xref: /titanic_41/usr/src/uts/common/fs/ufs/ufs_vnops.c (revision 93fb2a5ff9019dc98ff5e9836d0c2c7b5c5ecd7f)
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 (c) 2013, Joyent, Inc. All rights reserved.
25  */
26 
27 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #include <sys/types.h>
36 #include <sys/t_lock.h>
37 #include <sys/ksynch.h>
38 #include <sys/param.h>
39 #include <sys/time.h>
40 #include <sys/systm.h>
41 #include <sys/sysmacros.h>
42 #include <sys/resource.h>
43 #include <sys/signal.h>
44 #include <sys/cred.h>
45 #include <sys/user.h>
46 #include <sys/buf.h>
47 #include <sys/vfs.h>
48 #include <sys/vfs_opreg.h>
49 #include <sys/vnode.h>
50 #include <sys/proc.h>
51 #include <sys/disp.h>
52 #include <sys/file.h>
53 #include <sys/fcntl.h>
54 #include <sys/flock.h>
55 #include <sys/atomic.h>
56 #include <sys/kmem.h>
57 #include <sys/uio.h>
58 #include <sys/dnlc.h>
59 #include <sys/conf.h>
60 #include <sys/mman.h>
61 #include <sys/pathname.h>
62 #include <sys/debug.h>
63 #include <sys/vmsystm.h>
64 #include <sys/cmn_err.h>
65 #include <sys/filio.h>
66 #include <sys/policy.h>
67 
68 #include <sys/fs/ufs_fs.h>
69 #include <sys/fs/ufs_lockfs.h>
70 #include <sys/fs/ufs_filio.h>
71 #include <sys/fs/ufs_inode.h>
72 #include <sys/fs/ufs_fsdir.h>
73 #include <sys/fs/ufs_quota.h>
74 #include <sys/fs/ufs_log.h>
75 #include <sys/fs/ufs_snap.h>
76 #include <sys/fs/ufs_trans.h>
77 #include <sys/fs/ufs_panic.h>
78 #include <sys/fs/ufs_bio.h>
79 #include <sys/dirent.h>		/* must be AFTER <sys/fs/fsdir.h>! */
80 #include <sys/errno.h>
81 #include <sys/fssnap_if.h>
82 #include <sys/unistd.h>
83 #include <sys/sunddi.h>
84 
85 #include <sys/filio.h>		/* _FIOIO */
86 
87 #include <vm/hat.h>
88 #include <vm/page.h>
89 #include <vm/pvn.h>
90 #include <vm/as.h>
91 #include <vm/seg.h>
92 #include <vm/seg_map.h>
93 #include <vm/seg_vn.h>
94 #include <vm/seg_kmem.h>
95 #include <vm/rm.h>
96 #include <sys/swap.h>
97 
98 #include <fs/fs_subr.h>
99 
100 #include <sys/fs/decomp.h>
101 
102 static struct instats ins;
103 
104 static 	int ufs_getpage_ra(struct vnode *, u_offset_t, struct seg *, caddr_t);
105 static	int ufs_getpage_miss(struct vnode *, u_offset_t, size_t, struct seg *,
106 		caddr_t, struct page **, size_t, enum seg_rw, int);
107 static	int ufs_open(struct vnode **, int, struct cred *, caller_context_t *);
108 static	int ufs_close(struct vnode *, int, int, offset_t, struct cred *,
109 		caller_context_t *);
110 static	int ufs_read(struct vnode *, struct uio *, int, struct cred *,
111 		struct caller_context *);
112 static	int ufs_write(struct vnode *, struct uio *, int, struct cred *,
113 		struct caller_context *);
114 static	int ufs_ioctl(struct vnode *, int, intptr_t, int, struct cred *,
115 		int *, caller_context_t *);
116 static	int ufs_getattr(struct vnode *, struct vattr *, int, struct cred *,
117 		caller_context_t *);
118 static	int ufs_setattr(struct vnode *, struct vattr *, int, struct cred *,
119 		caller_context_t *);
120 static	int ufs_access(struct vnode *, int, int, struct cred *,
121 		caller_context_t *);
122 static	int ufs_lookup(struct vnode *, char *, struct vnode **,
123 		struct pathname *, int, struct vnode *, struct cred *,
124 		caller_context_t *, int *, pathname_t *);
125 static	int ufs_create(struct vnode *, char *, struct vattr *, enum vcexcl,
126 		int, struct vnode **, struct cred *, int,
127 		caller_context_t *, vsecattr_t  *);
128 static	int ufs_remove(struct vnode *, char *, struct cred *,
129 		caller_context_t *, int);
130 static	int ufs_link(struct vnode *, struct vnode *, char *, struct cred *,
131 		caller_context_t *, int);
132 static	int ufs_rename(struct vnode *, char *, struct vnode *, char *,
133 		struct cred *, caller_context_t *, int);
134 static	int ufs_mkdir(struct vnode *, char *, struct vattr *, struct vnode **,
135 		struct cred *, caller_context_t *, int, vsecattr_t *);
136 static	int ufs_rmdir(struct vnode *, char *, struct vnode *, struct cred *,
137 		caller_context_t *, int);
138 static	int ufs_readdir(struct vnode *, struct uio *, struct cred *, int *,
139 		caller_context_t *, int);
140 static	int ufs_symlink(struct vnode *, char *, struct vattr *, char *,
141 		struct cred *, caller_context_t *, int);
142 static	int ufs_readlink(struct vnode *, struct uio *, struct cred *,
143 		caller_context_t *);
144 static	int ufs_fsync(struct vnode *, int, struct cred *, caller_context_t *);
145 static	void ufs_inactive(struct vnode *, struct cred *, caller_context_t *);
146 static	int ufs_fid(struct vnode *, struct fid *, caller_context_t *);
147 static	int ufs_rwlock(struct vnode *, int, caller_context_t *);
148 static	void ufs_rwunlock(struct vnode *, int, caller_context_t *);
149 static	int ufs_seek(struct vnode *, offset_t, offset_t *, caller_context_t *);
150 static	int ufs_frlock(struct vnode *, int, struct flock64 *, int, offset_t,
151 		struct flk_callback *, struct cred *,
152 		caller_context_t *);
153 static  int ufs_space(struct vnode *, int, struct flock64 *, int, offset_t,
154 		cred_t *, caller_context_t *);
155 static	int ufs_getpage(struct vnode *, offset_t, size_t, uint_t *,
156 		struct page **, size_t, struct seg *, caddr_t,
157 		enum seg_rw, struct cred *, caller_context_t *);
158 static	int ufs_putpage(struct vnode *, offset_t, size_t, int, struct cred *,
159 		caller_context_t *);
160 static	int ufs_putpages(struct vnode *, offset_t, size_t, int, struct cred *);
161 static	int ufs_map(struct vnode *, offset_t, struct as *, caddr_t *, size_t,
162 		uchar_t, uchar_t, uint_t, struct cred *, caller_context_t *);
163 static	int ufs_addmap(struct vnode *, offset_t, struct as *, caddr_t,  size_t,
164 		uchar_t, uchar_t, uint_t, struct cred *, caller_context_t *);
165 static	int ufs_delmap(struct vnode *, offset_t, struct as *, caddr_t,  size_t,
166 		uint_t, uint_t, uint_t, struct cred *, caller_context_t *);
167 static	int ufs_poll(vnode_t *, short, int, short *, struct pollhead **,
168 		caller_context_t *);
169 static	int ufs_dump(vnode_t *, caddr_t, offset_t, offset_t,
170     caller_context_t *);
171 static	int ufs_l_pathconf(struct vnode *, int, ulong_t *, struct cred *,
172 		caller_context_t *);
173 static	int ufs_pageio(struct vnode *, struct page *, u_offset_t, size_t, int,
174 		struct cred *, caller_context_t *);
175 static	int ufs_dumpctl(vnode_t *, int, offset_t *, caller_context_t *);
176 static	daddr32_t *save_dblks(struct inode *, struct ufsvfs *, daddr32_t *,
177 		daddr32_t *, int, int);
178 static	int ufs_getsecattr(struct vnode *, vsecattr_t *, int, struct cred *,
179 		caller_context_t *);
180 static	int ufs_setsecattr(struct vnode *, vsecattr_t *, int, struct cred *,
181 		caller_context_t *);
182 static	int ufs_priv_access(void *, int, struct cred *);
183 static	int ufs_eventlookup(struct vnode *, char *, struct cred *,
184     struct vnode **);
185 extern int as_map_locked(struct as *, caddr_t, size_t, int ((*)()), void *);
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
ufs_open(struct vnode ** vpp,int flag,struct cred * cr,caller_context_t * ct)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
ufs_close(struct vnode * vp,int flag,int count,offset_t offset,struct cred * cr,caller_context_t * ct)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
ufs_read(struct vnode * vp,struct uio * uiop,int ioflag,struct cred * cr,struct caller_context * ct)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
ufs_check_rewrite(struct inode * ip,struct uio * uiop,int ioflag)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
ufs_write(struct vnode * vp,struct uio * uiop,int ioflag,cred_t * cr,caller_context_t * ct)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  * Free behind hacks.  The pager is busted.
662  * XXX - need to pass the information down to writedone() in a flag like B_SEQ
663  * or B_FREE_IF_TIGHT_ON_MEMORY.
664  */
665 int	freebehind = 1;
666 int	smallfile = 0;
667 u_offset_t smallfile64 = 32 * 1024;
668 
669 /*
670  * While we should, in most cases, cache the pages for write, we
671  * may also want to cache the pages for read as long as they are
672  * frequently re-usable.
