaction.
2733 	 */
2734 	if (ufs_idle_q.uq_ne > ufs_idle_q.uq_hiwat)
2735 		if ((curthread->t_flag & T_DONTBLOCK) == 0) {
2736 			ins.in_lidles.value.ul += ufs_lookup_idle_count;
2737 			ufs_idle_some(ufs_lookup_idle_count);
2738 		}
2739 
2740 retry_lookup:
2741 	/*
2742 	 * Check accessibility of directory.
2743 	 */
2744 	if (error = ufs_diraccess(ip, IEXEC, cr))
2745 		goto out;
2746 
2747 	ufsvfsp = ip->i_ufsvfs;
2748 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LOOKUP_MASK);
2749 	if (error)
2750 		goto out;
2751 
2752 	error = ufs_dirlook(ip, nm, &xip, cr, 1, 0);
2753 
2754 fastpath:
2755 	if (error == 0) {
2756 		ip = xip;
2757 		*vpp = ITOV(ip);
2758 
2759 		/*
2760 		 * If vnode is a device return special vnode instead.
2761 		 */
2762 		if (IS_DEVVP(*vpp)) {
2763 			struct vnode *newvp;
2764 
2765 			newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type,
2766 			    cr);
2767 			VN_RELE(*vpp);
2768 			if (newvp == NULL)
2769 				error = ENOSYS;
2770 			else
2771 				*vpp = newvp;
2772 		} else if (ip->i_cflags & ICOMPRESS) {
2773 			struct vnode *newvp;
2774 
2775 			/*
2776 			 * Compressed file, substitute dcfs vnode
2777 			 */
2778 			newvp = decompvp(*vpp, cr, ct);
2779 			VN_RELE(*vpp);
2780 			if (newvp == NULL)
2781 				error = ENOSYS;
2782 			else
2783 				*vpp = newvp;
2784 		}
2785 	}
2786 	if (ulp) {
2787 		ufs_lockfs_end(ulp);
2788 	}
2789 
2790 	if (error == EAGAIN)
2791 		goto retry_lookup;
2792 
2793 out:
2794 	return (error);
2795 }
2796 
2797 /*ARGSUSED*/
2798 static int
2799 ufs_create(struct vnode *dvp, char *name, struct vattr *vap, enum vcexcl excl,
2800     int mode, struct vnode **vpp, struct cred *cr, int flag,
2801     caller_context_t *ct, vsecattr_t *vsecp)
2802 {
2803 	struct inode *ip;
2804 	struct inode *xip;
2805 	struct inode *dip;
2806 	struct vnode *xvp;
2807 	struct ufsvfs *ufsvfsp;
2808 	struct ulockfs *ulp;
2809 	int error;
2810 	int issync;
2811 	int truncflag;
2812 	int trans_size;
2813 	int noentry;
2814 	int defer_dip_seq_update = 0;	/* need to defer update of dip->i_seq */
2815 	int retry = 1;
2816 	int indeadlock;
2817 
2818 again:
2819 	ip = VTOI(dvp);
2820 	ufsvfsp = ip->i_ufsvfs;
2821 	truncflag = 0;
2822 
2823 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_CREATE_MASK);
2824 	if (error)
2825 		goto out;
2826 
2827 	if (ulp) {
2828 		trans_size = (int)TOP_CREATE_SIZE(ip);
2829 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_CREATE, trans_size);
2830 	}
2831 
2832 	if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr) != 0)
2833 		vap->va_mode &= ~VSVTX;
2834 
2835 	if (*name == '\0') {
2836 		/*
2837 		 * Null component name refers to the directory itself.
2838 		 */
2839 		VN_HOLD(dvp);
2840 		/*
2841 		 * Even though this is an error case, we need to grab the
2842 		 * quota lock since the error handling code below is common.
2843 		 */
2844 		rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
2845 		rw_enter(&ip->i_contents, RW_WRITER);
2846 		error = EEXIST;
2847 	} else {
2848 		xip = NULL;
2849 		noentry = 0;
2850 		/*
2851 		 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
2852 		 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
2853 		 * possible, retries the operation.
2854 		 */
2855 		ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_CREATE,
2856 		    retry_dir);
2857 		if (indeadlock)
2858 			goto again;
2859 
2860 		xvp = dnlc_lookup(dvp, name);
2861 		if (xvp == DNLC_NO_VNODE) {
2862 			noentry = 1;
2863 			VN_RELE(xvp);
2864 			xvp = NULL;
2865 		}
2866 		if (xvp) {
2867 			rw_exit(&ip->i_rwlock);
2868 			if (error = ufs_iaccess(ip, IEXEC, cr, 1)) {
2869 				VN_RELE(xvp);
2870 			} else {
2871 				error = EEXIST;
2872 				xip = VTOI(xvp);
2873 			}
2874 		} else {
2875 			/*
2876 			 * Suppress file system full message if we will retry
2877 			 */
2878 			error = ufs_direnter_cm(ip, name, DE_CREATE,
2879 			    vap, &xip, cr, (noentry | (retry ? IQUIET : 0)));
2880 			if (error == EAGAIN) {
2881 				if (ulp) {
2882 					TRANS_END_CSYNC(ufsvfsp, error, issync,
2883 					    TOP_CREATE, trans_size);
2884 					ufs_lockfs_end(ulp);
2885 				}
2886 				goto again;
2887 			}
2888 			rw_exit(&ip->i_rwlock);
2889 		}
2890 		ip = xip;
2891 		if (ip != NULL) {
2892 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
2893 			rw_enter(&ip->i_contents, RW_WRITER);
2894 		}
2895 	}
2896 
2897 	/*
2898 	 * If the file already exists and this is a non-exclusive create,
2899 	 * check permissions and allow access for non-directories.
2900 	 * Read-only create of an existing directory is also allowed.
2901 	 * We fail an exclusive create of anything which already exists.
2902 	 */
2903 	if (error == EEXIST) {
2904 		dip = VTOI(dvp);
2905 		if (excl == NONEXCL) {
2906 			if ((((ip->i_mode & IFMT) == IFDIR) ||
2907 			    ((ip->i_mode & IFMT) == IFATTRDIR)) &&
2908 			    (mode & IWRITE))
2909 				error = EISDIR;
2910 			else if (mode)
2911 				error = ufs_iaccess(ip, mode, cr, 0);
2912 			else
2913 				error = 0;
2914 		}
2915 		if (error) {
2916 			rw_exit(&ip->i_contents);
2917 			rw_exit(&ufsvfsp->vfs_dqrwlock);
2918 			VN_RELE(ITOV(ip));
2919 			goto unlock;
2920 		}
2921 		/*
2922 		 * If the error EEXIST was set, then i_seq can not
2923 		 * have been updated. The sequence number interface
2924 		 * is defined such that a non-error VOP_CREATE must
2925 		 * increase the dir va_seq it by at least one. If we
2926 		 * have cleared the error, increase i_seq. Note that
2927 		 * we are increasing the dir i_seq and in rare cases
2928 		 * ip may actually be from the dvp, so we already have
2929 		 * the locks and it will not be subject to truncation.
2930 		 * In case we have to update i_seq of the parent
2931 		 * directory dip, we have to defer it till we have
2932 		 * released our locks on ip due to lock ordering requirements.
2933 		 */
2934 		if (ip != dip)
2935 			defer_dip_seq_update = 1;
2936 		else
2937 			ip->i_seq++;
2938 
2939 		if (((ip->i_mode & IFMT) == IFREG) &&
2940 		    (vap->va_mask & AT_SIZE) && vap->va_size == 0) {
2941 			/*
2942 			 * Truncate regular files, if requested by caller.
2943 			 * Grab i_rwlock to make sure no one else is
2944 			 * currently writing to the file (we promised
2945 			 * bmap we would do this).
2946 			 * Must get the locks in the correct order.
2947 			 */
2948 			if (ip->i_size == 0) {
2949 				ip->i_flag |= ICHG | IUPD;
2950 				ip->i_seq++;
2951 				TRANS_INODE(ufsvfsp, ip);
2952 			} else {
2953 				/*
2954 				 * Large Files: Why this check here?
2955 				 * Though we do it in vn_create() we really
2956 				 * want to guarantee that we do not destroy
2957 				 * Large file data by atomically checking
2958 				 * the size while holding the contents
2959 				 * lock.
2960 				 */
2961 				if (flag && !(flag & FOFFMAX) &&
2962 				    ((ip->i_mode & IFMT) == IFREG) &&
2963 				    (ip->i_size > (offset_t)MAXOFF32_T)) {
2964 					rw_exit(&ip->i_contents);
2965 					rw_exit(&ufsvfsp->vfs_dqrwlock);
2966 					error = EOVERFLOW;
2967 					goto unlock;
2968 				}
2969 				if (TRANS_ISTRANS(ufsvfsp))
2970 					truncflag++;
2971 				else {
2972 					rw_exit(&ip->i_contents);
2973 					rw_exit(&ufsvfsp->vfs_dqrwlock);
2974 					ufs_tryirwlock_trans(&ip->i_rwlock,
2975 					    RW_WRITER, TOP_CREATE,
2976 					    retry_file);
2977 					if (indeadlock) {
2978 						VN_RELE(ITOV(ip));
2979 						goto again;
2980 					}
2981 					rw_enter(&ufsvfsp->vfs_dqrwlock,
2982 					    RW_READER);
2983 					rw_enter(&ip->i_contents, RW_WRITER);
2984 					(void) ufs_itrunc(ip, (u_offset_t)0, 0,
2985 					    cr);
2986 					rw_exit(&ip->i_rwlock);
2987 				}
2988 
2989 			}
2990 			if (error == 0) {
2991 				vnevent_create(ITOV(ip), ct);
2992 			}
2993 		}
2994 	}
2995 
2996 	if (error) {
2997 		if (ip != NULL) {
2998 			rw_exit(&ufsvfsp->vfs_dqrwlock);
2999 			rw_exit(&ip->i_contents);
3000 		}
3001 		goto unlock;
3002 	}
3003 
3004 	*vpp = ITOV(ip);
3005 	ITIMES(ip);
3006 	rw_exit(&ip->i_contents);
3007 	rw_exit(&ufsvfsp->vfs_dqrwlock);
3008 
3009 	/*
3010 	 * If vnode is a device return special vnode instead.
3011 	 */
3012 	if (!error && IS_DEVVP(*vpp)) {
3013 		struct vnode *newvp;
3014 
3015 		newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
3016 		VN_RELE(*vpp);
3017 		if (newvp == NULL) {
3018 			error = ENOSYS;
3019 			goto unlock;
3020 		}
3021 		truncflag = 0;
3022 		*vpp = newvp;
3023 	}
3024 unlock:
3025 
3026 	/*
3027 	 * Do the deferred update of the parent directory's sequence
3028 	 * number now.
3029 	 */
3030 	if (defer_dip_seq_update == 1) {
3031 		rw_enter(&dip->i_contents, RW_READER);
3032 		mutex_enter(&dip->i_tlock);
3033 		dip->i_seq++;
3034 		mutex_exit(&dip->i_tlock);
3035 		rw_exit(&dip->i_contents);
3036 	}
3037 
3038 	if (ulp) {
3039 		int terr = 0;
3040 
3041 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_CREATE,
3042 		    trans_size);
3043 
3044 		/*
3045 		 * If we haven't had a more interesting failure
3046 		 * already, then anything that might've happened
3047 		 * here should be reported.
3048 		 */
3049 		if (error == 0)
3050 			error = terr;
3051 	}
3052 
3053 	if (!error && truncflag) {
3054 		ufs_tryirwlock(&ip->i_rwlock, RW_WRITER, retry_trunc);
3055 		if (indeadlock) {
3056 			if (ulp)
3057 				ufs_lockfs_end(ulp);
3058 			VN_RELE(ITOV(ip));
3059 			goto again;
3060 		}
3061 		(void) TRANS_ITRUNC(ip, (u_offset_t)0, 0, cr);
3062 		rw_exit(&ip->i_rwlock);
3063 	}
3064 
3065 	if (ulp)
3066 		ufs_lockfs_end(ulp);
3067 
3068 	/*
3069 	 * If no inodes available, try to free one up out of the
3070 	 * pending delete queue.
3071 	 */
3072 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
3073 		ufs_delete_drain_wait(ufsvfsp, 1);
3074 		retry = 0;
3075 		goto again;
3076 	}
3077 
3078 out:
3079 	return (error);
3080 }
3081 
3082 extern int ufs_idle_max;
3083 /*ARGSUSED*/
3084 static int
3085 ufs_remove(struct vnode *vp, char *nm, struct cred *cr, caller_context_t *ct,
3086     int flags)
3087 {
3088 	struct inode *ip = VTOI(vp);
3089 	struct ufsvfs *ufsvfsp	= ip->i_ufsvfs;
3090 	struct ulockfs *ulp;
3091 	vnode_t *rmvp = NULL;	/* Vnode corresponding to name being removed */
3092 	int indeadlock;
3093 	int error;
3094 	int issync;
3095 	int trans_size;
3096 
3097 	/*
3098 	 * don't let the delete queue get too long
3099 	 */
3100 	if (ufsvfsp == NULL) {
3101 		error = EIO;
3102 		goto out;
3103 	}
3104 	if (ufsvfsp->vfs_delete.uq_ne > ufs_idle_max)
3105 		ufs_delete_drain(vp->v_vfsp, 1, 1);
3106 
3107 	error = ufs_eventlookup(vp, nm, cr, &rmvp);
3108 	if (rmvp != NULL) {
3109 		/* Only send the event if there were no errors */
3110 		if (error == 0)
3111 			vnevent_remove(rmvp, vp, nm, ct);
3112 		VN_RELE(rmvp);
3113 	}
3114 
3115 retry_remove:
3116 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_REMOVE_MASK);
3117 	if (error)
3118 		goto out;
3119 
3120 	if (ulp)
3121 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_REMOVE,
3122 		    trans_size = (int)TOP_REMOVE_SIZE(VTOI(vp)));
3123 
3124 	/*
3125 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3126 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3127 	 * possible, retries the operation.
3128 	 */
3129 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_REMOVE, retry);
3130 	if (indeadlock)
3131 		goto retry_remove;
3132 	error = ufs_dirremove(ip, nm, (struct inode *)0, (struct vnode *)0,
3133 	    DR_REMOVE, cr);
3134 	rw_exit(&ip->i_rwlock);
3135 
3136 	if (ulp) {
3137 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_REMOVE, trans_size);
3138 		ufs_lockfs_end(ulp);
3139 	}
3140 
3141 out:
3142 	return (error);
3143 }
3144 
3145 /*
3146  * Link a file or a directory.  Only privileged processes are allowed to
3147  * make links to directories.
3148  */
3149 /*ARGSUSED*/
3150 static int
3151 ufs_link(struct vnode *tdvp, struct vnode *svp, char *tnm, struct cred *cr,
3152     caller_context_t *ct, int flags)
3153 {
3154 	struct inode *sip;
3155 	struct inode *tdp = VTOI(tdvp);
3156 	struct ufsvfs *ufsvfsp = tdp->i_ufsvfs;
3157 	struct ulockfs *ulp;
3158 	struct vnode *realvp;
3159 	int error;
3160 	int issync;
3161 	int trans_size;
3162 	int isdev;
3163 	int indeadlock;
3164 
3165 retry_link:
3166 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LINK_MASK);
3167 	if (error)
3168 		goto out;
3169 
3170 	if (ulp)
3171 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_LINK,
3172 		    trans_size = (int)TOP_LINK_SIZE(VTOI(tdvp)));
3173 
3174 	if (VOP_REALVP(svp, &realvp, ct) == 0)
3175 		svp = realvp;
3176 
3177 	/*
3178 	 * Make sure link for extended attributes is valid
3179 	 * We only support hard linking of attr in ATTRDIR to ATTRDIR
3180 	 *
3181 	 * Make certain we don't attempt to look at a device node as
3182 	 * a ufs inode.
3183 	 */
3184 
3185 	isdev = IS_DEVVP(svp);
3186 	if (((isdev == 0) && ((VTOI(svp)->i_cflags & IXATTR) == 0) &&
3187 	    ((tdp->i_mode & IFMT) == IFATTRDIR)) ||
3188 	    ((isdev == 0) && (VTOI(svp)->i_cflags & IXATTR) &&
3189 	    ((tdp->i_mode & IFMT) == IFDIR))) {
3190 		error = EINVAL;
3191 		goto unlock;
3192 	}
3193 
3194 	sip = VTOI(svp);
3195 	if ((svp->v_type == VDIR &&
3196 	    secpolicy_fs_linkdir(cr, ufsvfsp->vfs_vfs) != 0) ||
3197 	    (sip->i_uid != crgetuid(cr) && secpolicy_basic_link(cr) != 0)) {
3198 		error = EPERM;
3199 		goto unlock;
3200 	}
3201 
3202 	/*
3203 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3204 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3205 	 * possible, retries the operation.
3206 	 */
3207 	ufs_tryirwlock_trans(&tdp->i_rwlock, RW_WRITER, TOP_LINK, retry);
3208 	if (indeadlock)
3209 		goto retry_link;
3210 	error = ufs_direnter_lr(tdp, tnm, DE_LINK, (struct inode *)0,
3211 	    sip, cr);
3212 	rw_exit(&tdp->i_rwlock);
3213 
3214 unlock:
3215 	if (ulp) {
3216 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_LINK, trans_size);
3217 		ufs_lockfs_end(ulp);
3218 	}
3219 
3220 	if (!error) {
3221 		vnevent_link(svp, ct);
3222 	}
3223 out:
3224 	return (error);
3225 }
3226 
3227 uint64_t ufs_rename_retry_cnt;
3228 uint64_t ufs_rename_upgrade_retry_cnt;
3229 uint64_t ufs_rename_dircheck_retry_cnt;
3230 clock_t	 ufs_rename_backoff_delay = 1;
3231 
3232 /*
3233  * Rename a file or directory.
3234  * We are given the vnode and entry string of the source and the
3235  * vnode and entry string of the place we want to move the source
3236  * to (the target). The essential operation is:
3237  *	unlink(target);
3238  *	link(source, target);
3239  *	unlink(source);
3240  * but "atomically".  Can't do full commit without saving state in
3241  * the inode on disk, which isn't feasible at this time.  Best we
3242  * can do is always guarantee that the TARGET exists.
3243  */
3244 
3245 /*ARGSUSED*/
3246 static int
3247 ufs_rename(struct vnode *sdvp, char *snm, struct vnode *tdvp, char *tnm,
3248     struct cred *cr, caller_context_t *ct, int flags)
3249 {
3250 	struct inode *sip = NULL;	/* source inode */
3251 	struct inode *ip = NULL;	/* check inode */
3252 	struct inode *sdp;		/* old (source) parent inode */
3253 	struct inode *tdp;		/* new (target) parent inode */
3254 	struct vnode *svp = NULL;	/* source vnode */
3255 	struct vnode *tvp = NULL;	/* target vnode, if it exists */
3256 	struct vnode *realvp;
3257 	struct ufsvfs *ufsvfsp;
3258 	struct ulockfs *ulp = NULL;
3259 	struct ufs_slot slot;
3260 	timestruc_t now;
3261 	int error;
3262 	int issync;
3263 	int trans_size;
3264 	krwlock_t *first_lock;
3265 	krwlock_t *second_lock;
3266 	krwlock_t *reverse_lock;
3267 	int serr, terr;
3268 
3269 	sdp = VTOI(sdvp);
3270 	slot.fbp = NULL;
3271 	ufsvfsp = sdp->i_ufsvfs;
3272 
3273 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
3274 		tdvp = realvp;
3275 
3276 	/* Must do this before taking locks in case of DNLC miss */
3277 	terr = ufs_eventlookup(tdvp, tnm, cr, &tvp);
3278 	serr = ufs_eventlookup(sdvp, snm, cr, &svp);
3279 
3280 	if ((serr == 0) && ((terr == 0) || (terr == ENOENT))) {
3281 		if (tvp != NULL)
3282 			vnevent_pre_rename_dest(tvp, tdvp, tnm, ct);
3283 
3284 		/*
3285 		 * Notify the target directory of the rename event
3286 		 * if source and target directories are not the same.
3287 		 */
3288 		if (sdvp != tdvp)
3289 			vnevent_pre_rename_dest_dir(tdvp, svp, tnm, ct);
3290 
3291 		if (svp != NULL)
3292 			vnevent_pre_rename_src(svp, sdvp, snm, ct);
3293 	}
3294 
3295 	if (svp != NULL)
3296 		VN_RELE(svp);
3297 
3298 retry_rename:
3299 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_RENAME_MASK);
3300 	if (error)
3301 		goto unlock;
3302 
3303 	if (ulp)
3304 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_RENAME,
3305 		    trans_size = (int)TOP_RENAME_SIZE(sdp));
3306 
3307 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
3308 		tdvp = realvp;
3309 
3310 	tdp = VTOI(tdvp);
3311 
3312 	/*
3313 	 * We only allow renaming of attributes from ATTRDIR to ATTRDIR.
3314 	 */
3315 	if ((tdp->i_mode & IFMT) != (sdp->i_mode & IFMT)) {
3316 		error = EINVAL;
3317 		goto unlock;
3318 	}
3319 
3320 	/*
3321 	 * Check accessibility of directory.
3322 	 */
3323 	if (error = ufs_diraccess(sdp, IEXEC, cr))
3324 		goto unlock;
3325 
3326 	/*
3327 	 * Look up inode of file we're supposed to rename.
3328 	 */
3329 	gethrestime(&now);
3330 	if (error = ufs_dirlook(sdp, snm, &sip, cr, 0, 0)) {
3331 		if (error == EAGAIN) {
3332 			if (ulp) {
3333 				TRANS_END_CSYNC(ufsvfsp, error, issync,
3334 				    TOP_RENAME, trans_size);
3335 				ufs_lockfs_end(ulp);
3336 			}
3337 			goto retry_rename;
3338 		}
3339 
3340 		goto unlock;
3341 	}
3342 
3343 	/*
3344 	 * Lock both the source and target directories (they may be
3345 	 * the same) to provide the atomicity semantics that was
3346 	 * previously provided by the per file system vfs_rename_lock
3347 	 *
3348 	 * with vfs_rename_lock removed to allow simultaneous renames
3349 	 * within a file system, ufs_dircheckpath can deadlock while
3350 	 * traversing back to ensure that source is not a parent directory
3351 	 * of target parent directory. This is because we get into
3352 	 * ufs_dircheckpath with the sdp and tdp locks held as RW_WRITER.
3353 	 * If the tdp and sdp of the simultaneous renames happen to be
3354 	 * in the path of each other, it can lead to a deadlock. This
3355 	 * can be avoided by getting the locks as RW_READER here and then
3356 	 * upgrading to RW_WRITER after completing the ufs_dircheckpath.
3357 	 *
3358 	 * We hold the target directory's i_rwlock after calling
3359 	 * ufs_lockfs_begin but in many other operations (like ufs_readdir)
3360 	 * VOP_RWLOCK is explicitly called by the filesystem independent code
3361 	 * before calling the file system operation. In these cases the order
3362 	 * is reversed (i.e i_rwlock is taken first and then ufs_lockfs_begin
3363 	 * is called). This is fine as long as ufs_lockfs_begin acts as a VOP
3364 	 * counter but with ufs_quiesce setting the SLOCK bit this becomes a
3365 	 * synchronizing object which might lead to a deadlock. So we use
3366 	 * rw_tryenter instead of rw_enter. If we fail to get this lock and
3367 	 * find that SLOCK bit is set, we call ufs_lockfs_end and restart the
3368 	 * operation.
3369 	 */
3370 retry:
3371 	first_lock = &tdp->i_rwlock;
3372 	second_lock = &sdp->i_rwlock;
3373 retry_firstlock:
3374 	if (!rw_tryenter(first_lock, RW_READER)) {
3375 		/*
3376 		 * We didn't get the lock. Check if the SLOCK is set in the
3377 		 * ufsvfs. If yes, we might be in a deadlock. Safer to give up
3378 		 * and wait for SLOCK to be cleared.
3379 		 */
3380 
3381 		if (ulp && ULOCKFS_IS_SLOCK(ulp)) {
3382 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME,
3383 			    trans_size);
3384 			ufs_lockfs_end(ulp);
3385 			goto retry_rename;
3386 
3387 		} else {
3388 			/*
3389 			 * SLOCK isn't set so this is a genuine synchronization
3390 			 * case. Let's try again after giving them a breather.
3391 			 */
3392 			delay(RETRY_LOCK_DELAY);
3393 			goto  retry_firstlock;
3394 		}
3395 	}
3396 	/*
3397 	 * Need to check if the tdp and sdp are same !!!
3398 	 */
3399 	if ((tdp != sdp) && (!rw_tryenter(second_lock, RW_READER))) {
3400 		/*
3401 		 * We didn't get the lock. Check if the SLOCK is set in the
3402 		 * ufsvfs. If yes, we might be in a deadlock. Safer to give up
3403 		 * and wait for SLOCK to be cleared.
3404 		 */
3405 
3406 		rw_exit(first_lock);
3407 		if (ulp && ULOCKFS_IS_SLOCK(ulp)) {
3408 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME,
3409 			    trans_size);
3410 			ufs_lockfs_end(ulp);
3411 			goto retry_rename;
3412 
3413 		} else {
3414 			/*
3415 			 * So we couldn't get the second level peer lock *and*
3416 			 * the SLOCK bit isn't set. Too bad we can be
3417 			 * contentding with someone wanting these locks otherway
3418 			 * round. Reverse the locks in case there is a heavy
3419 			 * contention for the second level lock.
3420 			 */
3421 			reverse_lock = first_lock;
3422 			first_lock = second_lock;
3423 			second_lock = reverse_lock;
3424 			ufs_rename_retry_cnt++;
3425 			goto  retry_firstlock;
3426 		}
3427 	}
3428 
3429 	if (sip == tdp) {
3430 		error = EINVAL;
3431 		goto errout;
3432 	}
3433 	/*
3434 	 * Make sure we can delete the source entry.  This requires
3435 	 * write permission on the containing directory.
3436 	 * Check for sticky directories.
3437 	 */
3438 	rw_enter(&sdp->i_contents, RW_READER);
3439 	rw_enter(&sip->i_contents, RW_READER);
3440 	if ((error = ufs_iaccess(sdp, IWRITE, cr, 0)) != 0 ||
3441 	    (error = ufs_sticky_remove_access(sdp, sip, cr)) != 0) {
3442 		rw_exit(&sip->i_contents);
3443 		rw_exit(&sdp->i_contents);
3444 		goto errout;
3445 	}
3446 
3447 	/*
3448 	 * If this is a rename of a directory and the parent is
3449 	 * different (".." must be changed), then the source
3450 	 * directory must not be in the directory hierarchy
3451 	 * above the target, as this would orphan everything
3452 	 * below the source directory.  Also the user must have
3453 	 * write permission in the source so as to be able to
3454 	 * change "..".
3455 	 */
3456 	if ((((sip->i_mode & IFMT) == IFDIR) ||
3457 	    ((sip->i_mode & IFMT) == IFATTRDIR)) && sdp != tdp) {
3458 		ino_t	inum;
3459 
3460 		if (error = ufs_iaccess(sip, IWRITE, cr, 0)) {
3461 			rw_exit(&sip->i_contents);
3462 			rw_exit(&sdp->i_contents);
3463 			goto errout;
3464 		}
3465 		inum = sip->i_number;
3466 		rw_exit(&sip->i_contents);
3467 		rw_exit(&sdp->i_contents);
3468 		if ((error = ufs_dircheckpath(inum, tdp, sdp, cr))) {
3469 			/*
3470 			 * If we got EAGAIN ufs_dircheckpath detected a
3471 			 * potential deadlock and backed out. We need
3472 			 * to retry the operation since sdp and tdp have
3473 			 * to be released to avoid the deadlock.
3474 			 */
3475 			if (error == EAGAIN) {
3476 				rw_exit(&tdp->i_rwlock);
3477 				if (tdp != sdp)
3478 					rw_exit(&sdp->i_rwlock);
3479 				delay(ufs_rename_backoff_delay);
3480 				ufs_rename_dircheck_retry_cnt++;
3481 				goto retry;
3482 			}
3483 			goto errout;
3484 		}
3485 	} else {
3486 		rw_exit(&sip->i_contents);
3487 		rw_exit(&sdp->i_contents);
3488 	}
3489 
3490 
3491 	/*
3492 	 * Check for renaming '.' or '..' or alias of '.'
3493 	 */
3494 	if (strcmp(snm, ".") == 0 || strcmp(snm, "..") == 0 || sdp == sip) {
3495 		error = EINVAL;
3496 		goto errout;
3497 	}
3498 
3499 	/*
3500 	 * Simultaneous renames can deadlock in ufs_dircheckpath since it
3501 	 * tries to traverse back the file tree with both tdp and sdp held
3502 	 * as RW_WRITER. To avoid that we have to hold the tdp and sdp locks
3503 	 * as RW_READERS  till ufs_dircheckpath is done.
3504 	 * Now that ufs_dircheckpath is done with, we can upgrade the locks
3505 	 * to RW_WRITER.
3506 	 */
3507 	if (!rw_tryupgrade(&tdp->i_rwlock)) {
3508 		/*
3509 		 * The upgrade failed. We got to give away the lock
3510 		 * as to avoid deadlocking with someone else who is
3511 		 * waiting for writer lock. With the lock gone, we
3512 		 * cannot be sure the checks done above will hold
3513 		 * good when we eventually get them back as writer.
3514 		 * So if we can't upgrade we drop the locks and retry
3515 		 * everything again.
3516 		 */
3517 		rw_exit(&tdp->i_rwlock);
3518 		if (tdp != sdp)
3519 			rw_exit(&sdp->i_rwlock);
3520 		delay(ufs_rename_backoff_delay);
3521 		ufs_rename_upgrade_retry_cnt++;
3522 		goto retry;
3523 	}
3524 	if (tdp != sdp) {
3525 		if (!rw_tryupgrade(&sdp->i_rwlock)) {
3526 			/*
3527 			 * The upgrade failed. We got to give away the lock
3528 			 * as to avoid deadlocking with someone else who is
3529 			 * waiting for writer lock. With the lock gone, we
3530 			 * cannot be sure the checks done above will hold
3531 			 * good when we eventually get them back as writer.
3532 			 * So if we can't upgrade we drop the locks and retry
3533 			 * everything again.
3534 			 */
3535 			rw_exit(&tdp->i_rwlock);
3536 			rw_exit(&sdp->i_rwlock);
3537 			delay(ufs_rename_backoff_delay);
3538 			ufs_rename_upgrade_retry_cnt++;
3539 			goto retry;
3540 		}
3541 	}
3542 
3543 	/*
3544 	 * Now that all the locks are held check to make sure another thread
3545 	 * didn't slip in and take out the sip.
3546 	 */
3547 	slot.status = NONE;
3548 	if ((sip->i_ctime.tv_usec * 1000) > now.tv_nsec ||
3549 	    sip->i_ctime.tv_sec > now.tv_sec) {
3550 		rw_enter(&sdp->i_ufsvfs->vfs_dqrwlock, RW_READER);
3551 		rw_enter(&sdp->i_contents, RW_WRITER);
3552 		error = ufs_dircheckforname(sdp, snm, strlen(snm), &slot,
3553 		    &ip, cr, 0);
3554 		rw_exit(&sdp->i_contents);
3555 		rw_exit(&sdp->i_ufsvfs->vfs_dqrwlock);
3556 		if (error) {
3557 			goto errout;
3558 		}
3559 		if (ip == NULL) {
3560 			error = ENOENT;
3561 			goto errout;
3562 		} else {
3563 			/*
3564 			 * If the inode was found need to drop the v_count
3565 			 * so as not to keep the filesystem from being
3566 			 * unmounted at a later time.
3567 			 */
3568 			VN_RELE(ITOV(ip));
3569 		}
3570 
3571 		/*
3572 		 * Release the slot.fbp that has the page mapped and
3573 		 * locked SE_SHARED, and could be used in in
3574 		 * ufs_direnter_lr() which needs to get the SE_EXCL lock
3575 		 * on said page.
3576 		 */
3577 		if (slot.fbp) {
3578 			fbrelse(slot.fbp, S_OTHER);
3579 			slot.fbp = NULL;
3580 		}
3581 	}
3582 
3583 	/*
3584 	 * Link source to the target.
3585 	 */
3586 	if (error = ufs_direnter_lr(tdp, tnm, DE_RENAME, sdp, sip, cr)) {
3587 		/*
3588 		 * ESAME isn't really an error; it indicates that the
3589 		 * operation should not be done because the source and target
3590 		 * are the same file, but that no error should be reported.
3591 		 */
3592 		if (error == ESAME)
3593 			error = 0;
3594 		goto errout;
3595 	}
3596 
3597 	if (error == 0 && tvp != NULL)
3598 		vnevent_rename_dest(tvp, tdvp, tnm, ct);
3599 
3600 	/*
3601 	 * Unlink the source.
3602 	 * Remove the source entry.  ufs_dirremove() checks that the entry
3603 	 * still reflects sip, and returns an error if it doesn't.
3604 	 * If the entry has changed just forget about it.  Release
3605 	 * the source inode.
3606 	 */
3607 	if ((error = ufs_dirremove(sdp, snm, sip, (struct vnode *)0,
3608 	    DR_RENAME, cr)) == ENOENT)
3609 		error = 0;
3610 
3611 	if (error == 0) {
3612 		vnevent_rename_src(ITOV(sip), sdvp, snm, ct);
3613 		/*
3614 		 * Notify the target directory of the rename event
3615 		 * if source and target directories are not the same.
3616 		 */
3617 		if (sdvp != tdvp)
3618 			vnevent_rename_dest_dir(tdvp, ct);
3619 	}
3620 
3621 errout:
3622 	if (slot.fbp)
3623 		fbrelse(slot.fbp, S_OTHER);
3624 
3625 	rw_exit(&tdp->i_rwlock);
3626 	if (sdp != tdp) {
3627 		rw_exit(&sdp->i_rwlock);
3628 	}
3629 
3630 unlock:
3631 	if (tvp != NULL)
3632 		VN_RELE(tvp);
3633 	if (sip != NULL)
3634 		VN_RELE(ITOV(sip));
3635 
3636 	if (ulp) {
3637 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME, trans_size);
3638 		ufs_lockfs_end(ulp);
3639 	}
3640 
3641 	return (error);
3642 }
3643 
3644 /*ARGSUSED*/
3645 static int
3646 ufs_mkdir(struct vnode *dvp, char *dirname, struct vattr *vap,
3647     struct vnode **vpp, struct cred *cr, caller_context_t *ct, int flags,
3648     vsecattr_t *vsecp)
3649 {
3650 	struct inode *ip;
3651 	struct inode *xip;
3652 	struct ufsvfs *ufsvfsp;
3653 	struct ulockfs *ulp;
3654 	int error;
3655 	int issync;
3656 	int trans_size;
3657 	int indeadlock;
3658 	int retry = 1;
3659 
3660 	ASSERT((vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));
3661 
3662 	/*
3663 	 * Can't make directory in attr hidden dir
3664 	 */
3665 	if ((VTOI(dvp)->i_mode & IFMT) == IFATTRDIR)
3666 		return (EINVAL);
3667 
3668 again:
3669 	ip = VTOI(dvp);
3670 	ufsvfsp = ip->i_ufsvfs;
3671 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_MKDIR_MASK);
3672 	if (error)
3673 		goto out;
3674 	if (ulp)
3675 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_MKDIR,
3676 		    trans_size = (int)TOP_MKDIR_SIZE(ip));
3677 
3678 	/*
3679 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3680 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3681 	 * possible, retries the operation.