673  *
674  * If cache_read_ahead = 1, the pages for read will go to the tail
675  * of the cache list when they are released, otherwise go to the head.
676  */
677 int	cache_read_ahead = 0;
678 
679 /*
680  * Freebehind exists  so that as we read  large files  sequentially we
681  * don't consume most of memory with pages  from a few files. It takes
682  * longer to re-read from disk multiple small files as it does reading
683  * one large one sequentially.  As system  memory grows customers need
684  * to retain bigger chunks   of files in  memory.   The advent of  the
685  * cachelist opens up of the possibility freeing pages  to the head or
686  * tail of the list.
687  *
688  * Not freeing a page is a bet that the page will be read again before
689  * it's segmap slot is needed for something else. If we loose the bet,
690  * it means some  other thread is  burdened with the  page free we did
691  * not do. If we win we save a free and reclaim.
692  *
693  * Freeing it at the tail  vs the head of cachelist  is a bet that the
694  * page will survive until the next  read.  It's also saying that this
695  * page is more likely to  be re-used than a  page freed some time ago
696  * and never reclaimed.
697  *
698  * Freebehind maintains a  range of  file offset [smallfile1; smallfile2]
699  *
700  *            0 < offset < smallfile1 : pages are not freed.
701  *   smallfile1 < offset < smallfile2 : pages freed to tail of cachelist.
702  *   smallfile2 < offset              : pages freed to head of cachelist.
703  *
704  * The range  is  computed  at most  once  per second  and  depends on
705  * freemem  and  ncpus_online.  Both parameters  are   bounded to be
706  * >= smallfile && >= smallfile64.
707  *
708  * smallfile1 = (free memory / ncpu) / 1000
709  * smallfile2 = (free memory / ncpu) / 10
710  *
711  * A few examples values:
712  *
713  *       Free Mem (in Bytes) [smallfile1; smallfile2]  [smallfile1; smallfile2]
714  *                                 ncpus_online = 4          ncpus_online = 64
715  *       ------------------  -----------------------   -----------------------
716  *             1G                   [256K;  25M]               [32K; 1.5M]
717  *            10G                   [2.5M; 250M]              [156K; 15M]
718  *           100G                    [25M; 2.5G]              [1.5M; 150M]
719  *
720  */
721 
722 #define	SMALLFILE1_D 1000
723 #define	SMALLFILE2_D 10
724 static u_offset_t smallfile1 = 32 * 1024;
725 static u_offset_t smallfile2 = 32 * 1024;
726 static clock_t smallfile_update = 0; /* lbolt value of when to recompute */
727 uint_t smallfile1_d = SMALLFILE1_D;
728 uint_t smallfile2_d = SMALLFILE2_D;
729 
730 /*
731  * wrip does the real work of write requests for ufs.
732  */
733 int
wrip(struct inode * ip,struct uio * uio,int ioflag,struct cred * cr)734 wrip(struct inode *ip, struct uio *uio, int ioflag, struct cred *cr)
735 {
736 	rlim64_t limit = uio->uio_llimit;
737 	u_offset_t off;
738 	u_offset_t old_i_size;
739 	struct fs *fs;
740 	struct vnode *vp;
741 	struct ufsvfs *ufsvfsp;
742 	caddr_t base;
743 	long start_resid = uio->uio_resid;	/* save starting resid */
744 	long premove_resid;			/* resid before uiomove() */
745 	uint_t flags;
746 	int newpage;
747 	int iupdat_flag, directio_status;
748 	int n, on, mapon;
749 	int error, pagecreate;
750 	int do_dqrwlock;		/* drop/reacquire vfs_dqrwlock */
751 	int32_t	iblocks;
752 	int	new_iblocks;
753 
754 	/*
755 	 * ip->i_size is incremented before the uiomove
756 	 * is done on a write.  If the move fails (bad user
757 	 * address) reset ip->i_size.
758 	 * The better way would be to increment ip->i_size
759 	 * only if the uiomove succeeds.
760 	 */
761 	int i_size_changed = 0;
762 	o_mode_t type;
763 	int i_seq_needed = 0;
764 
765 	vp = ITOV(ip);
766 
767 	/*
768 	 * check for forced unmount - should not happen as
769 	 * the request passed the lockfs checks.
770 	 */
771 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
772 		return (EIO);
773 
774 	fs = ip->i_fs;
775 
776 	ASSERT(RW_WRITE_HELD(&ip->i_contents));
777 
778 	/* check for valid filetype */
779 	type = ip->i_mode & IFMT;
780 	if ((type != IFREG) && (type != IFDIR) && (type != IFATTRDIR) &&
781 	    (type != IFLNK) && (type != IFSHAD)) {
782 		return (EIO);
783 	}
784 
785 	/*
786 	 * the actual limit of UFS file size
787 	 * is UFS_MAXOFFSET_T
788 	 */
789 	if (limit == RLIM64_INFINITY || limit > MAXOFFSET_T)
790 		limit = MAXOFFSET_T;
791 
792 	if (uio->uio_loffset >= limit) {
793 		proc_t *p = ttoproc(curthread);
794 
795 		mutex_enter(&p->p_lock);
796 		(void) rctl_action(rctlproc_legacy[RLIMIT_FSIZE], p->p_rctls,
797 		    p, RCA_UNSAFE_SIGINFO);
798 		mutex_exit(&p->p_lock);
799 		return (EFBIG);
800 	}
801 
802 	/*
803 	 * if largefiles are disallowed, the limit is
804 	 * the pre-largefiles value of 2GB
805 	 */
806 	if (ufsvfsp->vfs_lfflags & UFS_LARGEFILES)
807 		limit = MIN(UFS_MAXOFFSET_T, limit);
808 	else
809 		limit = MIN(MAXOFF32_T, limit);
810 
811 	if (uio->uio_loffset < (offset_t)0) {
812 		return (EINVAL);
813 	}
814 	if (uio->uio_resid == 0) {
815 		return (0);
816 	}
817 
818 	if (uio->uio_loffset >= limit)
819 		return (EFBIG);
820 
821 	ip->i_flag |= INOACC;	/* don't update ref time in getpage */
822 
823 	if (ioflag & (FSYNC|FDSYNC)) {
824 		ip->i_flag |= ISYNC;
825 		iupdat_flag = 1;
826 	}
827 	/*
828 	 * Try to go direct
829 	 */
830 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio) {
831 		uio->uio_llimit = limit;
832 		error = ufs_directio_write(ip, uio, ioflag, 0, cr,
833 		    &directio_status);
834 		/*
835 		 * If ufs_directio wrote to the file or set the flags,
836 		 * we need to update i_seq, but it may be deferred.
837 		 */
838 		if (start_resid != uio->uio_resid ||
839 		    (ip->i_flag & (ICHG|IUPD))) {
840 			i_seq_needed = 1;
841 			ip->i_flag |= ISEQ;
842 		}
843 		if (directio_status == DIRECTIO_SUCCESS)
844 			goto out;
845 	}
846 
847 	/*
848 	 * Behavior with respect to dropping/reacquiring vfs_dqrwlock:
849 	 *
850 	 * o shadow inodes: vfs_dqrwlock is not held at all
851 	 * o quota updates: vfs_dqrwlock is read or write held
852 	 * o other updates: vfs_dqrwlock is read held
853 	 *
854 	 * The first case is the only one where we do not hold
855 	 * vfs_dqrwlock at all while entering wrip().
856 	 * We must make sure not to downgrade/drop vfs_dqrwlock if we
857 	 * have it as writer, i.e. if we are updating the quota inode.
858 	 * There is no potential deadlock scenario in this case as
859 	 * ufs_getpage() takes care of this and avoids reacquiring
860 	 * vfs_dqrwlock in that case.
861 	 *
862 	 * This check is done here since the above conditions do not change
863 	 * and we possibly loop below, so save a few cycles.
864 	 */
865 	if ((type == IFSHAD) ||
866 	    (rw_owner(&ufsvfsp->vfs_dqrwlock) == curthread)) {
867 		do_dqrwlock = 0;
868 	} else {
869 		do_dqrwlock = 1;
870 	}
871 
872 	/*
873 	 * Large Files: We cast MAXBMASK to offset_t
874 	 * inorder to mask out the higher bits. Since offset_t
875 	 * is a signed value, the high order bit set in MAXBMASK
876 	 * value makes it do the right thing by having all bits 1
877 	 * in the higher word. May be removed for _SOLARIS64_.
878 	 */
879 
880 	fs = ip->i_fs;
881 	do {
882 		u_offset_t uoff = uio->uio_loffset;
883 		off = uoff & (offset_t)MAXBMASK;
884 		mapon = (int)(uoff & (offset_t)MAXBOFFSET);
885 		on = (int)blkoff(fs, uoff);
886 		n = (int)MIN(fs->fs_bsize - on, uio->uio_resid);
887 		new_iblocks = 1;
888 
889 		if (type == IFREG && uoff + n >= limit) {
890 			if (uoff >= limit) {
891 				error = EFBIG;
892 				goto out;
893 			}
894 			/*
895 			 * since uoff + n >= limit,
896 			 * therefore n >= limit - uoff, and n is an int
897 			 * so it is safe to cast it to an int
898 			 */
899 			n = (int)(limit - (rlim64_t)uoff);
900 		}
901 		if (uoff + n > ip->i_size) {
902 			/*
903 			 * We are extending the length of the file.
904 			 * bmap is used so that we are sure that
905 			 * if we need to allocate new blocks, that it
906 			 * is done here before we up the file size.
907 			 */
908 			error = bmap_write(ip, uoff, (int)(on + n),
909 			    mapon == 0, NULL, cr);
910 			/*
911 			 * bmap_write never drops i_contents so if
912 			 * the flags are set it changed the file.