3682 	 */
3683 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_MKDIR, retry);
3684 	if (indeadlock)
3685 		goto again;
3686 
3687 	error = ufs_direnter_cm(ip, dirname, DE_MKDIR, vap, &xip, cr,
3688 	    (retry ? IQUIET : 0));
3689 	if (error == EAGAIN) {
3690 		if (ulp) {
3691 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_MKDIR,
3692 			    trans_size);
3693 			ufs_lockfs_end(ulp);
3694 		}
3695 		goto again;
3696 	}
3697 
3698 	rw_exit(&ip->i_rwlock);
3699 	if (error == 0) {
3700 		ip = xip;
3701 		*vpp = ITOV(ip);
3702 	} else if (error == EEXIST)
3703 		VN_RELE(ITOV(xip));
3704 
3705 	if (ulp) {
3706 		int terr = 0;
3707 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_MKDIR, trans_size);
3708 		ufs_lockfs_end(ulp);
3709 		if (error == 0)
3710 			error = terr;
3711 	}
3712 out:
3713 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
3714 		ufs_delete_drain_wait(ufsvfsp, 1);
3715 		retry = 0;
3716 		goto again;
3717 	}
3718 
3719 	return (error);
3720 }
3721 
3722 /*ARGSUSED*/
3723 static int
3724 ufs_rmdir(struct vnode *vp, char *nm, struct vnode *cdir, struct cred *cr,
3725     caller_context_t *ct, int flags)
3726 {
3727 	struct inode *ip = VTOI(vp);
3728 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
3729 	struct ulockfs *ulp;
3730 	vnode_t *rmvp = NULL;	/* Vnode of removed directory */
3731 	int error;
3732 	int issync;
3733 	int trans_size;
3734 	int indeadlock;
3735 
3736 	/*
3737 	 * don't let the delete queue get too long
3738 	 */
3739 	if (ufsvfsp == NULL) {
3740 		error = EIO;
3741 		goto out;
3742 	}
3743 	if (ufsvfsp->vfs_delete.uq_ne > ufs_idle_max)
3744 		ufs_delete_drain(vp->v_vfsp, 1, 1);
3745 
3746 	error = ufs_eventlookup(vp, nm, cr, &rmvp);
3747 	if (rmvp != NULL) {
3748 		/* Only send the event if there were no errors */
3749 		if (error == 0)
3750 			vnevent_rmdir(rmvp, vp, nm, ct);
3751 		VN_RELE(rmvp);
3752 	}
3753 
3754 retry_rmdir:
3755 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_RMDIR_MASK);
3756 	if (error)
3757 		goto out;
3758 
3759 	if (ulp)
3760 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_RMDIR,
3761 		    trans_size = TOP_RMDIR_SIZE);
3762 
3763 	/*
3764 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3765 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3766 	 * possible, retries the operation.
3767 	 */
3768 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_RMDIR, retry);
3769 	if (indeadlock)
3770 		goto retry_rmdir;
3771 	error = ufs_dirremove(ip, nm, (struct inode *)0, cdir, DR_RMDIR, cr);
3772 
3773 	rw_exit(&ip->i_rwlock);
3774 
3775 	if (ulp) {
3776 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RMDIR,
3777 		    trans_size);
3778 		ufs_lockfs_end(ulp);
3779 	}
3780 
3781 out:
3782 	return (error);
3783 }
3784 
3785 /* ARGSUSED */
3786 static int
3787 ufs_readdir(struct vnode *vp, struct uio *uiop, struct cred *cr, int *eofp,
3788     caller_context_t *ct, int flags)
3789 {
3790 	struct iovec *iovp;
3791 	struct inode *ip;
3792 	struct direct *idp;
3793 	struct dirent64 *odp;
3794 	struct fbuf *fbp;
3795 	struct ufsvfs *ufsvfsp;
3796 	struct ulockfs *ulp;
3797 	caddr_t outbuf;
3798 	size_t bufsize;
3799 	uint_t offset;
3800 	uint_t bytes_wanted, total_bytes_wanted;
3801 	int incount = 0;
3802 	int outcount = 0;
3803 	int error;
3804 
3805 	ip = VTOI(vp);
3806 	ASSERT(RW_READ_HELD(&ip->i_rwlock));
3807 
3808 	if (uiop->uio_loffset >= MAXOFF32_T) {
3809 		if (eofp)
3810 			*eofp = 1;
3811 		return (0);
3812 	}
3813 
3814 	/*
3815 	 * Check if we have been called with a valid iov_len
3816 	 * and bail out if not, otherwise we may potentially loop
3817 	 * forever further down.
3818 	 */
3819 	if (uiop->uio_iov->iov_len <= 0) {
3820 		error = EINVAL;
3821 		goto out;
3822 	}
3823 
3824 	/*
3825 	 * Large Files: When we come here we are guaranteed that
3826 	 * uio_offset can be used safely. The high word is zero.
3827 	 */
3828 
3829 	ufsvfsp = ip->i_ufsvfs;
3830 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_READDIR_MASK);
3831 	if (error)
3832 		goto out;
3833 
3834 	iovp = uiop->uio_iov;
3835 	total_bytes_wanted = iovp->iov_len;
3836 
3837 	/* Large Files: directory files should not be "large" */
3838 
3839 	ASSERT(ip->i_size <= MAXOFF32_T);
3840 
3841 	/* Force offset to be valid (to guard against bogus lseek() values) */
3842 	offset = (uint_t)uiop->uio_offset & ~(DIRBLKSIZ - 1);
3843 
3844 	/* Quit if at end of file or link count of zero (posix) */
3845 	if (offset >= (uint_t)ip->i_size || ip->i_nlink <= 0) {
3846 		if (eofp)
3847 			*eofp = 1;
3848 		error = 0;
3849 		goto unlock;
3850 	}
3851 
3852 	/*
3853 	 * Get space to change directory entries into fs independent format.
3854 	 * Do fast alloc for the most commonly used-request size (filesystem
3855 	 * block size).
3856 	 */
3857 	if (uiop->uio_segflg != UIO_SYSSPACE || uiop->uio_iovcnt != 1) {
3858 		bufsize = total_bytes_wanted;
3859 		outbuf = kmem_alloc(bufsize, KM_SLEEP);
3860 		odp = (struct dirent64 *)outbuf;
3861 	} else {
3862 		bufsize = total_bytes_wanted;
3863 		odp = (struct dirent64 *)iovp->iov_base;
3864 	}
3865 
3866 nextblk:
3867 	bytes_wanted = total_bytes_wanted;
3868 
3869 	/* Truncate request to file size */
3870 	if (offset + bytes_wanted > (int)ip->i_size)
3871 		bytes_wanted = (int)(ip->i_size - offset);
3872 
3873 	/* Comply with MAXBSIZE boundary restrictions of fbread() */
3874 	if ((offset & MAXBOFFSET) + bytes_wanted > MAXBSIZE)
3875 		bytes_wanted = MAXBSIZE - (offset & MAXBOFFSET);
3876 
3877 	/*
3878 	 * Read in the next chunk.
3879 	 * We are still holding the i_rwlock.
3880 	 */
3881 	error = fbread(vp, (offset_t)offset, bytes_wanted, S_OTHER, &fbp);
3882 
3883 	if (error)
3884 		goto update_inode;
3885 	if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) && (ip->i_fs->fs_ronly == 0) &&
3886 	    (!ufsvfsp->vfs_noatime)) {
3887 		ip->i_flag |= IACC;
3888 	}
3889 	incount = 0;
3890 	idp = (struct direct *)fbp->fb_addr;
3891 	if (idp->d_ino == 0 && idp->d_reclen == 0 && idp->d_namlen == 0) {
3892 		cmn_err(CE_WARN, "ufs_readdir: bad dir, inumber = %llu, "
3893 		    "fs = %s\n",
3894 		    (u_longlong_t)ip->i_number, ufsvfsp->vfs_fs->fs_fsmnt);
3895 		fbrelse(fbp, S_OTHER);
3896 		error = ENXIO;
3897 		goto update_inode;
3898 	}
3899 	/* Transform to file-system independent format */
3900 	while (incount < bytes_wanted) {
3901 		/*
3902 		 * If the current directory entry is mangled, then skip
3903 		 * to the next block.  It would be nice to set the FSBAD
3904 		 * flag in the super-block so that a fsck is forced on
3905 		 * next reboot, but locking is a problem.
3906 		 */
3907 		if (idp->d_reclen & 0x3) {
3908 			offset = (offset + DIRBLKSIZ) & ~(DIRBLKSIZ-1);
3909 			break;
3910 		}
3911 
3912 		/* Skip to requested offset and skip empty entries */
3913 		if (idp->d_ino != 0 && offset >= (uint_t)uiop->uio_offset) {
3914 			ushort_t this_reclen =
3915 			    DIRENT64_RECLEN(idp->d_namlen);
3916 			/* Buffer too small for any entries */
3917 			if (!outcount && this_reclen > bufsize) {
3918 				fbrelse(fbp, S_OTHER);
3919 				error = EINVAL;
3920 				goto update_inode;
3921 			}
3922 			/* If would overrun the buffer, quit */
3923 			if (outcount + this_reclen > bufsize) {
3924 				break;
3925 			}
3926 			/* Take this entry */
3927 			odp->d_ino = (ino64_t)idp->d_ino;
3928 			odp->d_reclen = (ushort_t)this_reclen;
3929 			odp->d_off = (offset_t)(offset + idp->d_reclen);
3930 
3931 			/* use strncpy(9f) to zero out uninitialized bytes */
3932 
3933 			ASSERT(strlen(idp->d_name) + 1 <=
3934 			    DIRENT64_NAMELEN(this_reclen));
3935 			(void) strncpy(odp->d_name, idp->d_name,
3936 			    DIRENT64_NAMELEN(this_reclen));
3937 			outcount += odp->d_reclen;
3938 			odp = (struct dirent64 *)
3939 			    ((intptr_t)odp + odp->d_reclen);
3940 			ASSERT(outcount <= bufsize);
3941 		}
3942 		if (idp->d_reclen) {
3943 			incount += idp->d_reclen;
3944 			offset += idp->d_reclen;
3945 			idp = (struct direct *)((intptr_t)idp + idp->d_reclen);
3946 		} else {
3947 			offset = (offset + DIRBLKSIZ) & ~(DIRBLKSIZ-1);
3948 			break;
3949 		}
3950 	}
3951 	/* Release the chunk */
3952 	fbrelse(fbp, S_OTHER);
3953 
3954 	/* Read whole block, but got no entries, read another if not eof */
3955 
3956 	/*
3957 	 * Large Files: casting i_size to int here is not a problem
3958 	 * because directory sizes are always less than MAXOFF32_T.
3959 	 * See assertion above.
3960 	 */
3961 
3962 	if (offset < (int)ip->i_size && !outcount)
3963 		goto nextblk;
3964 
3965 	/* Copy out the entry data */
3966 	if (uiop->uio_segflg == UIO_SYSSPACE && uiop->uio_iovcnt == 1) {
3967 		iovp->iov_base += outcount;
3968 		iovp->iov_len -= outcount;
3969 		uiop->uio_resid -= outcount;
3970 		uiop->uio_offset = offset;
3971 	} else if ((error = uiomove(outbuf, (long)outcount, UIO_READ,
3972 	    uiop)) == 0)
3973 		uiop->uio_offset = offset;
3974 update_inode:
3975 	ITIMES(ip);
3976 	if (uiop->uio_segflg != UIO_SYSSPACE || uiop->uio_iovcnt != 1)
3977 		kmem_free(outbuf, bufsize);
3978 
3979 	if (eofp && error == 0)
3980 		*eofp = (uiop->uio_offset >= (int)ip->i_size);
3981 unlock:
3982 	if (ulp) {
3983 		ufs_lockfs_end(ulp);
3984 	}
3985 out:
3986 	return (error);
3987 }
3988 
3989 /*ARGSUSED*/
3990 static int
3991 ufs_symlink(struct vnode *dvp, char *linkname, struct vattr *vap, char *target,
3992     struct cred *cr, caller_context_t *ct, int flags)
3993 {
3994 	struct inode *ip, *dip = VTOI(dvp);
3995 	struct ufsvfs *ufsvfsp = dip->i_ufsvfs;
3996 	struct ulockfs *ulp;
3997 	int error;
3998 	int issync;
3999 	int trans_size;
4000 	int residual;
4001 	int ioflag;
4002 	int retry = 1;
4003 
4004 	/*
4005 	 * No symlinks in attrdirs at this time
4006 	 */
4007 	if ((VTOI(dvp)->i_mode & IFMT) == IFATTRDIR)
4008 		return (EINVAL);
4009 
4010 again:
4011 	ip = (struct inode *)NULL;
4012 	vap->va_type = VLNK;
4013 	vap->va_rdev = 0;
4014 
4015 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SYMLINK_MASK);
4016 	if (error)
4017 		goto out;
4018 
4019 	if (ulp)
4020 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_SYMLINK,
4021 		    trans_size = (int)TOP_SYMLINK_SIZE(dip));
4022 
4023 	/*
4024 	 * We must create the inode before the directory entry, to avoid
4025 	 * racing with readlink().  ufs_dirmakeinode requires that we
4026 	 * hold the quota lock as reader, and directory locks as writer.
4027 	 */
4028 
4029 	rw_enter(&dip->i_rwlock, RW_WRITER);
4030 	rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4031 	rw_enter(&dip->i_contents, RW_WRITER);
4032 
4033 	/*
4034 	 * Suppress any out of inodes messages if we will retry on
4035 	 * ENOSP
4036 	 */
4037 	if (retry)
4038 		dip->i_flag |= IQUIET;
4039 
4040 	error = ufs_dirmakeinode(dip, &ip, vap, DE_SYMLINK, cr);
4041 
4042 	dip->i_flag &= ~IQUIET;
4043 
4044 	rw_exit(&dip->i_contents);
4045 	rw_exit(&ufsvfsp->vfs_dqrwlock);
4046 	rw_exit(&dip->i_rwlock);
4047 
4048 	if (error)
4049 		goto unlock;
4050 
4051 	/*
4052 	 * OK.  The inode has been created.  Write out the data of the
4053 	 * symbolic link.  Since symbolic links are metadata, and should
4054 	 * remain consistent across a system crash, we need to force the
4055 	 * data out synchronously.
4056 	 *
4057 	 * (This is a change from the semantics in earlier releases, which
4058 	 * only created symbolic links synchronously if the semi-documented
4059 	 * 'syncdir' option was set, or if we were being invoked by the NFS
4060 	 * server, which requires symbolic links to be created synchronously.)
4061 	 *
4062 	 * We need to pass in a pointer for the residual length; otherwise
4063 	 * ufs_rdwri() will always return EIO if it can't write the data,
4064 	 * even if the error was really ENOSPC or EDQUOT.
4065 	 */
4066 
4067 	ioflag = FWRITE | FDSYNC;
4068 	residual = 0;
4069 
4070 	rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4071 	rw_enter(&ip->i_contents, RW_WRITER);
4072 
4073 	/*
4074 	 * Suppress file system full messages if we will retry
4075 	 */
4076 	if (retry)
4077 		ip->i_flag |= IQUIET;
4078 
4079 	error = ufs_rdwri(UIO_WRITE, ioflag, ip, target, strlen(target),
4080 	    (offset_t)0, UIO_SYSSPACE, &residual, cr);
4081 
4082 	ip->i_flag &= ~IQUIET;
4083 
4084 	if (error) {
4085 		rw_exit(&ip->i_contents);
4086 		rw_exit(&ufsvfsp->vfs_dqrwlock);
4087 		goto remove;
4088 	}
4089 
4090 	/*
4091 	 * If the link's data is small enough, we can cache it in the inode.
4092 	 * This is a "fast symbolic link".  We don't use the first direct
4093 	 * block because that's actually used to point at the symbolic link's
4094 	 * contents on disk; but we know that none of the other direct or
4095 	 * indirect blocks can be used because symbolic links are restricted
4096 	 * to be smaller than a file system block.
4097 	 */
4098 
4099 	ASSERT(MAXPATHLEN <= VBSIZE(ITOV(ip)));
4100 
4101 	if (ip->i_size > 0 && ip->i_size <= FSL_SIZE) {
4102 		if (kcopy(target, &ip->i_db[1], ip->i_size) == 0) {
4103 			ip->i_flag |= IFASTSYMLNK;
4104 		} else {
4105 			int i;
4106 			/* error, clear garbage left behind */
4107 			for (i = 1; i < NDADDR; i++)
4108 				ip->i_db[i] = 0;
4109 			for (i = 0; i < NIADDR; i++)
4110 				ip->i_ib[i] = 0;
4111 		}
4112 	}
4113 
4114 	rw_exit(&ip->i_contents);
4115 	rw_exit(&ufsvfsp->vfs_dqrwlock);
4116 
4117 	/*
4118 	 * OK.  We've successfully created the symbolic link.  All that
4119 	 * remains is to insert it into the appropriate directory.
4120 	 */
4121 
4122 	rw_enter(&dip->i_rwlock, RW_WRITER);
4123 	error = ufs_direnter_lr(dip, linkname, DE_SYMLINK, NULL, ip, cr);
4124 	rw_exit(&dip->i_rwlock);
4125 
4126 	/*
4127 	 * Fall through into remove-on-error code.  We're either done, or we
4128 	 * need to remove the inode (if we couldn't insert it).
4129 	 */
4130 
4131 remove:
4132 	if (error && (ip != NULL)) {
4133 		rw_enter(&ip->i_contents, RW_WRITER);
4134 		ip->i_nlink--;
4135 		ip->i_flag |= ICHG;
4136 		ip->i_seq++;
4137 		ufs_setreclaim(ip);
4138 		rw_exit(&ip->i_contents);
4139 	}
4140 
4141 unlock:
4142 	if (ip != NULL)
4143 		VN_RELE(ITOV(ip));
4144 
4145 	if (ulp) {
4146 		int terr = 0;
4147 
4148 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_SYMLINK,
4149 		    trans_size);
4150 		ufs_lockfs_end(ulp);
4151 		if (error == 0)
4152 			error = terr;
4153 	}
4154 
4155 	/*
4156 	 * We may have failed due to lack of an inode or of a block to
4157 	 * store the target in.  Try flushing the delete queue to free
4158 	 * logically-available things up and try again.
4159 	 */
4160 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
4161 		ufs_delete_drain_wait(ufsvfsp, 1);
4162 		retry = 0;
4163 		goto again;
4164 	}
4165 
4166 out:
4167 	return (error);
4168 }
4169 
4170 /*
4171  * Ufs specific routine used to do ufs io.