913 			 */
914 			if (ip->i_flag & (ICHG|IUPD)) {
915 				i_seq_needed = 1;
916 				ip->i_flag |= ISEQ;
917 			}
918 			if (error)
919 				break;
920 			/*
921 			 * There is a window of vulnerability here.
922 			 * The sequence of operations: allocate file
923 			 * system blocks, uiomove the data into pages,
924 			 * and then update the size of the file in the
925 			 * inode, must happen atomically.  However, due
926 			 * to current locking constraints, this can not
927 			 * be done.
928 			 */
929 			ASSERT(ip->i_writer == NULL);
930 			ip->i_writer = curthread;
931 			i_size_changed = 1;
932 			/*
933 			 * If we are writing from the beginning of
934 			 * the mapping, we can just create the
935 			 * pages without having to read them.
936 			 */
937 			pagecreate = (mapon == 0);
938 		} else if (n == MAXBSIZE) {
939 			/*
940 			 * Going to do a whole mappings worth,
941 			 * so we can just create the pages w/o
942 			 * having to read them in.  But before
943 			 * we do that, we need to make sure any
944 			 * needed blocks are allocated first.
945 			 */
946 			iblocks = ip->i_blocks;
947 			error = bmap_write(ip, uoff, (int)(on + n),
948 			    BI_ALLOC_ONLY, NULL, cr);
949 			/*
950 			 * bmap_write never drops i_contents so if
951 			 * the flags are set it changed the file.
952 			 */
953 			if (ip->i_flag & (ICHG|IUPD)) {
954 				i_seq_needed = 1;
955 				ip->i_flag |= ISEQ;
956 			}
957 			if (error)
958 				break;
959 			pagecreate = 1;
960 			/*
961 			 * check if the new created page needed the
962 			 * allocation of new disk blocks.
963 			 */
964 			if (iblocks == ip->i_blocks)
965 				new_iblocks = 0; /* no new blocks allocated */
966 		} else {
967 			pagecreate = 0;
968 			/*
969 			 * In sync mode flush the indirect blocks which
970 			 * may have been allocated and not written on
971 			 * disk. In above cases bmap_write will allocate
972 			 * in sync mode.
973 			 */
974 			if (ioflag & (FSYNC|FDSYNC)) {
975 				error = ufs_indirblk_sync(ip, uoff);
976 				if (error)
977 					break;
978 			}
979 		}
980 
981 		/*
982 		 * At this point we can enter ufs_getpage() in one
983 		 * of two ways:
984 		 * 1) segmap_getmapflt() calls ufs_getpage() when the
985 		 *    forcefault parameter is true (pagecreate == 0)
986 		 * 2) uiomove() causes a page fault.
987 		 *
988 		 * We have to drop the contents lock to prevent the VM
989 		 * system from trying to reacquire it in ufs_getpage()
990 		 * should the uiomove cause a pagefault.
991 		 *
992 		 * We have to drop the reader vfs_dqrwlock here as well.
993 		 */
994 		rw_exit(&ip->i_contents);
995 		if (do_dqrwlock) {
996 			ASSERT(RW_LOCK_HELD(&ufsvfsp->vfs_dqrwlock));
997 			ASSERT(!(RW_WRITE_HELD(&ufsvfsp->vfs_dqrwlock)));
998 			rw_exit(&ufsvfsp->vfs_dqrwlock);
999 		}
1000 
1001 		newpage = 0;
1002 		premove_resid = uio->uio_resid;
1003 
1004 		/*
1005 		 * Touch the page and fault it in if it is not in core
1006 		 * before segmap_getmapflt or vpm_data_copy can lock it.
1007 		 * This is to avoid the deadlock if the buffer is mapped
1008 		 * to the same file through mmap which we want to write.
1009 		 */
1010 		uio_prefaultpages((long)n, uio);
1011 
1012 		if (vpm_enable) {
1013 			/*
1014 			 * Copy data. If new pages are created, part of
1015 			 * the page that is not written will be initizliazed
1016 			 * with zeros.
1017 			 */
1018 			error = vpm_data_copy(vp, (off + mapon), (uint_t)n,
1019 			    uio, !pagecreate, &newpage, 0, S_WRITE);
1020 		} else {
1021 
1022 			base = segmap_getmapflt(segkmap, vp, (off + mapon),
1023 			    (uint_t)n, !pagecreate, S_WRITE);
1024 
1025 			/*
1026 			 * segmap_pagecreate() returns 1 if it calls
1027 			 * page_create_va() to allocate any pages.
1028 			 */
1029 
1030 			if (pagecreate)
1031 				newpage = segmap_pagecreate(segkmap, base,
1032 				    (size_t)n, 0);
1033 
1034 			error = uiomove(base + mapon, (long)n, UIO_WRITE, uio);
1035 		}
1036 
1037 		/*
1038 		 * If "newpage" is set, then a new page was created and it
1039 		 * does not contain valid data, so it needs to be initialized
1040 		 * at this point.
1041 		 * Otherwise the page contains old data, which was overwritten
1042 		 * partially or as a whole in uiomove.
1043 		 * If there is only one iovec structure within uio, then
1044 		 * on error uiomove will not be able to update uio->uio_loffset
1045 		 * and we would zero the whole page here!
1046 		 *
1047 		 * If uiomove fails because of an error, the old valid data
1048 		 * is kept instead of filling the rest of the page with zero's.
1049 		 */
1050 		if (!vpm_enable && newpage &&
1051 		    uio->uio_loffset < roundup(off + mapon + n, PAGESIZE)) {
1052 			/*
1053 			 * We created pages w/o initializing them completely,
1054 			 * thus we need to zero the part that wasn't set up.
1055 			 * This happens on most EOF write cases and if
1056 			 * we had some sort of error during the uiomove.
1057 			 */
1058 			int nzero, nmoved;
1059 
1060 			nmoved = (int)(uio->uio_loffset - (off + mapon));
1061 			ASSERT(nmoved >= 0 && nmoved <= n);
1062 			nzero = roundup(on + n, PAGESIZE) - nmoved;
1063 			ASSERT(nzero > 0 && mapon + nmoved + nzero <= MAXBSIZE);
1064 			(void) kzero(base + mapon + nmoved, (uint_t)nzero);
1065 		}
1066 
1067 		/*
1068 		 * Unlock the pages allocated by page_create_va()
1069 		 * in segmap_pagecreate()
1070 		 */
1071 		if (!vpm_enable && newpage)
1072 			segmap_pageunlock(segkmap, base, (size_t)n, S_WRITE);
1073 
1074 		/*
1075 		 * If the size of the file changed, then update the
1076 		 * size field in the inode now.  This can't be done
1077 		 * before the call to segmap_pageunlock or there is
1078 		 * a potential deadlock with callers to ufs_putpage().
1079 		 * They will be holding i_contents and trying to lock
1080 		 * a page, while this thread is holding a page locked
1081 		 * and trying to acquire i_contents.
1082 		 */
1083 		if (i_size_changed) {
1084 			rw_enter(&ip->i_contents, RW_WRITER);
1085 			old_i_size = ip->i_size;
1086 			UFS_SET_ISIZE(uoff + n, ip);
1087 			TRANS_INODE(ufsvfsp, ip);
1088 			/*
1089 			 * file has grown larger than 2GB. Set flag
1090 			 * in superblock to indicate this, if it
1091 			 * is not already set.
1092 			 */
1093 			if ((ip->i_size > MAXOFF32_T) &&
1094 			    !(fs->fs_flags & FSLARGEFILES)) {
1095 				ASSERT(ufsvfsp->vfs_lfflags & UFS_LARGEFILES);
1096 				mutex_enter(&ufsvfsp->vfs_lock);
1097 				fs->fs_flags |= FSLARGEFILES;
1098 				ufs_sbwrite(ufsvfsp);
1099 				mutex_exit(&ufsvfsp->vfs_lock);
1100 			}
1101 			mutex_enter(&ip->i_tlock);
1102 			ip->i_writer = NULL;
1103 			cv_broadcast(&ip->i_wrcv);
1104 			mutex_exit(&ip->i_tlock);
1105 			rw_exit(&ip->i_contents);
1106 		}
1107 
1108 		if (error) {
1109 			/*
1110 			 * If we failed on a write, we may have already
1111 			 * allocated file blocks as well as pages.  It's
1112 			 * hard to undo the block allocation, but we must
1113 			 * be sure to invalidate any pages that may have
1114 			 * been allocated.
1115 			 *
1116 			 * If the page was created without initialization
1117 			 * then we must check if it should be possible
1118 			 * to destroy the new page and to keep the old data
1119 			 * on the disk.
1120 			 *
1121 			 * It is possible to destroy the page without
1122 			 * having to write back its contents only when
1123 			 * - the size of the file keeps unchanged
1124 			 * - bmap_write() did not allocate new disk blocks
1125 			 *   it is possible to create big files using "seek" and
1126 			 *   write to the end of the file. A "write" to a
1127 			 *   position before the end of the file would not
1128 			 *   change the size of the file but it would allocate
1129 			 *   new disk blocks.
1130 			 * - uiomove intended to overwrite the whole page.
1131 			 * - a new page was created (newpage == 1).
1132 			 */
1133 
1134 			if (i_size_changed == 0 && new_iblocks == 0 &&
1135 			    newpage) {
1136 
1137 				/* unwind what uiomove eventually last did */
1138 				uio->uio_resid = premove_resid;
1139 
1140 				/*
1141 				 * destroy the page, do not write ambiguous
1142 				 * data to the disk.
1143 				 */
1144 				flags = SM_DESTROY;
1145 			} else {
1146 				/*
1147 				 * write the page back to the disk, if dirty,
1148 				 * and remove the page from the cache.
1149 				 */
1150 				flags = SM_INVAL;
1151 			}
1152 
1153 			if (vpm_enable) {
1154 				/*
1155 				 *  Flush pages.
1156 				 */
1157 				(void) vpm_sync_pages(vp, off, n, flags);
1158 			} else {
1159 				(void) segmap_release(segkmap, base, flags);
1160 			}
1161 		} else {
1162 			flags = 0;
1163 			/*
1164 			 * Force write back for synchronous write cases.
1165 			 */
1166 			if ((ioflag & (FSYNC|FDSYNC)) || type == IFDIR) {
1167 				/*
1168 				 * If the sticky bit is set but the
1169 				 * execute bit is not set, we do a
1170 				 * synchronous write back and free
1171 				 * the page when done.  We set up swap
1172 				 * files to be handled this way to
1173 				 * prevent servers from keeping around
1174 				 * the client's swap pages too long.
1175 				 * XXX - there ought to be a better way.
1176 				 */
1177 				if (IS_SWAPVP(vp)) {
1178 					flags = SM_WRITE | SM_FREE |
1179 					    SM_DONTNEED;
1180 					iupdat_flag = 0;
1181 				} else {
1182 					flags = SM_WRITE;
1183 				}
1184 			} else if (n + on == MAXBSIZE || IS_SWAPVP(vp)) {
1185 				/*
1186 				 * Have written a whole block.
1187 				 * Start an asynchronous write and
1188 				 * mark the buffer to indicate that
1189 				 * it won't be needed again soon.
1190 				 */
1191 				flags = SM_WRITE | SM_ASYNC | SM_DONTNEED;
1192 			}
1193 			if (vpm_enable) {
1194 				/*
1195 				 * Flush pages.
1196 				 */
1197 				error = vpm_sync_pages(vp, off, n, flags);
1198 			} else {
1199 				error = segmap_release(segkmap, base, flags);
1200 			}
1201 			/*
1202 			 * If the operation failed and is synchronous,
1203 			 * then we need to unwind what uiomove() last
1204 			 * did so we can potentially return an error to
1205 			 * the caller.  If this write operation was
1206 			 * done in two pieces and the first succeeded,
1207 			 * then we won't return an error for the second
1208 			 * piece that failed.  However, we only want to
1209 			 * return a resid value that reflects what was
1210 			 * really done.
1211 			 *
1212 			 * Failures for non-synchronous operations can
1213 			 * be ignored since the page subsystem will
1214 			 * retry the operation until it succeeds or the
1215 			 * file system is unmounted.
1216 			 */
1217 			if (error) {
1218 				if ((ioflag & (FSYNC | FDSYNC)) ||
1219 				    type == IFDIR) {
1220 					uio->uio_resid = premove_resid;
1221 				} else {
1222 					error = 0;
1223 				}
1224 			}
1225 		}
1226 
1227 		/*
1228 		 * Re-acquire contents lock.
1229 		 * If it was dropped, reacquire reader vfs_dqrwlock as well.
1230 		 */
1231 		if (do_dqrwlock)
1232 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
1233 		rw_enter(&ip->i_contents, RW_WRITER);
1234 
1235 		/*
1236 		 * If the uiomove() failed or if a synchronous
1237 		 * page push failed, fix up i_size.
1238 		 */
1239 		if (error) {
1240 			if (i_size_changed) {
1241 				/*
1242 				 * The uiomove failed, and we
1243 				 * allocated blocks,so get rid
1244 				 * of them.
1245 				 */
1246 				(void) ufs_itrunc(ip, old_i_size, 0, cr);
1247 			}
1248 		} else {
1249 			/*
1250 			 * XXX - Can this be out of the loop?
1251 			 */
1252 			ip->i_flag |= IUPD | ICHG;
1253 			/*
1254 			 * Only do one increase of i_seq for multiple
1255 			 * pieces.  Because we drop locks, record
1256 			 * the fact that we changed the timestamp and
1257 			 * are deferring the increase in case another thread
1258 			 * pushes our timestamp update.
1259 			 */
1260 			i_seq_needed = 1;
1261 			ip->i_flag |= ISEQ;
1262 			if (i_size_changed)
1263 				ip->i_flag |= IATTCHG;
1264 			if ((ip->i_mode & (IEXEC | (IEXEC >> 3) |
1265 			    (IEXEC >> 6))) != 0 &&
1266 			    (ip->i_mode & (ISUID | ISGID)) != 0 &&
1267 			    secpolicy_vnode_setid_retain(cr,
1268 			    (ip->i_mode & ISUID) != 0 && ip->i_uid == 0) != 0) {
1269 				/*
1270 				 * Clear Set-UID & Set-GID bits on
1271 				 * successful write if not privileged
1272 				 * and at least one of the execute bits
1273 				 * is set.  If we always clear Set-GID,
1274 				 * mandatory file and record locking is
1275 				 * unuseable.
1276 				 */
1277 				ip->i_mode &= ~(ISUID | ISGID);
1278 			}
1279 		}
1280 		/*
1281 		 * In the case the FDSYNC flag is set and this is a
1282 		 * "rewrite" we won't log a delta.
1283 		 * The FSYNC flag overrides all cases.
1284 		 */
1285 		if (!ufs_check_rewrite(ip, uio, ioflag) || !(ioflag & FDSYNC)) {
1286 			TRANS_INODE(ufsvfsp, ip);
1287 		}
1288 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
1289 
1290 out:
1291 	/*
1292 	 * Make sure i_seq is increased at least once per write
1293 	 */
1294 	if (i_seq_needed) {
1295 		ip->i_seq++;
1296 		ip->i_flag &= ~ISEQ;	/* no longer deferred */
1297 	}
1298 
1299 	/*
1300 	 * Inode is updated according to this table -
1301 	 *
1302 	 *   FSYNC	  FDSYNC(posix.4)
1303 	 *   --------------------------
1304 	 *   always@	  IATTCHG|IBDWRITE
1305 	 *
1306 	 * @ - 	If we are doing synchronous write the only time we should
1307 	 *	not be sync'ing the ip here is if we have the stickyhack
1308 	 *	activated, the file is marked with the sticky bit and
1309 	 *	no exec bit, the file length has not been changed and
1310 	 *	no new blocks have been allocated during this write.
1311 	 */
1312 
1313 	if ((ip->i_flag & ISYNC) != 0) {
1314 		/*
1315 		 * we have eliminated nosync
1316 		 */
1317 		if ((ip->i_flag & (IATTCHG|IBDWRITE)) ||
1318 		    ((ioflag & FSYNC) && iupdat_flag)) {
1319 			ufs_iupdat(ip, 1);
1320 		}
1321 	}
1322 
1323 	/*
1324 	 * If we've already done a partial-write, terminate
1325 	 * the write but return no error unless the error is ENOSPC
1326 	 * because the caller can detect this and free resources and
1327 	 * try again.
1328 	 */
1329 	if ((start_resid != uio->uio_resid) && (error != ENOSPC))
1330 		error = 0;
1331 
1332 	ip->i_flag &= ~(INOACC | ISYNC);
1333 	ITIMES_NOLOCK(ip);
1334 	return (error);
1335 }
1336 
1337 /*
1338  * rdip does the real work of read requests for ufs.
1339  */
1340 int
rdip(struct inode * ip,struct uio * uio,int ioflag,cred_t * cr)1341 rdip(struct inode *ip, struct uio *uio, int ioflag, cred_t *cr)
1342 {
1343 	u_offset_t off;
1344 	caddr_t base;
1345 	struct fs *fs;
1346 	struct ufsvfs *ufsvfsp;
1347 	struct vnode *vp;
1348 	long oresid = uio->uio_resid;
1349 	u_offset_t n, on, mapon;
1350 	int error = 0;
1351 	int doupdate = 1;
1352 	uint_t flags;
1353 	int dofree, directio_status;
1354 	krw_t rwtype;
1355 	o_mode_t type;
1356 	clock_t	now;
1357 
1358 	vp = ITOV(ip);
1359 
1360 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
1361 
1362 	ufsvfsp = ip->i_ufsvfs;
1363 
1364 	if (ufsvfsp == NULL)
1365 		return (EIO);
1366 
1367 	fs = ufsvfsp->vfs_fs;
1368 
1369 	/* check for valid filetype */
1370 	type = ip->i_mode & IFMT;
1371 	if ((type != IFREG) && (type != IFDIR) && (type != IFATTRDIR) &&
1372 	    (type != IFLNK) && (type != IFSHAD)) {
1373 		return (EIO);
1374 	}
1375 
1376 	if (uio->uio_loffset > UFS_MAXOFFSET_T) {
1377 		error = 0;
1378 		goto out;
1379 	}
1380 	if (uio->uio_loffset < (offset_t)0) {
1381 		return (EINVAL);
1382 	}
1383 	if (uio->uio_resid == 0) {
1384 		return (0);
1385 	}
1386 
1387 	if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) && (fs->fs_ronly == 0) &&
1388 	    (!ufsvfsp->vfs_noatime)) {
1389 		mutex_enter(&ip->i_tlock);
1390 		ip->i_flag |= IACC;
1391 		mutex_exit(&ip->i_tlock);
1392 	}
1393 	/*
1394 	 * Try to go direct
1395 	 */
1396 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio) {
1397 		error = ufs_directio_read(ip, uio, cr, &directio_status);
1398 		if (directio_status == DIRECTIO_SUCCESS)
1399 			goto out;
1400 	}
1401 
1402 	rwtype = (rw_write_held(&ip->i_contents)?RW_WRITER:RW_READER);
1403 
1404 	do {
1405 		offset_t diff;
1406 		u_offset_t uoff = uio->uio_loffset;
1407 		off = uoff & (offset_t)MAXBMASK;
1408 		mapon = (u_offset_t)(uoff & (offset_t)MAXBOFFSET);
1409 		on = (u_offset_t)blkoff(fs, uoff);
1410 		n = MIN((u_offset_t)fs->fs_bsize - on,
1411 		    (u_offset_t)uio->uio_resid);
1412 
1413 		diff = ip->i_size - uoff;
1414 
1415 		if (diff <= (offset_t)0) {
1416 			error = 0;
1417 			goto out;
1418 		}
1419 		if (diff < (offset_t)n)
1420 			n = (int)diff;
1421 
1422 		/*
1423 		 * We update smallfile2 and smallfile1 at most every second.