4172  */
4173 int
4174 ufs_rdwri(enum uio_rw rw, int ioflag, struct inode *ip, caddr_t base,
4175     ssize_t len, offset_t offset, enum uio_seg seg, int *aresid,
4176     struct cred *cr)
4177 {
4178 	struct uio auio;
4179 	struct iovec aiov;
4180 	int error;
4181 
4182 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
4183 
4184 	bzero((caddr_t)&auio, sizeof (uio_t));
4185 	bzero((caddr_t)&aiov, sizeof (iovec_t));
4186 
4187 	aiov.iov_base = base;
4188 	aiov.iov_len = len;
4189 	auio.uio_iov = &aiov;
4190 	auio.uio_iovcnt = 1;
4191 	auio.uio_loffset = offset;
4192 	auio.uio_segflg = (short)seg;
4193 	auio.uio_resid = len;
4194 
4195 	if (rw == UIO_WRITE) {
4196 		auio.uio_fmode = FWRITE;
4197 		auio.uio_extflg = UIO_COPY_DEFAULT;
4198 		auio.uio_llimit = curproc->p_fsz_ctl;
4199 		error = wrip(ip, &auio, ioflag, cr);
4200 	} else {
4201 		auio.uio_fmode = FREAD;
4202 		auio.uio_extflg = UIO_COPY_CACHED;
4203 		auio.uio_llimit = MAXOFFSET_T;
4204 		error = rdip(ip, &auio, ioflag, cr);
4205 	}
4206 
4207 	if (aresid) {
4208 		*aresid = auio.uio_resid;
4209 	} else if (auio.uio_resid) {
4210 		error = EIO;
4211 	}
4212 	return (error);
4213 }
4214 
4215 /*ARGSUSED*/
4216 static int
4217 ufs_fid(struct vnode *vp, struct fid *fidp, caller_context_t *ct)
4218 {
4219 	struct ufid *ufid;
4220 	struct inode *ip = VTOI(vp);
4221 
4222 	if (ip->i_ufsvfs == NULL)
4223 		return (EIO);
4224 
4225 	if (fidp->fid_len < (sizeof (struct ufid) - sizeof (ushort_t))) {
4226 		fidp->fid_len = sizeof (struct ufid) - sizeof (ushort_t);
4227 		return (ENOSPC);
4228 	}
4229 
4230 	ufid = (struct ufid *)fidp;
4231 	bzero((char *)ufid, sizeof (struct ufid));
4232 	ufid->ufid_len = sizeof (struct ufid) - sizeof (ushort_t);
4233 	ufid->ufid_ino = ip->i_number;
4234 	ufid->ufid_gen = ip->i_gen;
4235 
4236 	return (0);
4237 }
4238 
4239 /* ARGSUSED2 */
4240 static int
4241 ufs_rwlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
4242 {
4243 	struct inode	*ip = VTOI(vp);
4244 	struct ufsvfs	*ufsvfsp;
4245 	int		forcedirectio;
4246 
4247 	/*
4248 	 * Read case is easy.
4249 	 */
4250 	if (!write_lock) {
4251 		rw_enter(&ip->i_rwlock, RW_READER);
4252 		return (V_WRITELOCK_FALSE);
4253 	}
4254 
4255 	/*
4256 	 * Caller has requested a writer lock, but that inhibits any
4257 	 * concurrency in the VOPs that follow. Acquire the lock shared
4258 	 * and defer exclusive access until it is known to be needed in
4259 	 * other VOP handlers. Some cases can be determined here.
4260 	 */
4261 
4262 	/*
4263 	 * If directio is not set, there is no chance of concurrency,
4264 	 * so just acquire the lock exclusive. Beware of a forced
4265 	 * unmount before looking at the mount option.
4266 	 */
4267 	ufsvfsp = ip->i_ufsvfs;
4268 	forcedirectio = ufsvfsp ? ufsvfsp->vfs_forcedirectio : 0;
4269 	if (!(ip->i_flag & IDIRECTIO || forcedirectio) ||
4270 	    !ufs_allow_shared_writes) {
4271 		rw_enter(&ip->i_rwlock, RW_WRITER);
4272 		return (V_WRITELOCK_TRUE);
4273 	}
4274 
4275 	/*
4276 	 * Mandatory locking forces acquiring i_rwlock exclusive.
4277 	 */
4278 	if (MANDLOCK(vp, ip->i_mode)) {
4279 		rw_enter(&ip->i_rwlock, RW_WRITER);
4280 		return (V_WRITELOCK_TRUE);
4281 	}
4282 
4283 	/*
4284 	 * Acquire the lock shared in case a concurrent write follows.
4285 	 * Mandatory locking could have become enabled before the lock
4286 	 * was acquired. Re-check and upgrade if needed.
4287 	 */
4288 	rw_enter(&ip->i_rwlock, RW_READER);
4289 	if (MANDLOCK(vp, ip->i_mode)) {
4290 		rw_exit(&ip->i_rwlock);
4291 		rw_enter(&ip->i_rwlock, RW_WRITER);
4292 		return (V_WRITELOCK_TRUE);
4293 	}
4294 	return (V_WRITELOCK_FALSE);
4295 }
4296 
4297 /*ARGSUSED*/
4298 static void
4299 ufs_rwunlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
4300 {
4301 	struct inode	*ip = VTOI(vp);
4302 
4303 	rw_exit(&ip->i_rwlock);
4304 }
4305 
4306 /* ARGSUSED */
4307 static int
4308 ufs_seek(struct vnode *vp, offset_t ooff, offset_t *noffp, caller_context_t *ct)
4309 {
4310 	return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
4311 }
4312 
4313 /* ARGSUSED */
4314 static int
4315 ufs_frlock(struct vnode *vp, int cmd, struct flock64 *bfp, int flag,
4316     offset_t offset, struct flk_callback *flk_cbp, struct cred *cr,
4317     caller_context_t *ct)
4318 {
4319 	struct inode *ip = VTOI(vp);
4320 
4321 	if (ip->i_ufsvfs == NULL)
4322 		return (EIO);
4323 
4324 	/*
4325 	 * If file is being mapped, disallow frlock.
4326 	 * XXX I am not holding tlock while checking i_mapcnt because the
4327 	 * current locking strategy drops all locks before calling fs_frlock.
4328 	 * So, mapcnt could change before we enter fs_frlock making is
4329 	 * meaningless to have held tlock in the first place.
4330 	 */
4331 	if (ip->i_mapcnt > 0 && MANDLOCK(vp, ip->i_mode))
4332 		return (EAGAIN);
4333 	return (fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr, ct));
4334 }
4335 
4336 /* ARGSUSED */
4337 static int
4338 ufs_space(struct vnode *vp, int cmd, struct flock64 *bfp, int flag,
4339     offset_t offset, cred_t *cr, caller_context_t *ct)
4340 {
4341 	struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
4342 	struct ulockfs *ulp;
4343 	int error;
4344 
4345 	if ((error = convoff(vp, bfp, 0, offset)) == 0) {
4346 		if (cmd == F_FREESP) {
4347 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
4348 			    ULOCKFS_SPACE_MASK);
4349 			if (error)
4350 				return (error);
4351 			error = ufs_freesp(vp, bfp, flag, cr);
4352 
4353 			if (error == 0 && bfp->l_start == 0)
4354 				vnevent_truncate(vp, ct);
4355 		} else if (cmd == F_ALLOCSP) {
4356 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
4357 			    ULOCKFS_FALLOCATE_MASK);
4358 			if (error)
4359 				return (error);
4360 			error = ufs_allocsp(vp, bfp, cr);
4361 		} else
4362 			return (EINVAL); /* Command not handled here */
4363 
4364 		if (ulp)
4365 			ufs_lockfs_end(ulp);
4366 
4367 	}
4368 	return (error);
4369 }
4370 
4371 /*
4372  * Used to determine if read ahead should be done. Also used to
4373  * to determine when write back occurs.
4374  */
4375 #define	CLUSTSZ(ip)		((ip)->i_ufsvfs->vfs_ioclustsz)
4376 
4377 /*
4378  * A faster version of ufs_getpage.
4379  *
4380  * We optimize by inlining the pvn_getpages iterator, eliminating
4381  * calls to bmap_read if file doesn't have UFS holes, and avoiding
4382  * the overhead of page_exists().
4383  *
4384  * When files has UFS_HOLES and ufs_getpage is called with S_READ,
4385  * we set *protp to PROT_READ to avoid calling bmap_read. This approach
4386  * victimizes performance when a file with UFS holes is faulted
4387  * first in the S_READ mode, and then in the S_WRITE mode. We will get
4388  * two MMU faults in this case.
4389  *
4390  * XXX - the inode fields which control the sequential mode are not
4391  *	 protected by any mutex. The read ahead will act wild if
4392  *	 multiple processes will access the file concurrently and
4393  *	 some of them in sequential mode. One particulary bad case
4394  *	 is if another thread will change the value of i_nextrio between
4395  *	 the time this thread tests the i_nextrio value and then reads it
4396  *	 again to use it as the offset for the read ahead.
4397  */
4398 /*ARGSUSED*/
4399 static int
4400 ufs_getpage(struct vnode *vp, offset_t off, size_t len, uint_t *protp,
4401     page_t *plarr[], size_t plsz, struct seg *seg, caddr_t addr,
4402     enum seg_rw rw, struct cred *cr, caller_context_t *ct)
4403 {
4404 	u_offset_t	uoff = (u_offset_t)off; /* type conversion */
4405 	u_offset_t	pgoff;
4406 	u_offset_t	eoff;
4407 	struct inode	*ip = VTOI(vp);
4408 	struct ufsvfs	*ufsvfsp = ip->i_ufsvfs;
4409 	struct fs	*fs;
4410 	struct ulockfs	*ulp;
4411 	page_t		**pl;
4412 	caddr_t		pgaddr;
4413 	krw_t		rwtype;
4414 	int		err;
4415 	int		has_holes;
4416 	int		beyond_eof;
4417 	int		seqmode;
4418 	int		pgsize = PAGESIZE;
4419 	int		dolock;
4420 	int		do_qlock;
4421 	int		trans_size;
4422 
4423 	ASSERT((uoff & PAGEOFFSET) == 0);
4424 
4425 	if (protp)
4426 		*protp = PROT_ALL;
4427 
4428 	/*
4429 	 * Obey the lockfs protocol
4430 	 */
4431 	err = ufs_lockfs_begin_getpage(ufsvfsp, &ulp, seg,
4432 	    rw == S_READ || rw == S_EXEC, protp);
4433 	if (err)
4434 		goto out;
4435 
4436 	fs = ufsvfsp->vfs_fs;
4437 
4438 	if (ulp && (rw == S_CREATE || rw == S_WRITE) &&
4439 	    !(vp->v_flag & VISSWAP)) {
4440 		/*
4441 		 * Try to start a transaction, will return if blocking is
4442 		 * expected to occur and the address space is not the
4443 		 * kernel address space.
4444 		 */
4445 		trans_size = TOP_GETPAGE_SIZE(ip);
4446 		if (seg->s_as != &kas) {
4447 			TRANS_TRY_BEGIN_ASYNC(ufsvfsp, TOP_GETPAGE,
4448 			    trans_size, err)
4449 			if (err == EWOULDBLOCK) {
4450 				/*
4451 				 * Use EDEADLK here because the VM code
4452 				 * can normally never see this error.
4453 				 */
4454 				err = EDEADLK;
4455 				ufs_lockfs_end(ulp);
4456 				goto out;
4457 			}
4458 		} else {
4459 			TRANS_BEGIN_ASYNC(ufsvfsp, TOP_GETPAGE, trans_size);
4460 		}
4461 	}
4462 
4463 	if (vp->v_flag & VNOMAP) {
4464 		err = ENOSYS;
4465 		goto unlock;
4466 	}
4467 
4468 	seqmode = ip->i_nextr == uoff && rw != S_CREATE;
4469 
4470 	rwtype = RW_READER;		/* start as a reader */
4471 	dolock = (rw_owner(&ip->i_contents) != curthread);
4472 	/*
4473 	 * If this thread owns the lock, i.e., this thread grabbed it
4474 	 * as writer somewhere above, then we don't need to grab the
4475 	 * lock as reader in this routine.
4476 	 */
4477 	do_qlock = (rw_owner(&ufsvfsp->vfs_dqrwlock) != curthread);
4478 
4479 retrylock:
4480 	if (dolock) {
4481 		/*
4482 		 * Grab the quota lock if we need to call
4483 		 * bmap_write() below (with i_contents as writer).
4484 		 */
4485 		if (do_qlock && rwtype == RW_WRITER)
4486 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4487 		rw_enter(&ip->i_contents, rwtype);
4488 	}
4489 
4490 	/*
4491 	 * We may be getting called as a side effect of a bmap using
4492 	 * fbread() when the blocks might be being allocated and the
4493 	 * size has not yet been up'ed.  In this case we want to be
4494 	 * able to return zero pages if we get back UFS_HOLE from
4495 	 * calling bmap for a non write case here.  We also might have
4496 	 * to read some frags from the disk into a page if we are
4497 	 * extending the number of frags for a given lbn in bmap().
4498 	 * Large Files: The read of i_size here is atomic because
4499 	 * i_contents is held here. If dolock is zero, the lock
4500 	 * is held in bmap routines.
4501 	 */
4502 	beyond_eof = uoff + len >
4503 	    P2ROUNDUP_TYPED(ip->i_size, PAGESIZE, u_offset_t);
4504 	if (beyond_eof && seg != segkmap) {
4505 		if (dolock) {
4506 			rw_exit(&ip->i_contents);
4507 			if (do_qlock && rwtype == RW_WRITER)
4508 				rw_exit(&ufsvfsp->vfs_dqrwlock);
4509 		}
4510 		err = EFAULT;
4511 		goto unlock;
4512 	}
4513 
4514 	/*
4515 	 * Must hold i_contents lock throughout the call to pvn_getpages
4516 	 * since locked pages are returned from each call to ufs_getapage.
4517 	 * Must *not* return locked pages and then try for contents lock
4518 	 * due to lock ordering requirements (inode > page)
4519 	 */
4520 
4521 	has_holes = bmap_has_holes(ip);
4522 
4523 	if ((rw == S_WRITE || rw == S_CREATE) && has_holes && !beyond_eof) {
4524 		int	blk_size;
4525 		u_offset_t offset;
4526 
4527 		/*
4528 		 * We must acquire the RW_WRITER lock in order to
4529 		 * call bmap_write().
4530 		 */
4531 		if (dolock && rwtype == RW_READER) {
4532 			rwtype = RW_WRITER;
4533 
4534 			/*
4535 			 * Grab the quota lock before
4536 			 * upgrading i_contents, but if we can't grab it
4537 			 * don't wait here due to lock order:
4538 			 * vfs_dqrwlock > i_contents.
4539 			 */
4540 			if (do_qlock &&
4541 			    rw_tryenter(&ufsvfsp->vfs_dqrwlock, RW_READER)
4542 			    == 0) {
4543 				rw_exit(&ip->i_contents);
4544 				goto retrylock;
4545 			}
4546 			if (!rw_tryupgrade(&ip->i_contents)) {
4547 				rw_exit(&ip->i_contents);
4548 				if (do_qlock)
4549 					rw_exit(&ufsvfsp->vfs_dqrwlock);
4550 				goto retrylock;
4551 			}
4552 		}
4553 
4554 		/*
4555 		 * May be allocating disk blocks for holes here as
4556 		 * a result of mmap faults. write(2) does the bmap_write
4557 		 * in rdip/wrip, not here. We are not dealing with frags
4558 		 * in this case.
4559 		 */
4560 		/*
4561 		 * Large Files: We cast fs_bmask field to offset_t
4562 		 * just as we do for MAXBMASK because uoff is a 64-bit
4563 		 * data type. fs_bmask will still be a 32-bit type
4564 		 * as we cannot change any ondisk data structures.
4565 		 */
4566 
4567 		offset = uoff & (offset_t)fs->fs_bmask;
4568 		while (offset < uoff + len) {
4569 			blk_size = (int)blksize(fs, ip, lblkno(fs, offset));
4570 			err = bmap_write(ip, offset, blk_size,
4571 			    BI_NORMAL, NULL, cr);
4572 			if (ip->i_flag & (ICHG|IUPD))
4573 				ip->i_seq++;
4574 			if (err)
4575 				goto update_inode;
4576 			offset += blk_size; /* XXX - make this contig */
4577 		}
4578 	}
4579 
4580 	/*
4581 	 * Can be a reader from now on.
4582 	 */
4583 	if (dolock && rwtype == RW_WRITER) {
4584 		rw_downgrade(&ip->i_contents);
4585 		/*
4586 		 * We can release vfs_dqrwlock early so do it, but make
4587 		 * sure we don't try to release it again at the bottom.
4588 		 */
4589 		if (do_qlock) {
4590 			rw_exit(&ufsvfsp->vfs_dqrwlock);
4591 			do_qlock = 0;
4592 		}
4593 	}
4594 
4595 	/*
4596 	 * We remove PROT_WRITE in cases when the file has UFS holes
4597 	 * because we don't  want to call bmap_read() to check each
4598 	 * page if it is backed with a disk block.
4599 	 */
4600 	if (protp && has_holes && rw != S_WRITE && rw != S_CREATE)
4601 		*protp &= ~PROT_WRITE;
4602 
4603 	err = 0;
4604 
4605 	/*
4606 	 * The loop looks up pages in the range [off, off + len).
4607 	 * For each page, we first check if we should initiate an asynchronous
4608 	 * read ahead before we call page_lookup (we may sleep in page_lookup
4609 	 * for a previously initiated disk read).
4610 	 */
4611 	eoff = (uoff + len);
4612 	for (pgoff = uoff, pgaddr = addr, pl = plarr;
4613 	    pgoff < eoff; /* empty */) {
4614 		page_t	*pp;
4615 		u_offset_t	nextrio;
4616 		se_t	se;
4617 		int retval;
4618 
4619 		se = ((rw == S_CREATE || rw == S_OTHER) ? SE_EXCL : SE_SHARED);
4620 
4621 		/* Handle async getpage (faultahead) */
4622 		if (plarr == NULL) {
4623 			ip->i_nextrio = pgoff;
4624 			(void) ufs_getpage_ra(vp, pgoff, seg, pgaddr);
4625 			pgoff += pgsize;
4626 			pgaddr += pgsize;
4627 			continue;
4628 		}
4629 		/*
4630 		 * Check if we should initiate read ahead of next cluster.
4631 		 * We call page_exists only when we need to confirm that
4632 		 * we have the current page before we initiate the read ahead.
4633 		 */
4634 		nextrio = ip->i_nextrio;
4635 		if (seqmode &&
4636 		    pgoff + CLUSTSZ(ip) >= nextrio && pgoff <= nextrio &&
4637 		    nextrio < ip->i_size && page_exists(vp, pgoff)) {
4638 			retval = ufs_getpage_ra(vp, pgoff, seg, pgaddr);
4639 			/*
4640 			 * We always read ahead the next cluster of data
4641 			 * starting from i_nextrio. If the page (vp,nextrio)
4642 			 * is actually in core at this point, the routine
4643 			 * ufs_getpage_ra() will stop pre-fetching data
4644 			 * until we read that page in a synchronized manner
4645 			 * through ufs_getpage_miss(). So, we should increase
4646 			 * i_nextrio if the page (vp, nextrio) exists.