1424 		 */
1425 		now = ddi_get_lbolt();
1426 		if (now >= smallfile_update) {
1427 			uint64_t percpufreeb;
1428 			if (smallfile1_d == 0) smallfile1_d = SMALLFILE1_D;
1429 			if (smallfile2_d == 0) smallfile2_d = SMALLFILE2_D;
1430 			percpufreeb = ptob((uint64_t)freemem) / ncpus_online;
1431 			smallfile1 = percpufreeb / smallfile1_d;
1432 			smallfile2 = percpufreeb / smallfile2_d;
1433 			smallfile1 = MAX(smallfile1, smallfile);
1434 			smallfile1 = MAX(smallfile1, smallfile64);
1435 			smallfile2 = MAX(smallfile1, smallfile2);
1436 			smallfile_update = now + hz;
1437 		}
1438 
1439 		dofree = freebehind &&
1440 		    ip->i_nextr == (off & PAGEMASK) && off > smallfile1;
1441 
1442 		/*
1443 		 * At this point we can enter ufs_getpage() in one of two
1444 		 * ways:
1445 		 * 1) segmap_getmapflt() calls ufs_getpage() when the
1446 		 *    forcefault parameter is true (value of 1 is passed)
1447 		 * 2) uiomove() causes a page fault.
1448 		 *
1449 		 * We cannot hold onto an i_contents reader lock without
1450 		 * risking deadlock in ufs_getpage() so drop a reader lock.
1451 		 * The ufs_getpage() dolock logic already allows for a
1452 		 * thread holding i_contents as writer to work properly
1453 		 * so we keep a writer lock.
1454 		 */
1455 		if (rwtype == RW_READER)
1456 			rw_exit(&ip->i_contents);
1457 
1458 		if (vpm_enable) {
1459 			/*
1460 			 * Copy data.
1461 			 */
1462 			error = vpm_data_copy(vp, (off + mapon), (uint_t)n,
1463 			    uio, 1, NULL, 0, S_READ);
1464 		} else {
1465 			base = segmap_getmapflt(segkmap, vp, (off + mapon),
1466 			    (uint_t)n, 1, S_READ);
1467 			error = uiomove(base + mapon, (long)n, UIO_READ, uio);
1468 		}
1469 
1470 		flags = 0;
1471 		if (!error) {
1472 			/*
1473 			 * If  reading sequential  we won't need  this
1474 			 * buffer again  soon.  For  offsets in  range
1475 			 * [smallfile1,  smallfile2] release the pages
1476 			 * at   the  tail  of the   cache list, larger
1477 			 * offsets are released at the head.
1478 			 */
1479 			if (dofree) {
1480 				flags = SM_FREE | SM_ASYNC;
1481 				if ((cache_read_ahead == 0) &&
1482 				    (off > smallfile2))
1483 					flags |=  SM_DONTNEED;
1484 			}
1485 			/*
1486 			 * In POSIX SYNC (FSYNC and FDSYNC) read mode,
1487 			 * we want to make sure that the page which has
1488 			 * been read, is written on disk if it is dirty.
1489 			 * And corresponding indirect blocks should also
1490 			 * be flushed out.
1491 			 */
1492 			if ((ioflag & FRSYNC) && (ioflag & (FSYNC|FDSYNC))) {
1493 				flags &= ~SM_ASYNC;
1494 				flags |= SM_WRITE;
1495 			}
1496 			if (vpm_enable) {
1497 				error = vpm_sync_pages(vp, off, n, flags);
1498 			} else {
1499 				error = segmap_release(segkmap, base, flags);
1500 			}
1501 		} else {
1502 			if (vpm_enable) {
1503 				(void) vpm_sync_pages(vp, off, n, flags);
1504 			} else {
1505 				(void) segmap_release(segkmap, base, flags);
1506 			}
1507 		}
1508 
1509 		if (rwtype == RW_READER)
1510 			rw_enter(&ip->i_contents, rwtype);
1511 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
1512 out:
1513 	/*
1514 	 * Inode is updated according to this table if FRSYNC is set.
1515 	 *
1516 	 *   FSYNC	  FDSYNC(posix.4)
1517 	 *   --------------------------
1518 	 *   always	  IATTCHG|IBDWRITE
1519 	 */
1520 	/*
1521 	 * The inode is not updated if we're logging and the inode is a
1522 	 * directory with FRSYNC, FSYNC and FDSYNC flags set.
1523 	 */
1524 	if (ioflag & FRSYNC) {
1525 		if (TRANS_ISTRANS(ufsvfsp) && ((ip->i_mode & IFMT) == IFDIR)) {
1526 			doupdate = 0;
1527 		}
1528 		if (doupdate) {
1529 			if ((ioflag & FSYNC) ||
1530 			    ((ioflag & FDSYNC) &&
1531 			    (ip->i_flag & (IATTCHG|IBDWRITE)))) {
1532 				ufs_iupdat(ip, 1);
1533 			}
1534 		}
1535 	}
1536 	/*
1537 	 * If we've already done a partial read, terminate
1538 	 * the read but return no error.
1539 	 */
1540 	if (oresid != uio->uio_resid)
1541 		error = 0;
1542 	ITIMES(ip);
1543 
1544 	return (error);
1545 }
1546 
1547 /* ARGSUSED */
1548 static int
ufs_ioctl(struct vnode * vp,int cmd,intptr_t arg,int flag,struct cred * cr,int * rvalp,caller_context_t * ct)1549 ufs_ioctl(
1550 	struct vnode	*vp,
1551 	int		cmd,
1552 	intptr_t	arg,
1553 	int		flag,
1554 	struct cred	*cr,
1555 	int		*rvalp,
1556 	caller_context_t *ct)
1557 {
1558 	struct lockfs	lockfs, lockfs_out;
1559 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
1560 	char		*comment, *original_comment;
1561 	struct fs	*fs;
1562 	struct ulockfs	*ulp;
1563 	offset_t	off;
1564 	extern int	maxphys;
1565 	int		error;
1566 	int		issync;
1567 	int		trans_size;
1568 
1569 
1570 	/*
1571 	 * forcibly unmounted
1572 	 */
1573 	if (ufsvfsp == NULL || vp->v_vfsp == NULL ||
1574 	    vp->v_vfsp->vfs_flag & VFS_UNMOUNTED)
1575 		return (EIO);
1576 	fs = ufsvfsp->vfs_fs;
1577 
1578 	if (cmd == Q_QUOTACTL) {
1579 		error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_QUOTA_MASK);
1580 		if (error)
1581 			return (error);
1582 
1583 		if (ulp) {
1584 			TRANS_BEGIN_ASYNC(ufsvfsp, TOP_QUOTA,
1585 			    TOP_SETQUOTA_SIZE(fs));
1586 		}
1587 
1588 		error = quotactl(vp, arg, flag, cr);
1589 
1590 		if (ulp) {
1591 			TRANS_END_ASYNC(ufsvfsp, TOP_QUOTA,
1592 			    TOP_SETQUOTA_SIZE(fs));
1593 			ufs_lockfs_end(ulp);
1594 		}
1595 		return (error);
1596 	}
1597 
1598 	switch (cmd) {
1599 		case _FIOLFS:
1600 			/*
1601 			 * file system locking
1602 			 */
1603 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1604 				return (EPERM);
1605 
1606 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1607 				if (copyin((caddr_t)arg, &lockfs,
1608 				    sizeof (struct lockfs)))
1609 					return (EFAULT);
1610 			}
1611 #ifdef _SYSCALL32_IMPL
1612 			else {
1613 				struct lockfs32	lockfs32;
1614 				/* Translate ILP32 lockfs to LP64 lockfs */
1615 				if (copyin((caddr_t)arg, &lockfs32,
1616 				    sizeof (struct lockfs32)))
1617 					return (EFAULT);
1618 				lockfs.lf_lock = (ulong_t)lockfs32.lf_lock;
1619 				lockfs.lf_flags = (ulong_t)lockfs32.lf_flags;
1620 				lockfs.lf_key = (ulong_t)lockfs32.lf_key;
1621 				lockfs.lf_comlen = (ulong_t)lockfs32.lf_comlen;
1622 				lockfs.lf_comment =
1623 				    (caddr_t)(uintptr_t)lockfs32.lf_comment;
1624 			}
1625 #endif /* _SYSCALL32_IMPL */
1626 
1627 			if (lockfs.lf_comlen) {
1628 				if (lockfs.lf_comlen > LOCKFS_MAXCOMMENTLEN)
1629 					return (ENAMETOOLONG);
1630 				comment =
1631 				    kmem_alloc(lockfs.lf_comlen, KM_SLEEP);
1632 				if (copyin(lockfs.lf_comment, comment,
1633 				    lockfs.lf_comlen)) {
1634 					kmem_free(comment, lockfs.lf_comlen);
1635 					return (EFAULT);
1636 				}
1637 				original_comment = lockfs.lf_comment;
1638 				lockfs.lf_comment = comment;
1639 			}
1640 			if ((error = ufs_fiolfs(vp, &lockfs, 0)) == 0) {
1641 				lockfs.lf_comment = original_comment;
1642 
1643 				if ((flag & DATAMODEL_MASK) ==
1644 				    DATAMODEL_NATIVE) {
1645 					(void) copyout(&lockfs, (caddr_t)arg,
1646 					    sizeof (struct lockfs));
1647 				}
1648 #ifdef _SYSCALL32_IMPL
1649 				else {
1650 					struct lockfs32	lockfs32;
1651 					/* Translate LP64 to ILP32 lockfs */
1652 					lockfs32.lf_lock =
1653 					    (uint32_t)lockfs.lf_lock;
1654 					lockfs32.lf_flags =
1655 					    (uint32_t)lockfs.lf_flags;
1656 					lockfs32.lf_key =
1657 					    (uint32_t)lockfs.lf_key;
1658 					lockfs32.lf_comlen =
1659 					    (uint32_t)lockfs.lf_comlen;
1660 					lockfs32.lf_comment =
1661 					    (uint32_t)(uintptr_t)
1662 					    lockfs.lf_comment;
1663 					(void) copyout(&lockfs32, (caddr_t)arg,
1664 					    sizeof (struct lockfs32));
1665 				}
1666 #endif /* _SYSCALL32_IMPL */
1667 
1668 			} else {
1669 				if (lockfs.lf_comlen)
1670 					kmem_free(comment, lockfs.lf_comlen);
1671 			}
1672 			return (error);
1673 
1674 		case _FIOLFSS:
1675 			/*
1676 			 * get file system locking status
1677 			 */
1678 
1679 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1680 				if (copyin((caddr_t)arg, &lockfs,
1681 				    sizeof (struct lockfs)))
1682 					return (EFAULT);
1683 			}
1684 #ifdef _SYSCALL32_IMPL
1685 			else {
1686 				struct lockfs32	lockfs32;
1687 				/* Translate ILP32 lockfs to LP64 lockfs */
1688 				if (copyin((caddr_t)arg, &lockfs32,
1689 				    sizeof (struct lockfs32)))
1690 					return (EFAULT);
1691 				lockfs.lf_lock = (ulong_t)lockfs32.lf_lock;
1692 				lockfs.lf_flags = (ulong_t)lockfs32.lf_flags;
1693 				lockfs.lf_key = (ulong_t)lockfs32.lf_key;
1694 				lockfs.lf_comlen = (ulong_t)lockfs32.lf_comlen;
1695 				lockfs.lf_comment =
1696 				    (caddr_t)(uintptr_t)lockfs32.lf_comment;
1697 			}
1698 #endif /* _SYSCALL32_IMPL */
1699 
1700 			if (error =  ufs_fiolfss(vp, &lockfs_out))
1701 				return (error);
1702 			lockfs.lf_lock = lockfs_out.lf_lock;
1703 			lockfs.lf_key = lockfs_out.lf_key;
1704 			lockfs.lf_flags = lockfs_out.lf_flags;
1705 			lockfs.lf_comlen = MIN(lockfs.lf_comlen,
1706 			    lockfs_out.lf_comlen);
1707 
1708 			if ((flag & DATAMODEL_MASK) == DATAMODEL_NATIVE) {
1709 				if (copyout(&lockfs, (caddr_t)arg,
1710 				    sizeof (struct lockfs)))
1711 					return (EFAULT);
1712 			}
1713 #ifdef _SYSCALL32_IMPL
1714 			else {
1715 				/* Translate LP64 to ILP32 lockfs */
1716 				struct lockfs32	lockfs32;
1717 				lockfs32.lf_lock = (uint32_t)lockfs.lf_lock;
1718 				lockfs32.lf_flags = (uint32_t)lockfs.lf_flags;
1719 				lockfs32.lf_key = (uint32_t)lockfs.lf_key;
1720 				lockfs32.lf_comlen = (uint32_t)lockfs.lf_comlen;
1721 				lockfs32.lf_comment =
1722 				    (uint32_t)(uintptr_t)lockfs.lf_comment;
1723 				if (copyout(&lockfs32, (caddr_t)arg,
1724 				    sizeof (struct lockfs32)))
1725 					return (EFAULT);
1726 			}
1727 #endif /* _SYSCALL32_IMPL */
1728 
1729 			if (lockfs.lf_comlen &&
1730 			    lockfs.lf_comment && lockfs_out.lf_comment)
1731 				if (copyout(lockfs_out.lf_comment,
1732 				    lockfs.lf_comment, lockfs.lf_comlen))
1733 					return (EFAULT);
1734 			return (0);
1735 
1736 		case _FIOSATIME:
1737 			/*
1738 			 * set access time
1739 			 */
1740 
1741 			/*
1742 			 * if mounted w/o atime, return quietly.
1743 			 * I briefly thought about returning ENOSYS, but
1744 			 * figured that most apps would consider this fatal
1745 			 * but the idea is to make this as seamless as poss.
1746 			 */
1747 			if (ufsvfsp->vfs_noatime)
1748 				return (0);
1749 
1750 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1751 			    ULOCKFS_SETATTR_MASK);
1752 			if (error)
1753 				return (error);
1754 
1755 			if (ulp) {
1756 				trans_size = (int)TOP_SETATTR_SIZE(VTOI(vp));
1757 				TRANS_BEGIN_CSYNC(ufsvfsp, issync,
1758 				    TOP_SETATTR, trans_size);
1759 			}
1760 
1761 			error = ufs_fiosatime(vp, (struct timeval *)arg,
1762 			    flag, cr);
1763 
1764 			if (ulp) {
1765 				TRANS_END_CSYNC(ufsvfsp, error, issync,
1766 				    TOP_SETATTR, trans_size);
1767 				ufs_lockfs_end(ulp);
1768 			}
1769 			return (error);
1770 
1771 		case _FIOSDIO:
1772 			/*
1773 			 * set delayed-io
1774 			 */
1775 			return (ufs_fiosdio(vp, (uint_t *)arg, flag, cr));
1776 
1777 		case _FIOGDIO:
1778 			/*
1779 			 * get delayed-io
1780 			 */
1781 			return (ufs_fiogdio(vp, (uint_t *)arg, flag, cr));
1782 
1783 		case _FIOIO:
1784 			/*
1785 			 * inode open
1786 			 */
1787 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1788 			    ULOCKFS_VGET_MASK);
1789 			if (error)
1790 				return (error);
1791 
1792 			error = ufs_fioio(vp, (struct fioio *)arg, flag, cr);
1793 
1794 			if (ulp) {
1795 				ufs_lockfs_end(ulp);
1796 			}
1797 			return (error);
1798 
1799 		case _FIOFFS:
1800 			/*
1801 			 * file system flush (push w/invalidate)
1802 			 */
1803 			if ((caddr_t)arg != NULL)
1804 				return (EINVAL);
1805 			return (ufs_fioffs(vp, NULL, cr));
1806 
1807 		case _FIOISBUSY:
1808 			/*
1809 			 * Contract-private interface for Legato
1810 			 * Purge this vnode from the DNLC and decide
1811 			 * if this vnode is busy (*arg == 1) or not
1812 			 * (*arg == 0)
1813 			 */
1814 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1815 				return (EPERM);
1816 			error = ufs_fioisbusy(vp, (int *)arg, cr);
1817 			return (error);
1818 
1819 		case _FIODIRECTIO:
1820 			return (ufs_fiodirectio(vp, (int)arg, cr));
1821 
1822 		case _FIOTUNE:
1823 			/*
1824 			 * Tune the file system (aka setting fs attributes)
1825 			 */
1826 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1827 			    ULOCKFS_SETATTR_MASK);
1828 			if (error)
1829 				return (error);
1830 
1831 			error = ufs_fiotune(vp, (struct fiotune *)arg, cr);
1832 
1833 			if (ulp)
1834 				ufs_lockfs_end(ulp);
1835 			return (error);
1836 
1837 		case _FIOLOGENABLE:
1838 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1839 				return (EPERM);
1840 			return (ufs_fiologenable(vp, (void *)arg, cr, flag));
1841 
1842 		case _FIOLOGDISABLE:
1843 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1844 				return (EPERM);
1845 			return (ufs_fiologdisable(vp, (void *)arg, cr, flag));
1846 
1847 		case _FIOISLOG:
1848 			return (ufs_fioislog(vp, (void *)arg, cr, flag));
1849 
1850 		case _FIOSNAPSHOTCREATE_MULTI:
1851 		{
1852 			struct fiosnapcreate_multi	fc, *fcp;
1853 			size_t	fcm_size;
1854 
1855 			if (copyin((void *)arg, &fc, sizeof (fc)))
1856 				return (EFAULT);
1857 			if (fc.backfilecount > MAX_BACKFILE_COUNT)
1858 				return (EINVAL);
1859 			fcm_size = sizeof (struct fiosnapcreate_multi) +
1860 			    (fc.backfilecount - 1) * sizeof (int);
1861 			fcp = (struct fiosnapcreate_multi *)
1862 			    kmem_alloc(fcm_size, KM_SLEEP);
1863 			if (copyin((void *)arg, fcp, fcm_size)) {
1864 				kmem_free(fcp, fcm_size);
1865 				return (EFAULT);
1866 			}
1867 			error = ufs_snap_create(vp, fcp, cr);
1868 			/*
1869 			 * Do copyout even if there is an error because
1870 			 * the details of error is stored in fcp.