4647 			 */
4648 			if ((retval == 0) && page_exists(vp, nextrio)) {
4649 				ip->i_nextrio = nextrio + pgsize;
4650 			}
4651 		}
4652 
4653 		if ((pp = page_lookup(vp, pgoff, se)) != NULL) {
4654 			/*
4655 			 * We found the page in the page cache.
4656 			 */
4657 			*pl++ = pp;
4658 			pgoff += pgsize;
4659 			pgaddr += pgsize;
4660 			len -= pgsize;
4661 			plsz -= pgsize;
4662 		} else  {
4663 			/*
4664 			 * We have to create the page, or read it from disk.
4665 			 */
4666 			if (err = ufs_getpage_miss(vp, pgoff, len, seg, pgaddr,
4667 			    pl, plsz, rw, seqmode))
4668 				goto error;
4669 
4670 			while (*pl != NULL) {
4671 				pl++;
4672 				pgoff += pgsize;
4673 				pgaddr += pgsize;
4674 				len -= pgsize;
4675 				plsz -= pgsize;
4676 			}
4677 		}
4678 	}
4679 
4680 	/*
4681 	 * Return pages up to plsz if they are in the page cache.
4682 	 * We cannot return pages if there is a chance that they are
4683 	 * backed with a UFS hole and rw is S_WRITE or S_CREATE.
4684 	 */
4685 	if (plarr && !(has_holes && (rw == S_WRITE || rw == S_CREATE))) {
4686 
4687 		ASSERT((protp == NULL) ||
4688 		    !(has_holes && (*protp & PROT_WRITE)));
4689 
4690 		eoff = pgoff + plsz;
4691 		while (pgoff < eoff) {
4692 			page_t		*pp;
4693 
4694 			if ((pp = page_lookup_nowait(vp, pgoff,
4695 			    SE_SHARED)) == NULL)
4696 				break;
4697 
4698 			*pl++ = pp;
4699 			pgoff += pgsize;
4700 			plsz -= pgsize;
4701 		}
4702 	}
4703 
4704 	if (plarr)
4705 		*pl = NULL;			/* Terminate page list */
4706 	ip->i_nextr = pgoff;
4707 
4708 error:
4709 	if (err && plarr) {
4710 		/*
4711 		 * Release any pages we have locked.
4712 		 */
4713 		while (pl > &plarr[0])
4714 			page_unlock(*--pl);
4715 
4716 		plarr[0] = NULL;
4717 	}
4718 
4719 update_inode:
4720 	/*
4721 	 * If the inode is not already marked for IACC (in rdip() for read)
4722 	 * and the inode is not marked for no access time update (in wrip()
4723 	 * for write) then update the inode access time and mod time now.
4724 	 */
4725 	if ((ip->i_flag & (IACC | INOACC)) == 0) {
4726 		if ((rw != S_OTHER) && (ip->i_mode & IFMT) != IFDIR) {
4727 			if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) &&
4728 			    (fs->fs_ronly == 0) &&
4729 			    (!ufsvfsp->vfs_noatime)) {
4730 				mutex_enter(&ip->i_tlock);
4731 				ip->i_flag |= IACC;
4732 				ITIMES_NOLOCK(ip);
4733 				mutex_exit(&ip->i_tlock);
4734 			}
4735 		}
4736 	}
4737 
4738 	if (dolock) {
4739 		rw_exit(&ip->i_contents);
4740 		if (do_qlock && rwtype == RW_WRITER)
4741 			rw_exit(&ufsvfsp->vfs_dqrwlock);
4742 	}
4743 
4744 unlock:
4745 	if (ulp) {
4746 		if ((rw == S_CREATE || rw == S_WRITE) &&
4747 		    !(vp->v_flag & VISSWAP)) {
4748 			TRANS_END_ASYNC(ufsvfsp, TOP_GETPAGE, trans_size);
4749 		}
4750 		ufs_lockfs_end(ulp);
4751 	}
4752 out:
4753 	return (err);
4754 }
4755 
4756 /*
4757  * ufs_getpage_miss is called when ufs_getpage missed the page in the page
4758  * cache. The page is either read from the disk, or it's created.
4759  * A page is created (without disk read) if rw == S_CREATE, or if
4760  * the page is not backed with a real disk block (UFS hole).
4761  */
4762 /* ARGSUSED */
4763 static int
4764 ufs_getpage_miss(struct vnode *vp, u_offset_t off, size_t len, struct seg *seg,
4765     caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw, int seq)
4766 {
4767 	struct inode	*ip = VTOI(vp);
4768 	page_t		*pp;
4769 	daddr_t		bn;
4770 	size_t		io_len;
4771 	int		crpage = 0;
4772 	int		err;
4773 	int		contig;
4774 	int		bsize = ip->i_fs->fs_bsize;
4775 
4776 	/*
4777 	 * Figure out whether the page can be created, or must be
4778 	 * must be read from the disk.
4779 	 */
4780 	if (rw == S_CREATE)
4781 		crpage = 1;
4782 	else {
4783 		contig = 0;
4784 		if (err = bmap_read(ip, off, &bn, &contig))
4785 			return (err);
4786 
4787 		crpage = (bn == UFS_HOLE);
4788 
4789 		/*
4790 		 * If its also a fallocated block that hasn't been written to
4791 		 * yet, we will treat it just like a UFS_HOLE and create
4792 		 * a zero page for it
4793 		 */
4794 		if (ISFALLOCBLK(ip, bn))
4795 			crpage = 1;
4796 	}
4797 
4798 	if (crpage) {
4799 		if ((pp = page_create_va(vp, off, PAGESIZE, PG_WAIT, seg,
4800 		    addr)) == NULL) {
4801 			return (ufs_fault(vp,
4802 			    "ufs_getpage_miss: page_create == NULL"));
4803 		}
4804 
4805 		if (rw != S_CREATE)
4806 			pagezero(pp, 0, PAGESIZE);
4807 
4808 		io_len = PAGESIZE;
4809 	} else {
4810 		u_offset_t	io_off;
4811 		uint_t	xlen;
4812 		struct buf	*bp;
4813 		ufsvfs_t	*ufsvfsp = ip->i_ufsvfs;
4814 
4815 		/*
4816 		 * If access is not in sequential order, we read from disk
4817 		 * in bsize units.
4818 		 *
4819 		 * We limit the size of the transfer to bsize if we are reading
4820 		 * from the beginning of the file. Note in this situation we
4821 		 * will hedge our bets and initiate an async read ahead of
4822 		 * the second block.
4823 		 */
4824 		if (!seq || off == 0)
4825 			contig = MIN(contig, bsize);
4826 
4827 		pp = pvn_read_kluster(vp, off, seg, addr, &io_off,
4828 		    &io_len, off, contig, 0);
4829 
4830 		/*
4831 		 * Some other thread has entered the page.
4832 		 * ufs_getpage will retry page_lookup.
4833 		 */
4834 		if (pp == NULL) {
4835 			pl[0] = NULL;
4836 			return (0);
4837 		}
4838 
4839 		/*
4840 		 * Zero part of the page which we are not
4841 		 * going to read from the disk.
4842 		 */
4843 		xlen = io_len & PAGEOFFSET;
4844 		if (xlen != 0)
4845 			pagezero(pp->p_prev, xlen, PAGESIZE - xlen);
4846 
4847 		bp = pageio_setup(pp, io_len, ip->i_devvp, B_READ);
4848 		bp->b_edev = ip->i_dev;
4849 		bp->b_dev = cmpdev(ip->i_dev);
4850 		bp->b_blkno = bn;
4851 		bp->b_un.b_addr = (caddr_t)0;
4852 		bp->b_file = ip->i_vnode;
4853 		bp->b_offset = off;
4854 
4855 		if (ufsvfsp->vfs_log) {
4856 			lufs_read_strategy(ufsvfsp->vfs_log, bp);
4857 		} else if (ufsvfsp->vfs_snapshot) {
4858 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
4859 		} else {
4860 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
4861 			ub.ub_getpages.value.ul++;
4862 			(void) bdev_strategy(bp);
4863 			lwp_stat_update(LWP_STAT_INBLK, 1);
4864 		}
4865 
4866 		ip->i_nextrio = off + ((io_len + PAGESIZE - 1) & PAGEMASK);
4867 
4868 		/*
4869 		 * If the file access is sequential, initiate read ahead
4870 		 * of the next cluster.
4871 		 */
4872 		if (seq && ip->i_nextrio < ip->i_size)
4873 			(void) ufs_getpage_ra(vp, off, seg, addr);
4874 		err = biowait(bp);
4875 		pageio_done(bp);
4876 
4877 		if (err) {
4878 			pvn_read_done(pp, B_ERROR);
4879 			return (err);
4880 		}
4881 	}
4882 
4883 	pvn_plist_init(pp, pl, plsz, off, io_len, rw);
4884 	return (0);
4885 }
4886 
4887 /*
4888  * Read ahead a cluster from the disk. Returns the length in bytes.
4889  */
4890 static int
4891 ufs_getpage_ra(struct vnode *vp, u_offset_t off, struct seg *seg, caddr_t addr)
4892 {
4893 	struct inode	*ip = VTOI(vp);
4894 	page_t		*pp;
4895 	u_offset_t	io_off = ip->i_nextrio;
4896 	ufsvfs_t	*ufsvfsp;
4897 	caddr_t		addr2 = addr + (io_off - off);
4898 	struct buf	*bp;
4899 	daddr_t		bn;
4900 	size_t		io_len;
4901 	int		err;
4902 	int		contig;
4903 	int		xlen;
4904 	int		bsize = ip->i_fs->fs_bsize;
4905 
4906 	/*
4907 	 * If the directio advisory is in effect on this file,
4908 	 * then do not do buffered read ahead. Read ahead makes
4909 	 * it more difficult on threads using directio as they
4910 	 * will be forced to flush the pages from this vnode.
4911 	 */
4912 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
4913 		return (0);
4914 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio)
4915 		return (0);
4916 
4917 	/*
4918 	 * Is this test needed?
4919 	 */
4920 	if (addr2 >= seg->s_base + seg->s_size)
4921 		return (0);
4922 
4923 	contig = 0;
4924 	err = bmap_read(ip, io_off, &bn, &contig);
4925 	/*
4926 	 * If its a UFS_HOLE or a fallocated block, do not perform
4927 	 * any read ahead's since there probably is nothing to read ahead
4928 	 */
4929 	if (err || bn == UFS_HOLE || ISFALLOCBLK(ip, bn))
4930 		return (0);
4931 
4932 	/*
4933 	 * Limit the transfer size to bsize if this is the 2nd block.
4934 	 */
4935 	if (io_off == (u_offset_t)bsize)
4936 		contig = MIN(contig, bsize);
4937 
4938 	if ((pp = pvn_read_kluster(vp, io_off, seg, addr2, &io_off,
4939 	    &io_len, io_off, contig, 1)) == NULL)
4940 		return (0);
4941 
4942 	/*
4943 	 * Zero part of page which we are not going to read from disk
4944 	 */
4945 	if ((xlen = (io_len & PAGEOFFSET)) > 0)
4946 		pagezero(pp->p_prev, xlen, PAGESIZE - xlen);
4947 
4948 	ip->i_nextrio = (io_off + io_len + PAGESIZE - 1) & PAGEMASK;
4949 
4950 	bp = pageio_setup(pp, io_len, ip->i_devvp, B_READ | B_ASYNC);
4951 	bp->b_edev = ip->i_dev;
4952 	bp->b_dev = cmpdev(ip->i_dev);
4953 	bp->b_blkno = bn;
4954 	bp->b_un.b_addr = (caddr_t)0;
4955 	bp->b_file = ip->i_vnode;
4956 	bp->b_offset = off;
4957 
4958 	if (ufsvfsp->vfs_log) {
4959 		lufs_read_strategy(ufsvfsp->vfs_log, bp);
4960 	} else if (ufsvfsp->vfs_snapshot) {
4961 		fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
4962 	} else {
4963 		ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
4964 		ub.ub_getras.value.ul++;
4965 		(void) bdev_strategy(bp);
4966 		lwp_stat_update(LWP_STAT_INBLK, 1);
4967 	}
4968 
4969 	return (io_len);
4970 }
4971 
4972 int	ufs_delay = 1;
4973 /*
4974  * Flags are composed of {B_INVAL, B_FREE, B_DONTNEED, B_FORCE, B_ASYNC}
4975  *
4976  * LMXXX - the inode really ought to contain a pointer to one of these
4977  * async args.  Stuff gunk in there and just hand the whole mess off.
4978  * This would replace i_delaylen, i_delayoff.
4979  */
4980 /*ARGSUSED*/
4981 static int
4982 ufs_putpage(struct vnode *vp, offset_t off, size_t len, int flags,
4983     struct cred *cr, caller_context_t *ct)
4984 {
4985 	struct inode *ip = VTOI(vp);
4986 	int err = 0;
4987 
4988 	if (vp->v_count == 0) {
4989 		return (ufs_fault(vp, "ufs_putpage: bad v_count == 0"));
4990 	}
4991 
4992 	/*
4993 	 * XXX - Why should this check be made here?
4994 	 */
4995 	if (vp->v_flag & VNOMAP) {
4996 		err = ENOSYS;
4997 		goto errout;
4998 	}
4999 
5000 	if (ip->i_ufsvfs == NULL) {
5001 		err = EIO;
5002 		goto errout;
5003 	}
5004 
5005 	if (flags & B_ASYNC) {
5006 		if (ufs_delay && len &&
5007 		    (flags & ~(B_ASYNC|B_DONTNEED|B_FREE)) == 0) {
5008 			mutex_enter(&ip->i_tlock);
5009 			/*
5010 			 * If nobody stalled, start a new cluster.
5011 			 */
5012 			if (ip->i_delaylen == 0) {
5013 				ip->i_delayoff = off;
5014 				ip->i_delaylen = len;
5015 				mutex_exit(&ip->i_tlock);
5016 				goto errout;
5017 			}
5018 			/*
5019 			 * If we have a full cluster or they are not contig,
5020 			 * then push last cluster and start over.
5021 			 */
5022 			if (ip->i_delaylen >= CLUSTSZ(ip) ||
5023 			    ip->i_delayoff + ip->i_delaylen != off) {
5024 				u_offset_t doff;
5025 				size_t dlen;
5026 
5027 				doff = ip->i_delayoff;
5028 				dlen = ip->i_delaylen;
5029 				ip->i_delayoff = off;
5030 				ip->i_delaylen = len;
5031 				mutex_exit(&ip->i_tlock);
5032 				err = ufs_putpages(vp, doff, dlen,
5033 				    flags, cr);
5034 				/* LMXXX - flags are new val, not old */
5035 				goto errout;
5036 			}
5037 			/*
5038 			 * There is something there, it's not full, and
5039 			 * it is contig.
5040 			 */
5041 			ip->i_delaylen += len;
5042 			mutex_exit(&ip->i_tlock);
5043 			goto errout;
5044 		}
5045 		/*
5046 		 * Must have weird flags or we are not clustering.
5047 		 */
5048 	}
5049 
5050 	err = ufs_putpages(vp, off, len, flags, cr);
5051 
5052 errout:
5053 	return (err);
5054 }
5055 
5056 /*
5057  * If len == 0, do from off to EOF.
5058  *
5059  * The normal cases should be len == 0 & off == 0 (entire vp list),
5060  * len == MAXBSIZE (from segmap_release actions), and len == PAGESIZE
5061  * (from pageout).
5062  */
5063 /*ARGSUSED*/
5064 static int
5065 ufs_putpages(struct vnode *vp, offset_t off, size_t len, int flags,
5066     struct cred *cr)
5067 {
5068 	u_offset_t io_off;
5069 	u_offset_t eoff;
5070 	struct inode *ip = VTOI(vp);
5071 	page_t *pp;
5072 	size_t io_len;
5073 	int err = 0;
5074 	int dolock;
5075 
5076 	if (vp->v_count == 0)
5077 		return (ufs_fault(vp, "ufs_putpages: v_count == 0"));
5078 	/*
5079 	 * Acquire the readers/write inode lock before locking
5080 	 * any pages in this inode.
5081 	 * The inode lock is held during i/o.
5082 	 */
5083 	if (len == 0) {
5084 		mutex_enter(&ip->i_tlock);
5085 		ip->i_delayoff = ip->i_delaylen = 0;
5086 		mutex_exit(&ip->i_tlock);
5087 	}
5088 	dolock = (rw_owner(&ip->i_contents) != curthread);
5089 	if (dolock) {
5090 		/*
5091 		 * Must synchronize this thread and any possible thread
5092 		 * operating in the window of vulnerability in wrip().
5093 		 * It is dangerous to allow both a thread doing a putpage
5094 		 * and a thread writing, so serialize them.  The exception
5095 		 * is when the thread in wrip() does something which causes
5096 		 * a putpage operation.  Then, the thread must be allowed
5097 		 * to continue.  It may encounter a bmap_read problem in
5098 		 * ufs_putapage, but that is handled in ufs_putapage.
5099 		 * Allow async writers to proceed, we don't want to block
5100 		 * the pageout daemon.
5101 		 */
5102 		if (ip->i_writer == curthread)
5103 			rw_enter(&ip->i_contents, RW_READER);
5104 		else {
5105 			for (;;) {
5106 				rw_enter(&ip->i_contents, RW_READER);
5107 				mutex_enter(&ip->i_tlock);
5108 				/*
5109 				 * If there is no thread in the critical
5110 				 * section of wrip(), then proceed.
5111 				 * Otherwise, wait until there isn't one.
5112 				 */
5113 				if (ip->i_writer == NULL) {
5114 					mutex_exit(&ip->i_tlock);
5115 					break;
5116 				}
5117 				rw_exit(&ip->i_contents);
5118 				/*
5119 				 * Bounce async writers when we have a writer
5120 				 * working on this file so we don't deadlock
5121 				 * the pageout daemon.
5122 				 */
5123 				if (flags & B_ASYNC) {
5124 					mutex_exit(&ip->i_tlock);
5125 					return (0);
5126 				}
5127 				cv_wait(&ip->i_wrcv, &ip->i_tlock);
5128 				mutex_exit(&ip->i_tlock);
5129 			}
5130 		}
5131 	}
5132 
5133 	if (!vn_has_cached_data(vp)) {
5134 		if (dolock)
5135 			rw_exit(&ip->i_contents);
5136 		return (0);
5137 	}
5138 
5139 	if (len == 0) {
5140 		/*
5141 		 * Search the entire vp list for pages >= off.