1871 			 */
1872 			if (copyout(fcp, (void *)arg, fcm_size))
1873 				error = EFAULT;
1874 			kmem_free(fcp, fcm_size);
1875 			return (error);
1876 		}
1877 
1878 		case _FIOSNAPSHOTDELETE:
1879 		{
1880 			struct fiosnapdelete	fc;
1881 
1882 			if (copyin((void *)arg, &fc, sizeof (fc)))
1883 				return (EFAULT);
1884 			error = ufs_snap_delete(vp, &fc, cr);
1885 			if (!error && copyout(&fc, (void *)arg, sizeof (fc)))
1886 				error = EFAULT;
1887 			return (error);
1888 		}
1889 
1890 		case _FIOGETSUPERBLOCK:
1891 			if (copyout(fs, (void *)arg, SBSIZE))
1892 				return (EFAULT);
1893 			return (0);
1894 
1895 		case _FIOGETMAXPHYS:
1896 			if (copyout(&maxphys, (void *)arg, sizeof (maxphys)))
1897 				return (EFAULT);
1898 			return (0);
1899 
1900 		/*
1901 		 * The following 3 ioctls are for TSufs support
1902 		 * although could potentially be used elsewhere
1903 		 */
1904 		case _FIO_SET_LUFS_DEBUG:
1905 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1906 				return (EPERM);
1907 			lufs_debug = (uint32_t)arg;
1908 			return (0);
1909 
1910 		case _FIO_SET_LUFS_ERROR:
1911 			if (secpolicy_fs_config(cr, ufsvfsp->vfs_vfs) != 0)
1912 				return (EPERM);
1913 			TRANS_SETERROR(ufsvfsp);
1914 			return (0);
1915 
1916 		case _FIO_GET_TOP_STATS:
1917 		{
1918 			fio_lufs_stats_t *ls;
1919 			ml_unit_t *ul = ufsvfsp->vfs_log;
1920 
1921 			ls = kmem_zalloc(sizeof (*ls), KM_SLEEP);
1922 			ls->ls_debug = ul->un_debug; /* return debug value */
1923 			/* Copy stucture if statistics are being kept */
1924 			if (ul->un_logmap->mtm_tops) {
1925 				ls->ls_topstats = *(ul->un_logmap->mtm_tops);
1926 			}
1927 			error = 0;
1928 			if (copyout(ls, (void *)arg, sizeof (*ls)))
1929 				error = EFAULT;
1930 			kmem_free(ls, sizeof (*ls));
1931 			return (error);
1932 		}
1933 
1934 		case _FIO_SEEK_DATA:
1935 		case _FIO_SEEK_HOLE:
1936 			if (ddi_copyin((void *)arg, &off, sizeof (off), flag))
1937 				return (EFAULT);
1938 			/* offset paramater is in/out */
1939 			error = ufs_fio_holey(vp, cmd, &off);
1940 			if (error)
1941 				return (error);
1942 			if (ddi_copyout(&off, (void *)arg, sizeof (off), flag))
1943 				return (EFAULT);
1944 			return (0);
1945 
1946 		case _FIO_COMPRESSED:
1947 		{
1948 			/*
1949 			 * This is a project private ufs ioctl() to mark
1950 			 * the inode as that belonging to a compressed
1951 			 * file. This is used to mark individual
1952 			 * compressed files in a miniroot archive.
1953 			 * The files compressed in this manner are
1954 			 * automatically decompressed by the dcfs filesystem
1955 			 * (via an interception in ufs_lookup - see decompvp())
1956 			 * which is layered on top of ufs on a system running
1957 			 * from the archive. See uts/common/fs/dcfs for details.
1958 			 * This ioctl only marks the file as compressed - the
1959 			 * actual compression is done by fiocompress (a
1960 			 * userland utility) which invokes this ioctl().
1961 			 */
1962 			struct inode *ip = VTOI(vp);
1963 
1964 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
1965 			    ULOCKFS_SETATTR_MASK);
1966 			if (error)
1967 				return (error);
1968 
1969 			if (ulp) {
1970 				TRANS_BEGIN_ASYNC(ufsvfsp, TOP_IUPDAT,
1971 				    TOP_IUPDAT_SIZE(ip));
1972 			}
1973 
1974 			error = ufs_mark_compressed(vp);
1975 
1976 			if (ulp) {
1977 				TRANS_END_ASYNC(ufsvfsp, TOP_IUPDAT,
1978 				    TOP_IUPDAT_SIZE(ip));
1979 				ufs_lockfs_end(ulp);
1980 			}
1981 
1982 			return (error);
1983 
1984 		}
1985 
1986 		default:
1987 			return (ENOTTY);
1988 	}
1989 }
1990 
1991 
1992 /* ARGSUSED */
1993 static int
ufs_getattr(struct vnode * vp,struct vattr * vap,int flags,struct cred * cr,caller_context_t * ct)1994 ufs_getattr(struct vnode *vp, struct vattr *vap, int flags,
1995 	struct cred *cr, caller_context_t *ct)
1996 {
1997 	struct inode *ip = VTOI(vp);
1998 	struct ufsvfs *ufsvfsp;
1999 	int err;
2000 
2001 	if (vap->va_mask == AT_SIZE) {
2002 		/*
2003 		 * for performance, if only the size is requested don't bother
2004 		 * with anything else.
2005 		 */
2006 		UFS_GET_ISIZE(&vap->va_size, ip);
2007 		return (0);
2008 	}
2009 
2010 	/*
2011 	 * inlined lockfs checks
2012 	 */
2013 	ufsvfsp = ip->i_ufsvfs;
2014 	if ((ufsvfsp == NULL) || ULOCKFS_IS_HLOCK(&ufsvfsp->vfs_ulockfs)) {
2015 		err = EIO;
2016 		goto out;
2017 	}
2018 
2019 	rw_enter(&ip->i_contents, RW_READER);
2020 	/*
2021 	 * Return all the attributes.  This should be refined so
2022 	 * that it only returns what's asked for.
2023 	 */
2024 
2025 	/*
2026 	 * Copy from inode table.
2027 	 */
2028 	vap->va_type = vp->v_type;
2029 	vap->va_mode = ip->i_mode & MODEMASK;
2030 	/*
2031 	 * If there is an ACL and there is a mask entry, then do the
2032 	 * extra work that completes the equivalent of an acltomode(3)
2033 	 * call.  According to POSIX P1003.1e, the acl mask should be
2034 	 * returned in the group permissions field.
2035 	 *
2036 	 * - start with the original permission and mode bits (from above)
2037 	 * - clear the group owner bits
2038 	 * - add in the mask bits.
2039 	 */
2040 	if (ip->i_ufs_acl && ip->i_ufs_acl->aclass.acl_ismask) {
2041 		vap->va_mode &= ~((VREAD | VWRITE | VEXEC) >> 3);
2042 		vap->va_mode |=
2043 		    (ip->i_ufs_acl->aclass.acl_maskbits & PERMMASK) << 3;
2044 	}
2045 	vap->va_uid = ip->i_uid;
2046 	vap->va_gid = ip->i_gid;
2047 	vap->va_fsid = ip->i_dev;
2048 	vap->va_nodeid = (ino64_t)ip->i_number;
2049 	vap->va_nlink = ip->i_nlink;
2050 	vap->va_size = ip->i_size;
2051 	if (vp->v_type == VCHR || vp->v_type == VBLK)
2052 		vap->va_rdev = ip->i_rdev;
2053 	else
2054 		vap->va_rdev = 0;	/* not a b/c spec. */
2055 	mutex_enter(&ip->i_tlock);
2056 	ITIMES_NOLOCK(ip);	/* mark correct time in inode */
2057 	vap->va_seq = ip->i_seq;
2058 	vap->va_atime.tv_sec = (time_t)ip->i_atime.tv_sec;
2059 	vap->va_atime.tv_nsec = ip->i_atime.tv_usec*1000;
2060 	vap->va_mtime.tv_sec = (time_t)ip->i_mtime.tv_sec;
2061 	vap->va_mtime.tv_nsec = ip->i_mtime.tv_usec*1000;
2062 	vap->va_ctime.tv_sec = (time_t)ip->i_ctime.tv_sec;
2063 	vap->va_ctime.tv_nsec = ip->i_ctime.tv_usec*1000;
2064 	mutex_exit(&ip->i_tlock);
2065 
2066 	switch (ip->i_mode & IFMT) {
2067 
2068 	case IFBLK:
2069 		vap->va_blksize = MAXBSIZE;		/* was BLKDEV_IOSIZE */
2070 		break;
2071 
2072 	case IFCHR:
2073 		vap->va_blksize = MAXBSIZE;
2074 		break;
2075 
2076 	default:
2077 		vap->va_blksize = ip->i_fs->fs_bsize;
2078 		break;
2079 	}
2080 	vap->va_nblocks = (fsblkcnt64_t)ip->i_blocks;
2081 	rw_exit(&ip->i_contents);
2082 	err = 0;
2083 
2084 out:
2085 	return (err);
2086 }
2087 
2088 /*
2089  * Special wrapper to provide a callback for secpolicy_vnode_setattr().
2090  * The i_contents lock is already held by the caller and we need to
2091  * declare the inode as 'void *' argument.