5142 		 */
5143 		err = pvn_vplist_dirty(vp, (u_offset_t)off, ufs_putapage,
5144 		    flags, cr);
5145 	} else {
5146 		/*
5147 		 * Loop over all offsets in the range looking for
5148 		 * pages to deal with.
5149 		 */
5150 		if ((eoff = blkroundup(ip->i_fs, ip->i_size)) != 0)
5151 			eoff = MIN(off + len, eoff);
5152 		else
5153 			eoff = off + len;
5154 
5155 		for (io_off = off; io_off < eoff; io_off += io_len) {
5156 			/*
5157 			 * If we are not invalidating, synchronously
5158 			 * freeing or writing pages, use the routine
5159 			 * page_lookup_nowait() to prevent reclaiming
5160 			 * them from the free list.
5161 			 */
5162 			if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) {
5163 				pp = page_lookup(vp, io_off,
5164 				    (flags & (B_INVAL | B_FREE)) ?
5165 				    SE_EXCL : SE_SHARED);
5166 			} else {
5167 				pp = page_lookup_nowait(vp, io_off,
5168 				    (flags & B_FREE) ? SE_EXCL : SE_SHARED);
5169 			}
5170 
5171 			if (pp == NULL || pvn_getdirty(pp, flags) == 0)
5172 				io_len = PAGESIZE;
5173 			else {
5174 				u_offset_t *io_offp = &io_off;
5175 
5176 				err = ufs_putapage(vp, pp, io_offp, &io_len,
5177 				    flags, cr);
5178 				if (err != 0)
5179 					break;
5180 				/*
5181 				 * "io_off" and "io_len" are returned as
5182 				 * the range of pages we actually wrote.
5183 				 * This allows us to skip ahead more quickly
5184 				 * since several pages may've been dealt
5185 				 * with by this iteration of the loop.
5186 				 */
5187 			}
5188 		}
5189 	}
5190 	if (err == 0 && off == 0 && (len == 0 || len >= ip->i_size)) {
5191 		/*
5192 		 * We have just sync'ed back all the pages on
5193 		 * the inode, turn off the IMODTIME flag.
5194 		 */
5195 		mutex_enter(&ip->i_tlock);
5196 		ip->i_flag &= ~IMODTIME;
5197 		mutex_exit(&ip->i_tlock);
5198 	}
5199 	if (dolock)
5200 		rw_exit(&ip->i_contents);
5201 	return (err);
5202 }
5203 
5204 static int
5205 ufs_iodone(buf_t *bp)
5206 {
5207 	struct inode *ip;
5208 
5209 	ASSERT((bp->b_pages->p_vnode != NULL) && !(bp->b_flags & B_READ));
5210 
5211 	bp->b_iodone = NULL;
5212 
5213 	ip = VTOI(bp->b_pages->p_vnode);
5214 
5215 	mutex_enter(&ip->i_tlock);
5216 	if (ip->i_writes >= ufs_LW) {
5217 		if ((ip->i_writes -= bp->b_bcount) <= ufs_LW)
5218 			if (ufs_WRITES)
5219 				cv_broadcast(&ip->i_wrcv); /* wake all up */
5220 	} else {
5221 		ip->i_writes -= bp->b_bcount;
5222 	}
5223 
5224 	mutex_exit(&ip->i_tlock);
5225 	iodone(bp);
5226 	return (0);
5227 }
5228 
5229 /*
5230  * Write out a single page, possibly klustering adjacent
5231  * dirty pages.  The inode lock must be held.
5232  *
5233  * LMXXX - bsize < pagesize not done.
5234  */
5235 /*ARGSUSED*/
5236 int
5237 ufs_putapage(struct vnode *vp, page_t *pp, u_offset_t *offp, size_t *lenp,
5238     int flags, struct cred *cr)
5239 {
5240 	u_offset_t io_off;
5241 	u_offset_t off;
5242 	struct inode *ip = VTOI(vp);
5243 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
5244 	struct fs *fs;
5245 	struct buf *bp;
5246 	size_t io_len;
5247 	daddr_t bn;
5248 	int err;
5249 	int contig;
5250 	int dotrans;
5251 
5252 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
5253 
5254 	if (ufsvfsp == NULL) {
5255 		err = EIO;
5256 		goto out_trace;
5257 	}
5258 
5259 	fs = ip->i_fs;
5260 	ASSERT(fs->fs_ronly == 0);
5261 
5262 	/*
5263 	 * If the modified time on the inode has not already been
5264 	 * set elsewhere (e.g. for write/setattr) we set the time now.
5265 	 * This gives us approximate modified times for mmap'ed files
5266 	 * which are modified via stores in the user address space.
5267 	 */
5268 	if ((ip->i_flag & IMODTIME) == 0) {
5269 		mutex_enter(&ip->i_tlock);
5270 		ip->i_flag |= IUPD;
5271 		ip->i_seq++;
5272 		ITIMES_NOLOCK(ip);
5273 		mutex_exit(&ip->i_tlock);
5274 	}
5275 
5276 	/*
5277 	 * Align the request to a block boundry (for old file systems),
5278 	 * and go ask bmap() how contiguous things are for this file.
5279 	 */
5280 	off = pp->p_offset & (offset_t)fs->fs_bmask;	/* block align it */
5281 	contig = 0;
5282 	err = bmap_read(ip, off, &bn, &contig);
5283 	if (err)
5284 		goto out;
5285 	if (bn == UFS_HOLE) {			/* putpage never allocates */
5286 		/*
5287 		 * logging device is in error mode; simply return EIO
5288 		 */
5289 		if (TRANS_ISERROR(ufsvfsp)) {
5290 			err = EIO;
5291 			goto out;
5292 		}
5293 		/*
5294 		 * Oops, the thread in the window in wrip() did some
5295 		 * sort of operation which caused a putpage in the bad
5296 		 * range.  In this case, just return an error which will
5297 		 * cause the software modified bit on the page to set
5298 		 * and the page will get written out again later.
5299 		 */
5300 		if (ip->i_writer == curthread) {
5301 			err = EIO;
5302 			goto out;
5303 		}
5304 		/*
5305 		 * If the pager is trying to push a page in the bad range
5306 		 * just tell it to try again later when things are better.
5307 		 */
5308 		if (flags & B_ASYNC) {
5309 			err = EAGAIN;
5310 			goto out;
5311 		}
5312 		err = ufs_fault(ITOV(ip), "ufs_putapage: bn == UFS_HOLE");
5313 		goto out;
5314 	}
5315 
5316 	/*
5317 	 * If it is an fallocate'd block, reverse the negativity since
5318 	 * we are now writing to it
5319 	 */
5320 	if (ISFALLOCBLK(ip, bn)) {
5321 		err = bmap_set_bn(vp, off, dbtofsb(fs, -bn));
5322 		if (err)
5323 			goto out;
5324 
5325 		bn = -bn;
5326 	}
5327 
5328 	/*
5329 	 * Take the length (of contiguous bytes) passed back from bmap()
5330 	 * and _try_ and get a set of pages covering that extent.
5331 	 */
5332 	pp = pvn_write_kluster(vp, pp, &io_off, &io_len, off, contig, flags);
5333 
5334 	/*
5335 	 * May have run out of memory and not clustered backwards.
5336 	 * off		p_offset
5337 	 * [  pp - 1  ][   pp   ]
5338 	 * [	block		]
5339 	 * We told bmap off, so we have to adjust the bn accordingly.
5340 	 */
5341 	if (io_off > off) {
5342 		bn += btod(io_off - off);
5343 		contig -= (io_off - off);
5344 	}
5345 
5346 	/*
5347 	 * bmap was carefull to tell us the right size so use that.
5348 	 * There might be unallocated frags at the end.
5349 	 * LMXXX - bzero the end of the page?  We must be writing after EOF.
5350 	 */
5351 	if (io_len > contig) {
5352 		ASSERT(io_len - contig < fs->fs_bsize);
5353 		io_len -= (io_len - contig);
5354 	}
5355 
5356 	/*
5357 	 * Handle the case where we are writing the last page after EOF.
5358 	 *
5359 	 * XXX - just a patch for i-mt3.
5360 	 */
5361 	if (io_len == 0) {
5362 		ASSERT(pp->p_offset >=
5363 		    (u_offset_t)(roundup(ip->i_size, PAGESIZE)));
5364 		io_len = PAGESIZE;
5365 	}
5366 
5367 	bp = pageio_setup(pp, io_len, ip->i_devvp, B_WRITE | flags);
5368 
5369 	ULOCKFS_SET_MOD(ITOUL(ip));
5370 
5371 	bp->b_edev = ip->i_dev;
5372 	bp->b_dev = cmpdev(ip->i_dev);
5373 	bp->b_blkno = bn;
5374 	bp->b_un.b_addr = (caddr_t)0;
5375 	bp->b_file = ip->i_vnode;
5376 
5377 	/*
5378 	 * File contents of shadow or quota inodes are metadata, and updates
5379 	 * to these need to be put into a logging transaction. All direct
5380 	 * callers in UFS do that, but fsflush can come here _before_ the
5381 	 * normal codepath. An example would be updating ACL information, for
5382 	 * which the normal codepath would be:
5383 	 *	ufs_si_store()
5384 	 *	ufs_rdwri()
5385 	 *	wrip()
5386 	 *	segmap_release()
5387 	 *	VOP_PUTPAGE()
5388 	 * Here, fsflush can pick up the dirty page before segmap_release()
5389 	 * forces it out. If that happens, there's no transaction.
5390 	 * We therefore need to test whether a transaction exists, and if not
5391 	 * create one - for fsflush.
5392 	 */
5393 	dotrans =
5394 	    (((ip->i_mode & IFMT) == IFSHAD || ufsvfsp->vfs_qinod == ip) &&
5395 	    ((curthread->t_flag & T_DONTBLOCK) == 0) &&
5396 	    (TRANS_ISTRANS(ufsvfsp)));
5397 
5398 	if (dotrans) {
5399 		curthread->t_flag |= T_DONTBLOCK;
5400 		TRANS_BEGIN_ASYNC(ufsvfsp, TOP_PUTPAGE, TOP_PUTPAGE_SIZE(ip));
5401 	}
5402 	if (TRANS_ISTRANS(ufsvfsp)) {
5403 		if ((ip->i_mode & IFMT) == IFSHAD) {
5404 			TRANS_BUF(ufsvfsp, 0, io_len, bp, DT_SHAD);
5405 		} else if (ufsvfsp->vfs_qinod == ip) {
5406 			TRANS_DELTA(ufsvfsp, ldbtob(bn), bp->b_bcount, DT_QR,
5407 			    0, 0);
5408 		}
5409 	}
5410 	if (dotrans) {
5411 		TRANS_END_ASYNC(ufsvfsp, TOP_PUTPAGE, TOP_PUTPAGE_SIZE(ip));
5412 		curthread->t_flag &= ~T_DONTBLOCK;
5413 	}
5414 
5415 	/* write throttle */
5416 
5417 	ASSERT(bp->b_iodone == NULL);
5418 	bp->b_iodone = ufs_iodone;
5419 	mutex_enter(&ip->i_tlock);
5420 	ip->i_writes += bp->b_bcount;
5421 	mutex_exit(&ip->i_tlock);
5422 
5423 	if (bp->b_flags & B_ASYNC) {
5424 		if (ufsvfsp->vfs_log) {
5425 			lufs_write_strategy(ufsvfsp->vfs_log, bp);
5426 		} else if (ufsvfsp->vfs_snapshot) {
5427 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
5428 		} else {
5429 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5430 			ub.ub_putasyncs.value.ul++;
5431 			(void) bdev_strategy(bp);
5432 			lwp_stat_update(LWP_STAT_OUBLK, 1);
5433 		}
5434 	} else {
5435 		if (ufsvfsp->vfs_log) {
5436 			lufs_write_strategy(ufsvfsp->vfs_log, bp);
5437 		} else if (ufsvfsp->vfs_snapshot) {
5438 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
5439 		} else {
5440 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5441 			ub.ub_putsyncs.value.ul++;
5442 			(void) bdev_strategy(bp);
5443 			lwp_stat_update(LWP_STAT_OUBLK, 1);
5444 		}
5445 		err = biowait(bp);
5446 		pageio_done(bp);
5447 		pvn_write_done(pp, ((err) ? B_ERROR : 0) | B_WRITE | flags);
5448 	}
5449 
5450 	pp = NULL;
5451 
5452 out:
5453 	if (err != 0 && pp != NULL)
5454 		pvn_write_done(pp, B_ERROR | B_WRITE | flags);
5455 
5456 	if (offp)
5457 		*offp = io_off;
5458 	if (lenp)
5459 		*lenp = io_len;
5460 out_trace:
5461 	return (err);
5462 }
5463 
5464 uint64_t ufs_map_alock_retry_cnt;
5465 uint64_t ufs_map_lockfs_retry_cnt;
5466 
5467 /* ARGSUSED */
5468 static int
5469 ufs_map(struct vnode *vp, offset_t off, struct as *as, caddr_t *addrp,
5470     size_t len, uchar_t prot, uchar_t maxprot, uint_t flags, struct cred *cr,
5471     caller_context_t *ct)
5472 {
5473 	struct segvn_crargs vn_a;
5474 	struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
5475 	struct ulockfs *ulp;
5476 	int error, sig;
5477 	k_sigset_t smask;
5478 	caddr_t hint = *addrp;
5479 
5480 	if (vp->v_flag & VNOMAP) {
5481 		error = ENOSYS;
5482 		goto out;
5483 	}
5484 
5485 	if (off < (offset_t)0 || (offset_t)(off + len) < (offset_t)0) {
5486 		error = ENXIO;
5487 		goto out;
5488 	}
5489 
5490 	if (vp->v_type != VREG) {
5491 		error = ENODEV;
5492 		goto out;
5493 	}
5494 
5495 retry_map:
5496 	*addrp = hint;
5497 	/*
5498 	 * If file is being locked, disallow mapping.
5499 	 */
5500 	if (vn_has_mandatory_locks(vp, VTOI(vp)->i_mode)) {
5501 		error = EAGAIN;
5502 		goto out;
5503 	}
5504 
5505 	as_rangelock(as);
5506 	/*
5507 	 * Note that if we are retrying (because ufs_lockfs_trybegin failed in
5508 	 * the previous attempt), some other thread could have grabbed
5509 	 * the same VA range if MAP_FIXED is set. In that case, choose_addr
5510 	 * would unmap the valid VA range, that is ok.
5511 	 */
5512 	error = choose_addr(as, addrp, len, off, ADDR_VACALIGN, flags);
5513 	if (error != 0) {
5514 		as_rangeunlock(as);
5515 		goto out;
5516 	}
5517 
5518 	/*
5519 	 * a_lock has to be acquired before entering the lockfs protocol
5520 	 * because that is the order in which pagefault works. Also we cannot
5521 	 * block on a_lock here because this waiting writer will prevent
5522 	 * further readers like ufs_read from progressing and could cause
5523 	 * deadlock between ufs_read/ufs_map/pagefault when a quiesce is
5524 	 * pending.
5525 	 */
5526 	while (!AS_LOCK_TRYENTER(as, RW_WRITER)) {
5527 		ufs_map_alock_retry_cnt++;
5528 		delay(RETRY_LOCK_DELAY);
5529 	}
5530 
5531 	/*
5532 	 * We can't hold as->a_lock and wait for lockfs to succeed because
5533 	 * the proc tools might hang on a_lock, so call ufs_lockfs_trybegin()
5534 	 * instead.
5535 	 */
5536 	if (error = ufs_lockfs_trybegin(ufsvfsp, &ulp, ULOCKFS_MAP_MASK)) {
5537 		/*
5538 		 * ufs_lockfs_trybegin() did not succeed. It is safer to give up
5539 		 * as->a_lock and wait for ulp->ul_fs_lock status to change.
5540 		 */
5541 		ufs_map_lockfs_retry_cnt++;
5542 		AS_LOCK_EXIT(as);
5543 		as_rangeunlock(as);
5544 		if (error == EIO)
5545 			goto out;
5546 
5547 		mutex_enter(&ulp->ul_lock);
5548 		while (ulp->ul_fs_lock & ULOCKFS_MAP_MASK) {
5549 			if (ULOCKFS_IS_SLOCK(ulp) || ufsvfsp->vfs_nointr) {
5550 				cv_wait(&ulp->ul_cv, &ulp->ul_lock);
5551 			} else {
5552 				sigintr(&smask, 1);
5553 				sig = cv_wait_sig(&ulp->ul_cv, &ulp->ul_lock);
5554 				sigunintr(&smask);
5555 				if (((ulp->ul_fs_lock & ULOCKFS_MAP_MASK) &&
5556 				    !sig) || ufsvfsp->vfs_dontblock) {
5557 					mutex_exit(&ulp->ul_lock);
5558 					return (EINTR);
5559 				}
5560 			}
5561 		}
5562 		mutex_exit(&ulp->ul_lock);
5563 		goto retry_map;
5564 	}
5565 
5566 	vn_a.vp = vp;
5567 	vn_a.offset = (u_offset_t)off;
5568 	vn_a.type = flags & MAP_TYPE;
5569 	vn_a.prot = prot;
5570 	vn_a.maxprot = maxprot;
5571 	vn_a.cred = cr;
5572 	vn_a.amp = NULL;
5573 	vn_a.flags = flags & ~MAP_TYPE;
5574 	vn_a.szc = 0;
5575 	vn_a.lgrp_mem_policy_flags = 0;
5576 
5577 	error = as_map_locked(as, *addrp, len, segvn_create, &vn_a);
5578 	if (ulp)
5579 		ufs_lockfs_end(ulp);
5580 	as_rangeunlock(as);
5581 out:
5582 	return (error);
5583 }
5584 
5585 /* ARGSUSED */
5586 static int
5587 ufs_addmap(struct vnode *vp, offset_t off, struct as *as, caddr_t addr,
5588     size_t len, uchar_t  prot, uchar_t  maxprot, uint_t    flags,
5589     struct cred *cr, caller_context_t *ct)
5590 {
5591 	struct inode *ip = VTOI(vp);
5592 
5593 	if (vp->v_flag & VNOMAP) {
5594 		return (ENOSYS);
5595 	}
5596 
5597 	mutex_enter(&ip->i_tlock);
5598 	ip->i_mapcnt += btopr(len);
5599 	mutex_exit(&ip->i_tlock);
5600 	return (0);
5601 }
5602 
5603 /*ARGSUSED*/
5604 static int
5605 ufs_delmap(struct vnode *vp, offset_t off, struct as *as, caddr_t addr,
5606     size_t len, uint_t prot,  uint_t maxprot,  uint_t flags, struct cred *cr,
5607     caller_context_t *ct)
5608 {
5609 	struct inode *ip = VTOI(vp);
5610 
5611 	if (vp->v_flag & VNOMAP) {
5612 		return (ENOSYS);
5613 	}
5614 
5615 	mutex_enter(&ip->i_tlock);
5616 	ip->i_mapcnt -= btopr(len);	/* Count released mappings */
5617 	ASSERT(ip->i_mapcnt >= 0);
5618 	mutex_exit(&ip->i_tlock);
5619 	return (0);
5620 }
5621 /*
5622  * Return the answer requested to poll() for non-device files
5623  */
5624 struct pollhead ufs_pollhd;
5625 
5626 /* ARGSUSED */
5627 int
5628 ufs_poll(vnode_t *vp, short ev, int any, short *revp, struct pollhead **phpp,
5629     caller_context_t *ct)
5630 {
5631 	struct ufsvfs	*ufsvfsp;
5632 
5633 	/*
5634 	 * Regular files reject epollers (and edge-triggered pollers).
5635 	 * See the comment in fs_poll() for a more detailed explanation.
5636 	 */
5637 	if (fs_reject_epoll() || (ev & POLLET) != 0) {
5638 		return (EPERM);
5639 	}
5640 
5641 	*revp = 0;
5642 	ufsvfsp = VTOI(vp)->i_ufsvfs;
5643 
5644 	if (!ufsvfsp) {
5645 		*revp = POLLHUP;
5646 		goto out;
5647 	}
5648 
5649 	if (ULOCKFS_IS_HLOCK(&ufsvfsp->vfs_ulockfs) ||
5650 	    ULOCKFS_IS_ELOCK(&ufsvfsp->vfs_ulockfs)) {
5651 		*revp |= POLLERR;
5652 
5653 	} else {
5654 		if ((ev & POLLOUT) && !ufsvfsp->vfs_fs->fs_ronly &&
5655 		    !ULOCKFS_IS_WLOCK(&ufsvfsp->vfs_ulockfs))
5656 			*revp |= POLLOUT;
5657 
5658 		if ((ev & POLLWRBAND) && !ufsvfsp->vfs_fs->fs_ronly &&
5659 		    !ULOCKFS_IS_WLOCK(&ufsvfsp->vfs_ulockfs))
5660 			*revp |= POLLWRBAND;
5661 
5662 		if (ev & POLLIN)
5663 			*revp |= POLLIN;
5664 
5665 		if (ev & POLLRDNORM)
5666 			*revp |= POLLRDNORM;
5667 
5668 		if (ev & POLLRDBAND)
5669 			*revp |= POLLRDBAND;
5670 	}
5671 
5672 	if ((ev & POLLPRI) && (*revp & (POLLERR|POLLHUP)))
5673 		*revp |= POLLPRI;
5674 out:
5675 	if (*revp == 0 && ! any) {
5676 		*phpp = &ufs_pollhd;
5677 	}
5678 
5679 	return (0);
5680 }
5681 
5682 /* ARGSUSED */
5683 static int
5684 ufs_l_pathconf(struct vnode *vp, int cmd, ulong_t *valp, struct cred *cr,
5685     caller_context_t *ct)
5686 {
5687 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
5688 	struct ulockfs	*ulp = NULL;
5689 	struct inode	*sip = NULL;
5690 	int		error;
5691 	struct inode	*ip = VTOI(vp);
5692 	int		issync;
5693 
5694 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_PATHCONF_MASK);
5695 	if (error)
5696 		return (error);
5697 
5698 	switch (cmd) {
5699 		/*
5700 		 * Have to handle _PC_NAME_MAX here, because the normal way
5701 		 * [fs_pathconf() -> VOP_STATVFS() -> ufs_statvfs()]
5702 		 * results in a lock ordering reversal between
5703 		 * ufs_lockfs_{begin,end}() and
5704 		 * ufs_thread_{suspend,continue}().
5705 		 *
5706 		 * Keep in sync with ufs_statvfs().
5707 		 */
5708 	case _PC_NAME_MAX:
5709 		*valp = MAXNAMLEN;
5710 		break;
5711 
5712 	case _PC_FILESIZEBITS:
5713 		if (ufsvfsp->vfs_lfflags & UFS_LARGEFILES)
5714 			*valp = UFS_FILESIZE_BITS;
5715 		else
5716 			*valp = 32;
5717 		break;
5718 
5719 	case _PC_XATTR_EXISTS:
5720 		if (vp->v_vfsp->vfs_flag & VFS_XATTR) {
5721 
5722 			error =
5723 			    ufs_xattr_getattrdir(vp, &sip, LOOKUP_XATTR, cr);
5724 			if (error ==  0 && sip != NULL) {
5725 				/* Start transaction */
5726 				if (ulp) {
5727 					TRANS_BEGIN_CSYNC(ufsvfsp, issync,
5728 					    TOP_RMDIR, TOP_RMDIR_SIZE);
5729 				}
5730 				/*
5731 				 * Is directory empty
5732 				 */
5733 				rw_enter(&sip->i_rwlock, RW_WRITER);
5734 				rw_enter(&sip->i_contents, RW_WRITER);
5735 				if (ufs_xattrdirempty(sip,
5736 				    sip->i_number, CRED())) {
5737 					rw_enter(&ip->i_contents, RW_WRITER);
5738 					ufs_unhook_shadow(ip, sip);
5739 					rw_exit(&ip->i_contents);
5740 
5741 					*valp = 0;
5742 
5743 				} else
5744 					*valp = 1;
5745 				rw_exit(&sip->i_contents);
5746 				rw_exit(&sip->i_rwlock);
5747 				if (ulp) {
5748 					TRANS_END_CSYNC(ufsvfsp, error, issync,
5749 					    TOP_RMDIR, TOP_RMDIR_SIZE);
5750 				}
5751 				VN_RELE(ITOV(sip));
5752 			} else if (error == ENOENT) {
5753 				*valp = 0;
5754 				error = 0;
5755 			}
5756 		} else {
5757 			error = fs_pathconf(vp, cmd, valp, cr, ct);
5758 		}
5759 		break;
5760 
5761 	case _PC_ACL_ENABLED:
5762 		*valp = _ACL_ACLENT_ENABLED;
5763 		break;
5764 
5765 	case _PC_MIN_HOLE_SIZE:
5766 		*valp = (ulong_t)ip->i_fs->fs_bsize;
5767 		break;
5768 
5769 	case _PC_SATTR_ENABLED:
5770 	case _PC_SATTR_EXISTS:
5771 		*valp = vfs_has_feature(vp->v_vfsp, VFSFT_SYSATTR_VIEWS) &&
5772 		    (vp->v_type == VREG || vp->v_type == VDIR);
5773 		break;
5774 
5775 	case _PC_TIMESTAMP_RESOLUTION:
5776 		/*
5777 		 * UFS keeps only microsecond timestamp resolution.
5778 		 * This is historical and will probably never change.
5779 		 */
5780 		*valp = 1000L;
5781 		break;
5782 
5783 	default:
5784 		error = fs_pathconf(vp, cmd, valp, cr, ct);
5785 		break;
5786 	}
5787 
5788 	if (ulp != NULL) {
5789 		ufs_lockfs_end(ulp);
5790 	}
5791 	return (error);
5792 }
5793 
5794 int ufs_pageio_writes, ufs_pageio_reads;
5795 
5796 /*ARGSUSED*/
5797 static int
5798 ufs_pageio(struct vnode *vp, page_t *pp, u_offset_t io_off, size_t io_len,
5799     int flags, struct cred *cr, caller_context_t *ct)
5800 {
5801 	struct inode *ip = VTOI(vp);
5802 	struct ufsvfs *ufsvfsp;
5803 	page_t *npp = NULL, *opp = NULL, *cpp = pp;
5804 	struct buf *bp;
5805 	daddr_t bn;
5806 	size_t done_len = 0, cur_len = 0;
5807 	int err = 0;
5808 	int contig = 0;
5809 	int dolock;
5810 	int vmpss = 0;
5811 	struct ulockfs *ulp;
5812 
5813 	if ((flags & B_READ) && pp != NULL && pp->p_vnode == vp &&
5814 	    vp->v_mpssdata != NULL) {
5815 		vmpss = 1;
5816 	}
5817 
5818 	dolock = (rw_owner(&ip->i_contents) != curthread);
5819 	/*
5820 	 * We need a better check.  Ideally, we would use another
5821 	 * vnodeops so that hlocked and forcibly unmounted file
5822 	 * systems would return EIO where appropriate and w/o the
5823 	 * need for these checks.
5824 	 */
5825 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
5826 		return (EIO);
5827 
5828 	/*
5829 	 * For vmpss (pp can be NULL) case respect the quiesce protocol.
5830 	 * ul_lock must be taken before locking pages so we can't use it here
5831 	 * if pp is non NULL because segvn already locked pages
5832 	 * SE_EXCL. Instead we rely on the fact that a forced umount or
5833 	 * applying a filesystem lock via ufs_fiolfs() will block in the
5834 	 * implicit call to ufs_flush() until we unlock the pages after the
5835 	 * return to segvn. Other ufs_quiesce() callers keep ufs_quiesce_pend
5836 	 * above 0 until they are done. We have to be careful not to increment
5837 	 * ul_vnops_cnt here after forceful unmount hlocks the file system.
5838 	 *
5839 	 * If pp is NULL use ul_lock to make sure we don't increment
5840 	 * ul_vnops_cnt after forceful unmount hlocks the file system.
5841 	 */
5842 	if (vmpss || pp == NULL) {
5843 		ulp = &ufsvfsp->vfs_ulockfs;
5844 		if (pp == NULL)
5845 			mutex_enter(&ulp->ul_lock);
5846 		if (ulp->ul_fs_lock & ULOCKFS_GETREAD_MASK) {
5847 			if (pp == NULL) {
5848 				mutex_exit(&ulp->ul_lock);
5849 			}
5850 			return (vmpss ? EIO : EINVAL);
5851 		}
5852 		atomic_inc_ulong(&ulp->ul_vnops_cnt);
5853 		if (pp == NULL)
5854 			mutex_exit(&ulp->ul_lock);
5855 		if (ufs_quiesce_pend) {
5856 			if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
5857 				cv_broadcast(&ulp->ul_cv);
5858 			return (vmpss ? EIO : EINVAL);
5859 		}
5860 	}
5861 
5862 	if (dolock) {
5863 		/*
5864 		 * segvn may call VOP_PAGEIO() instead of VOP_GETPAGE() to
5865 		 * handle a fault against a segment that maps vnode pages with
5866 		 * large mappings.  Segvn creates pages and holds them locked
5867 		 * SE_EXCL during VOP_PAGEIO() call. In this case we have to
5868 		 * use rw_tryenter() to avoid a potential deadlock since in
5869 		 * lock order i_contents needs to be taken first.
5870 		 * Segvn will retry via VOP_GETPAGE() if VOP_PAGEIO() fails.
5871 		 */
5872 		if (!vmpss) {
5873 			rw_enter(&ip->i_contents, RW_READER);
5874 		} else if (!rw_tryenter(&ip->i_contents, RW_READER)) {
5875 			if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
5876 				cv_broadcast(&ulp->ul_cv);
5877 			return (EDEADLK);
5878 		}
5879 	}
5880 
5881 	/*
5882 	 * Return an error to segvn because the pagefault request is beyond
5883 	 * PAGESIZE rounded EOF.
5884 	 */
5885 	if (vmpss && btopr(io_off + io_len) > btopr(ip->i_size)) {
5886 		if (dolock)
5887 			rw_exit(&ip->i_contents);
5888 		if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
5889 			cv_broadcast(&ulp->ul_cv);
5890 		return (EFAULT);
5891 	}
5892 
5893 	if (pp == NULL) {
5894 		if (bmap_has_holes(ip)) {
5895 			err = ENOSYS;
5896 		} else {
5897 			err = EINVAL;
5898 		}
5899 		if (dolock)
5900 			rw_exit(&ip->i_contents);
5901 		if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
5902 			cv_broadcast(&ulp->ul_cv);
5903 		return (err);
5904 	}
5905 
5906 	/*
5907 	 * Break the io request into chunks, one for each contiguous
5908 	 * stretch of disk blocks in the target file.
5909 	 */
5910 	while (done_len < io_len) {
5911 		ASSERT(cpp);
5912 		contig = 0;
5913 		if (err = bmap_read(ip, (u_offset_t)(io_off + done_len),
5914 		    &bn, &contig))
5915 			break;
5916 
5917 		if (bn == UFS_HOLE) {	/* No holey swapfiles */
5918 			if (vmpss) {
5919 				err = EFAULT;
5920 				break;
5921 			}
5922 			err = ufs_fault(ITOV(ip), "ufs_pageio: bn == UFS_HOLE");
5923 			break;
5924 		}
5925 
5926 		cur_len = MIN(io_len - done_len, contig);
5927 		/*
5928 		 * Zero out a page beyond EOF, when the last block of
5929 		 * a file is a UFS fragment so that ufs_pageio() can be used
5930 		 * instead of ufs_getpage() to handle faults against
5931 		 * segvn segments that use large pages.
5932 		 */
5933 		page_list_break(&cpp, &npp, btopr(cur_len));
5934 		if ((flags & B_READ) && (cur_len & PAGEOFFSET)) {
5935 			size_t xlen = cur_len & PAGEOFFSET;
5936 			pagezero(cpp->p_prev, xlen, PAGESIZE - xlen);
5937 		}
5938 
5939 		bp = pageio_setup(cpp, cur_len, ip->i_devvp, flags);
5940 		ASSERT(bp != NULL);
5941 
5942 		bp->b_edev = ip->i_dev;
5943 		bp->b_dev = cmpdev(ip->i_dev);
5944 		bp->b_blkno = bn;
5945 		bp->b_un.b_addr = (caddr_t)0;
5946 		bp->b_file = ip->i_vnode;
5947 
5948 		ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5949 		ub.ub_pageios.value.ul++;
5950 		if (ufsvfsp->vfs_snapshot)
5951 			fssnap_strategy(&(ufsvfsp->vfs_snapshot), bp);
5952 		else
5953 			(void) bdev_strategy(bp);
5954 
5955 		if (flags & B_READ)
5956 			ufs_pageio_reads++;
5957 		else
5958 			ufs_pageio_writes++;
5959 		if (flags & B_READ)
5960 			lwp_stat_update(LWP_STAT_INBLK, 1);
5961 		else
5962 			lwp_stat_update(LWP_STAT_OUBLK, 1);
5963 		/*
5964 		 * If the request is not B_ASYNC, wait for i/o to complete
5965 		 * and re-assemble the page list to return to the caller.
5966 		 * If it is B_ASYNC we leave the page list in pieces and
5967 		 * cleanup() will dispose of them.
5968 		 */
5969 		if ((flags & B_ASYNC) == 0) {
5970 			err = biowait(bp);
5971 			pageio_done(bp);
5972 			if (err)
5973 				break;
5974 			page_list_concat(&opp, &cpp);
5975 		}
5976 		cpp = npp;
5977 		npp = NULL;
5978 		if (flags & B_READ)
5979 			cur_len = P2ROUNDUP_TYPED(cur_len, PAGESIZE, size_t);
5980 		done_len += cur_len;
5981 	}
5982 	ASSERT(err || (cpp == NULL && npp == NULL && done_len == io_len));
5983 	if (err) {
5984 		if (flags & B_ASYNC) {
5985 			/* Cleanup unprocessed parts of list */
5986 			page_list_concat(&cpp, &npp);
5987 			if (flags & B_READ)
5988 				pvn_read_done(cpp, B_ERROR);
5989 			else
5990 				pvn_write_done(cpp, B_ERROR);
5991 		} else {
5992 			/* Re-assemble list and let caller clean up */
5993 			page_list_concat(&opp, &cpp);
5994 			page_list_concat(&opp, &npp);
5995 		}
5996 	}
5997 
5998 	if (vmpss && !(ip->i_flag & IACC) && !ULOCKFS_IS_NOIACC(ulp) &&
5999 	    ufsvfsp->vfs_fs->fs_ronly == 0 && !ufsvfsp->vfs_noatime) {
6000 		mutex_enter(&ip->i_tlock);
6001 		ip->i_flag |= IACC;
6002 		ITIMES_NOLOCK(ip);
6003 		mutex_exit(&ip->i_tlock);
6004 	}
6005 
6006 	if (dolock)
6007 		rw_exit(&ip->i_contents);
6008 	if (vmpss && !atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
6009 		cv_broadcast(&ulp->ul_cv);
6010 	return (err);
6011 }
6012 
6013 /*
6014  * Called when the kernel is in a frozen state to dump data
6015  * directly to the device. It uses a private dump data structure,
6016  * set up by dump_ctl, to locate the correct disk block to which to dump.
6017  */
6018 /*ARGSUSED*/
6019 static int
6020 ufs_dump(vnode_t *vp, caddr_t addr, offset_t ldbn, offset_t dblks,
6021     caller_context_t *ct)
6022 {
6023 	u_offset_t	file_size;
6024 	struct inode    *ip = VTOI(vp);
6025 	struct fs	*fs = ip->i_fs;
6026 	daddr_t		dbn, lfsbn;
6027 	int		disk_blks = fs->fs_bsize >> DEV_BSHIFT;
6028 	int		error = 0;
6029 	int		ndbs, nfsbs;
6030 
6031 	/*
6032 	 * forced unmount case
6033 	 */
6034 	if (ip->i_ufsvfs == NULL)
6035 		return (EIO);
6036 	/*
6037 	 * Validate the inode that it has not been modified since
6038 	 * the dump structure is allocated.
6039 	 */
6040 	mutex_enter(&ip->i_tlock);
6041 	if ((dump_info == NULL) ||
6042 	    (dump_info->ip != ip) ||
6043 	    (dump_info->time.tv_sec != ip->i_mtime.tv_sec) ||
6044 	    (dump_info->time.tv_usec != ip->i_mtime.tv_usec)) {
6045 		mutex_exit(&ip->i_tlock);
6046 		return (-1);
6047 	}
6048 	mutex_exit(&ip->i_tlock);
6049 
6050 	/*
6051 	 * See that the file has room for this write
6052 	 */
6053 	UFS_GET_ISIZE(&file_size, ip);
6054 
6055 	if (ldbtob(ldbn + dblks) > file_size)
6056 		return (ENOSPC);
6057 
6058 	/*
6059 	 * Find the physical disk block numbers from the dump
6060 	 * private data structure directly and write out the data
6061 	 * in contiguous block lumps
6062 	 */
6063 	while (dblks > 0 && !error) {
6064 		lfsbn = (daddr_t)lblkno(fs, ldbtob(ldbn));
6065 		dbn = fsbtodb(fs, dump_info->dblk[lfsbn]) + ldbn % disk_blks;
6066 		nfsbs = 1;
6067 		ndbs = disk_blks - ldbn % disk_blks;
6068 		while (ndbs < dblks && fsbtodb(fs, dump_info->dblk[lfsbn +
6069 		    nfsbs]) == dbn + ndbs) {
6070 			nfsbs++;
6071 			ndbs += disk_blks;
6072 		}
6073 		if (ndbs > dblks)
6074 			ndbs = dblks;
6075 		error = bdev_dump(ip->i_dev, addr, dbn, ndbs);
6076 		addr += ldbtob((offset_t)ndbs);
6077 		dblks -= ndbs;
6078 		ldbn += ndbs;
6079 	}
6080 	return (error);
6081 
6082 }
6083 
6084 /*
6085  * Prepare the file system before and after the dump operation.
6086  *
6087  * action = DUMP_ALLOC:
6088  * Preparation before dump, allocate dump private data structure
6089  * to hold all the direct and indirect block info for dump.
6090  *
6091  * action = DUMP_FREE:
6092  * Clean up after dump, deallocate the dump private data structure.
6093  *
6094  * action = DUMP_SCAN:
6095  * Scan dump_info for *blkp DEV_BSIZE blocks of contig fs space;
6096  * if found, the starting file-relative DEV_BSIZE lbn is written
6097  * to *bklp; that lbn is intended for use with VOP_DUMP()
6098  */
6099 /*ARGSUSED*/
6100 static int
6101 ufs_dumpctl(vnode_t *vp, int action, offset_t *blkp, caller_context_t *ct)
6102 {
6103 	struct inode	*ip = VTOI(vp);
6104 	ufsvfs_t	*ufsvfsp = ip->i_ufsvfs;
6105 	struct fs	*fs;
6106 	daddr32_t	*dblk, *storeblk;
6107 	daddr32_t	*nextblk, *endblk;
6108 	struct buf	*bp;
6109 	int		i, entry, entries;
6110 	int		n, ncontig;
6111 
6112 	/*
6113 	 * check for forced unmount
6114 	 */
6115 	if (ufsvfsp == NULL)
6116 		return (EIO);
6117 
6118 	if (action == DUMP_ALLOC) {
6119 		/*
6120 		 * alloc and record dump_info
6121 		 */
6122 		if (dump_info != NULL)
6123 			return (EINVAL);
6124 
6125 		ASSERT(vp->v_type == VREG);
6126 		fs = ufsvfsp->vfs_fs;
6127 
6128 		rw_enter(&ip->i_contents, RW_READER);
6129 
6130 		if (bmap_has_holes(ip)) {
6131 			rw_exit(&ip->i_contents);
6132 			return (EFAULT);
6133 		}
6134 
6135 		/*
6136 		 * calculate and allocate space needed according to i_size
6137 		 */
6138 		entries = (int)lblkno(fs, blkroundup(fs, ip->i_size));
6139 		dump_info = kmem_alloc(sizeof (struct dump) +
6140 		    (entries - 1) * sizeof (daddr32_t), KM_NOSLEEP);
6141 		if (dump_info == NULL) {
6142 			rw_exit(&ip->i_contents);
6143 			return (ENOMEM);
6144 		}
6145 
6146 		/* Start saving the info */
6147 		dump_info->fsbs = entries;
6148 		dump_info->ip = ip;
6149 		storeblk = &dump_info->dblk[0];
6150 
6151 		/* Direct Blocks */
6152 		for (entry = 0; entry < NDADDR && entry < entries; entry++)
6153 			*storeblk++ = ip->i_db[entry];
6154 
6155 		/* Indirect Blocks */
6156 		for (i = 0; i < NIADDR; i++) {
6157 			int error = 0;
6158 
6159 			bp = UFS_BREAD(ufsvfsp,
6160 			    ip->i_dev, fsbtodb(fs, ip->i_ib[i]), fs->fs_bsize);
6161 			if (bp->b_flags & B_ERROR)
6162 				error = EIO;
6163 			else {
6164 				dblk = bp->b_un.b_daddr;
6165 				if ((storeblk = save_dblks(ip, ufsvfsp,
6166 				    storeblk, dblk, i, entries)) == NULL)
6167 					error = EIO;
6168 			}
6169 
6170 			brelse(bp);
6171 
6172 			if (error != 0) {
6173 				kmem_free(dump_info, sizeof (struct dump) +
6174 				    (entries - 1) * sizeof (daddr32_t));
6175 				rw_exit(&ip->i_contents);
6176 				dump_info = NULL;
6177 				return (error);
6178 			}
6179 		}
6180 		/* and time stamp the information */
6181 		mutex_enter(&ip->i_tlock);
6182 		dump_info->time = ip->i_mtime;
6183 		mutex_exit(&ip->i_tlock);
6184 
6185 		rw_exit(&ip->i_contents);
6186 	} else if (action == DUMP_FREE) {
6187 		/*
6188 		 * free dump_info
6189 		 */
6190 		if (dump_info == NULL)
6191 			return (EINVAL);
6192 		entries = dump_info->fsbs - 1;
6193 		kmem_free(dump_info, sizeof (struct dump) +
6194 		    entries * sizeof (daddr32_t));
6195 		dump_info = NULL;
6196 	} else if (action == DUMP_SCAN) {
6197 		/*
6198 		 * scan dump_info
6199 		 */
6200 		if (dump_info == NULL)
6201 			return (EINVAL);
6202 
6203 		dblk = dump_info->dblk;
6204 		nextblk = dblk + 1;
6205 		endblk = dblk + dump_info->fsbs - 1;
6206 		fs = ufsvfsp->vfs_fs;
6207 		ncontig = *blkp >> (fs->fs_bshift - DEV_BSHIFT);
6208 
6209 		/*
6210 		 * scan dblk[] entries; contig fs space is found when:
6211 		 * ((current blkno + frags per block) == next blkno)
6212 		 */
6213 		n = 0;
6214 		while (n < ncontig && dblk < endblk) {
6215 			if ((*dblk + fs->fs_frag) == *nextblk)
6216 				n++;
6217 			else
6218 				n = 0;
6219 			dblk++;
6220 			nextblk++;
6221 		}
6222 
6223 		/*
6224 		 * index is where size bytes of contig space begins;
6225 		 * conversion from index to the file's DEV_BSIZE lbn
6226 		 * is equivalent to:  (index * fs_bsize) / DEV_BSIZE
6227 		 */
6228 		if (n == ncontig) {
6229 			i = (dblk - dump_info->dblk) - ncontig;
6230 			*blkp = i << (fs->fs_bshift - DEV_BSHIFT);
6231 		} else
6232 			return (EFAULT);
6233 	}
6234 	return (0);
6235 }
6236 
6237 /*
6238  * Recursive helper function for ufs_dumpctl().  It follows the indirect file
6239  * system  blocks until it reaches the the disk block addresses, which are
6240  * then stored into the given buffer, storeblk.
6241  */
6242 static daddr32_t *
6243 save_dblks(struct inode *ip, struct ufsvfs *ufsvfsp,  daddr32_t *storeblk,
6244     daddr32_t *dblk, int level, int entries)
6245 {
6246 	struct fs	*fs = ufsvfsp->vfs_fs;
6247 	struct buf	*bp;
6248 	int		i;
6249 
6250 	if (level == 0) {
6251 		for (i = 0; i < NINDIR(fs); i++) {
6252 			if (storeblk - dump_info->dblk >= entries)
6253 				break;
6254 			*storeblk++ = dblk[i];
6255 		}
6256 		return (storeblk);
6257 	}
6258 	for (i = 0; i < NINDIR(fs); i++) {
6259 		if (storeblk - dump_info->dblk >= entries)
6260 			break;
6261 		bp = UFS_BREAD(ufsvfsp,
6262 		    ip->i_dev, fsbtodb(fs, dblk[i]), fs->fs_bsize);
6263 		if (bp->b_flags & B_ERROR) {
6264 			brelse(bp);
6265 			return (NULL);
6266 		}
6267 		storeblk = save_dblks(ip, ufsvfsp, storeblk, bp->b_un.b_daddr,
6268 		    level - 1, entries);
6269 		brelse(bp);
6270 
6271 		if (storeblk == NULL)
6272 			return (NULL);
6273 	}
6274 	return (storeblk);
6275 }
6276 
6277 /* ARGSUSED */
6278 static int
6279 ufs_getsecattr(struct vnode *vp, vsecattr_t *vsap, int flag,
6280     struct cred *cr, caller_context_t *ct)
6281 {
6282 	struct inode	*ip = VTOI(vp);
6283 	struct ulockfs	*ulp;
6284 	struct ufsvfs	*ufsvfsp = ip->i_ufsvfs;
6285 	ulong_t		vsa_mask = vsap->vsa_mask;
6286 	int		err = EINVAL;
6287 
6288 	vsa_mask &= (VSA_ACL | VSA_ACLCNT | VSA_DFACL | VSA_DFACLCNT);
6289 
6290 	/*
6291 	 * Only grab locks if needed - they're not needed to check vsa_mask
6292 	 * or if the mask contains no acl flags.
6293 	 */
6294 	if (vsa_mask != 0) {
6295 		if (err = ufs_lockfs_begin(ufsvfsp, &ulp,
6296 		    ULOCKFS_GETATTR_MASK))
6297 			return (err);
6298 
6299 		rw_enter(&ip->i_contents, RW_READER);
6300 		err = ufs_acl_get(ip, vsap, flag, cr);
6301 		rw_exit(&ip->i_contents);
6302 
6303 		if (ulp)
6304 			ufs_lockfs_end(ulp);
6305 	}
6306 	return (err);
6307 }
6308 
6309 /* ARGSUSED */
6310 static int
6311 ufs_setsecattr(struct vnode *vp, vsecattr_t *vsap, int flag, struct cred *cr,
6312     caller_context_t *ct)
6313 {
6314 	struct inode	*ip = VTOI(vp);
6315 	struct ulockfs	*ulp = NULL;
6316 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
6317 	ulong_t		vsa_mask = vsap->vsa_mask;
6318 	int		err;
6319 	int		haverwlock = 1;
6320 	int		trans_size;
6321 	int		donetrans = 0;
6322 	int		retry = 1;
6323 
6324 	ASSERT(RW_LOCK_HELD(&ip->i_rwlock));
6325 
6326 	/* Abort now if the request is either empty or invalid. */
6327 	vsa_mask &= (VSA_ACL | VSA_ACLCNT | VSA_DFACL | VSA_DFACLCNT);
6328 	if ((vsa_mask == 0) ||
6329 	    ((vsap->vsa_aclentp == NULL) &&
6330 	    (vsap->vsa_dfaclentp == NULL))) {
6331 		err = EINVAL;
6332 		goto out;
6333 	}
6334 
6335 	/*
6336 	 * Following convention, if this is a directory then we acquire the
6337 	 * inode's i_rwlock after starting a UFS logging transaction;
6338 	 * otherwise, we acquire it beforehand. Since we were called (and
6339 	 * must therefore return) with the lock held, we will have to drop it,
6340 	 * and later reacquire it, if operating on a directory.
6341 	 */
6342 	if (vp->v_type == VDIR) {
6343 		rw_exit(&ip->i_rwlock);
6344 		haverwlock = 0;
6345 	} else {
6346 		/* Upgrade the lock if required. */
6347 		if (!rw_write_held(&ip->i_rwlock)) {
6348 			rw_exit(&ip->i_rwlock);
6349 			rw_enter(&ip->i_rwlock, RW_WRITER);
6350 		}
6351 	}
6352 
6353 again:
6354 	ASSERT(!(vp->v_type == VDIR && haverwlock));
6355 	if (err = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SETATTR_MASK)) {
6356 		ulp = NULL;
6357 		retry = 0;
6358 		goto out;
6359 	}
6360 
6361 	/*
6362 	 * Check that the file system supports this operation. Note that
6363 	 * ufs_lockfs_begin() will have checked that the file system had
6364 	 * not been forcibly unmounted.
6365 	 */
6366 	if (ufsvfsp->vfs_fs->fs_ronly) {
6367 		err = EROFS;
6368 		goto out;
6369 	}
6370 	if (ufsvfsp->vfs_nosetsec) {
6371 		err = ENOSYS;
6372 		goto out;
6373 	}
6374 
6375 	if (ulp) {
6376 		TRANS_BEGIN_ASYNC(ufsvfsp, TOP_SETSECATTR,
6377 		    trans_size = TOP_SETSECATTR_SIZE(VTOI(vp)));
6378 		donetrans = 1;
6379 	}
6380 
6381 	if (vp->v_type == VDIR) {
6382 		rw_enter(&ip->i_rwlock, RW_WRITER);
6383 		haverwlock = 1;
6384 	}
6385 
6386 	ASSERT(haverwlock);
6387 
6388 	/* Do the actual work. */
6389 	rw_enter(&ip->i_contents, RW_WRITER);
6390 	/*
6391 	 * Suppress out of inodes messages if we will retry.
6392 	 */
6393 	if (retry)
6394 		ip->i_flag |= IQUIET;
6395 	err = ufs_acl_set(ip, vsap, flag, cr);
6396 	ip->i_flag &= ~IQUIET;
6397 	rw_exit(&ip->i_contents);
6398 
6399 out:
6400 	if (ulp) {
6401 		if (donetrans) {
6402 			/*
6403 			 * top_end_async() can eventually call
6404 			 * top_end_sync(), which can block. We must
6405 			 * therefore observe the lock-ordering protocol
6406 			 * here as well.
6407 			 */
6408 			if (vp->v_type == VDIR) {
6409 				rw_exit(&ip->i_rwlock);
6410 				haverwlock = 0;
6411 			}
6412 			TRANS_END_ASYNC(ufsvfsp, TOP_SETSECATTR, trans_size);
6413 		}
6414 		ufs_lockfs_end(ulp);
6415 	}
6416 	/*
6417 	 * If no inodes available, try scaring a logically-
6418 	 * free one out of the delete queue to someplace
6419 	 * that we can find it.
6420 	 */
6421 	if ((err == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
6422 		ufs_delete_drain_wait(ufsvfsp, 1);
6423 		retry = 0;
6424 		if (vp->v_type == VDIR && haverwlock) {
6425 			rw_exit(&ip->i_rwlock);
6426 			haverwlock = 0;
6427 		}
6428 		goto again;
6429 	}
6430 	/*
6431 	 * If we need to reacquire the lock then it is safe to do so
6432 	 * as a reader. This is because ufs_rwunlock(), which will be
6433 	 * called by our caller after we return, does not differentiate
6434 	 * between shared and exclusive locks.
6435 	 */
6436 	if (!haverwlock) {
6437 		ASSERT(vp->v_type == VDIR);
6438 		rw_enter(&ip->i_rwlock, RW_READER);
6439 	}
6440 
6441 	return (err);
6442 }
6443 
6444 /*
6445  * Locate the vnode to be used for an event notification. As this will
6446  * be called prior to the name space change perform basic verification
6447  * that the change will be allowed.
6448  */
6449 
6450 static int
6451 ufs_eventlookup(struct vnode *dvp, char *nm, struct cred *cr,
6452     struct vnode **vpp)
6453 {
6454 	int	namlen;
6455 	int	error;
6456 	struct vnode	*vp;
6457 	struct inode	*ip;
6458 	struct inode	*xip;
6459 	struct ufsvfs	*ufsvfsp;
6460 	struct ulockfs	*ulp;
6461 
6462 	ip = VTOI(dvp);
6463 	*vpp = NULL;
6464 
6465 	if ((namlen = strlen(nm)) == 0)
6466 		return (EINVAL);
6467 
6468 	if (nm[0] == '.') {
6469 		if (namlen == 1)
6470 			return (EINVAL);
6471 		else if ((namlen == 2) && nm[1] == '.') {
6472 			return (EEXIST);
6473 		}
6474 	}
6475 
6476 	/*
6477 	 * Check accessibility and write access of parent directory as we
6478 	 * only want to post the event if we're able to make a change.
6479 	 */
6480 	if (error = ufs_diraccess(ip, IEXEC|IWRITE, cr))
6481 		return (error);
6482 
6483 	if (vp = dnlc_lookup(dvp, nm)) {
6484 		if (vp == DNLC_NO_VNODE) {
6485 			VN_RELE(vp);
6486 			return (ENOENT);
6487 		}
6488 
6489 		*vpp = vp;
6490 		return (0);
6491 	}
6492 
6493 	/*
6494 	 * Keep the idle queue from getting too long by idling two
6495 	 * inodes before attempting to allocate another.
6496 	 * This operation must be performed before entering lockfs
6497 	 * or a transaction.
6498 	 */
6499 	if (ufs_idle_q.uq_ne > ufs_idle_q.uq_hiwat)
6500 		if ((curthread->t_flag & T_DONTBLOCK) == 0) {
6501 			ins.in_lidles.value.ul += ufs_lookup_idle_count;
6502 			ufs_idle_some(ufs_lookup_idle_count);
6503 		}
6504 
6505 	ufsvfsp = ip->i_ufsvfs;
6506 
6507 retry_lookup:
6508 	if (error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LOOKUP_MASK))
6509 		return (error);
6510 
6511 	if ((error = ufs_dirlook(ip, nm, &xip, cr, 1, 1)) == 0) {
6512 		vp = ITOV(xip);
6513 		*vpp = vp;
6514 	}
6515 
6516 	if (ulp) {
6517 		ufs_lockfs_end(ulp);
6518 	}
6519 
6520 	if (error == EAGAIN)
6521 		goto retry_lookup;
6522 
6523 	return (error);
6524 }
6525