2092  */
2093 static int
ufs_priv_access(void * vip,int mode,struct cred * cr)2094 ufs_priv_access(void *vip, int mode, struct cred *cr)
2095 {
2096 	struct inode *ip = vip;
2097 
2098 	return (ufs_iaccess(ip, mode, cr, 0));
2099 }
2100 
2101 /*ARGSUSED4*/
2102 static int
ufs_setattr(struct vnode * vp,struct vattr * vap,int flags,struct cred * cr,caller_context_t * ct)2103 ufs_setattr(
2104 	struct vnode *vp,
2105 	struct vattr *vap,
2106 	int flags,
2107 	struct cred *cr,
2108 	caller_context_t *ct)
2109 {
2110 	struct inode *ip = VTOI(vp);
2111 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
2112 	struct fs *fs;
2113 	struct ulockfs *ulp;
2114 	char *errmsg1;
2115 	char *errmsg2;
2116 	long blocks;
2117 	long int mask = vap->va_mask;
2118 	size_t len1, len2;
2119 	int issync;
2120 	int trans_size;
2121 	int dotrans;
2122 	int dorwlock;
2123 	int error;
2124 	int owner_change;
2125 	int dodqlock;
2126 	timestruc_t now;
2127 	vattr_t oldva;
2128 	int retry = 1;
2129 	int indeadlock;
2130 
2131 	/*
2132 	 * Cannot set these attributes.
2133 	 */
2134 	if ((mask & AT_NOSET) || (mask & AT_XVATTR))
2135 		return (EINVAL);
2136 
2137 	/*
2138 	 * check for forced unmount
2139 	 */
2140 	if (ufsvfsp == NULL)
2141 		return (EIO);
2142 
2143 	fs = ufsvfsp->vfs_fs;
2144 	if (fs->fs_ronly != 0)
2145 		return (EROFS);
2146 
2147 again:
2148 	errmsg1 = NULL;
2149 	errmsg2 = NULL;
2150 	dotrans = 0;
2151 	dorwlock = 0;
2152 	dodqlock = 0;
2153 
2154 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SETATTR_MASK);
2155 	if (error)
2156 		goto out;
2157 
2158 	/*
2159 	 * Acquire i_rwlock before TRANS_BEGIN_CSYNC() if this is a file.
2160 	 * This follows the protocol for read()/write().
2161 	 */
2162 	if (vp->v_type != VDIR) {
2163 		/*
2164 		 * ufs_tryirwlock uses rw_tryenter and checks for SLOCK to
2165 		 * avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
2166 		 * possible, retries the operation.
2167 		 */
2168 		ufs_tryirwlock(&ip->i_rwlock, RW_WRITER, retry_file);
2169 		if (indeadlock) {
2170 			if (ulp)
2171 				ufs_lockfs_end(ulp);
2172 			goto again;
2173 		}
2174 		dorwlock = 1;
2175 	}
2176 
2177 	/*
2178 	 * Truncate file.  Must have write permission and not be a directory.
2179 	 */
2180 	if (mask & AT_SIZE) {
2181 		rw_enter(&ip->i_contents, RW_WRITER);
2182 		if (vp->v_type == VDIR) {
2183 			error = EISDIR;
2184 			goto update_inode;
2185 		}
2186 		if (error = ufs_iaccess(ip, IWRITE, cr, 0))
2187 			goto update_inode;
2188 
2189 		rw_exit(&ip->i_contents);
2190 		error = TRANS_ITRUNC(ip, vap->va_size, 0, cr);
2191 		if (error) {
2192 			rw_enter(&ip->i_contents, RW_WRITER);
2193 			goto update_inode;
2194 		}
2195 
2196 		if (error == 0 && vap->va_size)
2197 			vnevent_truncate(vp, ct);
2198 	}
2199 
2200 	if (ulp) {
2201 		trans_size = (int)TOP_SETATTR_SIZE(ip);
2202 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_SETATTR, trans_size);
2203 		++dotrans;
2204 	}
2205 
2206 	/*
2207 	 * Acquire i_rwlock after TRANS_BEGIN_CSYNC() if this is a directory.
2208 	 * This follows the protocol established by
2209 	 * ufs_link/create/remove/rename/mkdir/rmdir/symlink.
2210 	 */
2211 	if (vp->v_type == VDIR) {
2212 		ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_SETATTR,
2213 		    retry_dir);
2214 		if (indeadlock)
2215 			goto again;
2216 		dorwlock = 1;
2217 	}
2218 
2219 	/*
2220 	 * Grab quota lock if we are changing the file's owner.
2221 	 */
2222 	if (mask & AT_UID) {
2223 		rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
2224 		dodqlock = 1;
2225 	}
2226 	rw_enter(&ip->i_contents, RW_WRITER);
2227 
2228 	oldva.va_mode = ip->i_mode;
2229 	oldva.va_uid = ip->i_uid;
2230 	oldva.va_gid = ip->i_gid;
2231 
2232 	vap->va_mask &= ~AT_SIZE;
2233 
2234 	error = secpolicy_vnode_setattr(cr, vp, vap, &oldva, flags,
2235 	    ufs_priv_access, ip);
2236 	if (error)
2237 		goto update_inode;
2238 
2239 	mask = vap->va_mask;
2240 
2241 	/*
2242 	 * Change file access modes.
2243 	 */
2244 	if (mask & AT_MODE) {
2245 		ip->i_mode = (ip->i_mode & IFMT) | (vap->va_mode & ~IFMT);
2246 		TRANS_INODE(ufsvfsp, ip);
2247 		ip->i_flag |= ICHG;
2248 		if (stickyhack) {
2249 			mutex_enter(&vp->v_lock);
2250 			if ((ip->i_mode & (ISVTX | IEXEC | IFDIR)) == ISVTX)
2251 				vp->v_flag |= VSWAPLIKE;
2252 			else
2253 				vp->v_flag &= ~VSWAPLIKE;
2254 			mutex_exit(&vp->v_lock);
2255 		}
2256 	}
2257 	if (mask & (AT_UID|AT_GID)) {
2258 		if (mask & AT_UID) {
2259 			/*
2260 			 * Don't change ownership of the quota inode.
2261 			 */
2262 			if (ufsvfsp->vfs_qinod == ip) {
2263 				ASSERT(ufsvfsp->vfs_qflags & MQ_ENABLED);
2264 				error = EINVAL;
2265 				goto update_inode;
2266 			}
2267 
2268 			/*
2269 			 * No real ownership change.
2270 			 */
2271 			if (ip->i_uid == vap->va_uid) {
2272 				blocks = 0;
2273 				owner_change = 0;
2274 			}
2275 			/*
2276 			 * Remove the blocks and the file, from the old user's
2277 			 * quota.
2278 			 */
2279 			else {
2280 				blocks = ip->i_blocks;
2281 				owner_change = 1;
2282 
2283 				(void) chkdq(ip, -blocks, /* force */ 1, cr,
2284 				    (char **)NULL, (size_t *)NULL);
2285 				(void) chkiq(ufsvfsp, /* change */ -1, ip,
2286 				    (uid_t)ip->i_uid, /* force */ 1, cr,
2287 				    (char **)NULL, (size_t *)NULL);
2288 				dqrele(ip->i_dquot);
2289 			}
2290 
2291 			ip->i_uid = vap->va_uid;
2292 
2293 			/*
2294 			 * There is a real ownership change.
2295 			 */
2296 			if (owner_change) {
2297 				/*
2298 				 * Add the blocks and the file to the new
2299 				 * user's quota.
2300 				 */
2301 				ip->i_dquot = getinoquota(ip);
2302 				(void) chkdq(ip, blocks, /* force */ 1, cr,
2303 				    &errmsg1, &len1);
2304 				(void) chkiq(ufsvfsp, /* change */ 1,
2305 				    (struct inode *)NULL, (uid_t)ip->i_uid,
2306 				    /* force */ 1, cr, &errmsg2, &len2);
2307 			}
2308 		}
2309 		if (mask & AT_GID) {
2310 			ip->i_gid = vap->va_gid;
2311 		}
2312 		TRANS_INODE(ufsvfsp, ip);
2313 		ip->i_flag |= ICHG;
2314 	}
2315 	/*
2316 	 * Change file access or modified times.
2317 	 */
2318 	if (mask & (AT_ATIME|AT_MTIME)) {
2319 		/* Check that the time value is within ufs range */
2320 		if (((mask & AT_ATIME) && TIMESPEC_OVERFLOW(&vap->va_atime)) ||
2321 		    ((mask & AT_MTIME) && TIMESPEC_OVERFLOW(&vap->va_mtime))) {
2322 			error = EOVERFLOW;
2323 			goto update_inode;
2324 		}
2325 
2326 		/*
2327 		 * if the "noaccess" mount option is set and only atime
2328 		 * update is requested, do nothing. No error is returned.
2329 		 */
2330 		if ((ufsvfsp->vfs_noatime) &&
2331 		    ((mask & (AT_ATIME|AT_MTIME)) == AT_ATIME))
2332 			goto skip_atime;
2333 
2334 		if (mask & AT_ATIME) {
2335 			ip->i_atime.tv_sec = vap->va_atime.tv_sec;
2336 			ip->i_atime.tv_usec = vap->va_atime.tv_nsec / 1000;
2337 			ip->i_flag &= ~IACC;
2338 		}
2339 		if (mask & AT_MTIME) {
2340 			ip->i_mtime.tv_sec = vap->va_mtime.tv_sec;
2341 			ip->i_mtime.tv_usec = vap->va_mtime.tv_nsec / 1000;
2342 			gethrestime(&now);
2343 			if (now.tv_sec > TIME32_MAX) {
2344 				/*
2345 				 * In 2038, ctime sticks forever..
2346 				 */
2347 				ip->i_ctime.tv_sec = TIME32_MAX;
2348 				ip->i_ctime.tv_usec = 0;
2349 			} else {
2350 				ip->i_ctime.tv_sec = now.tv_sec;
2351 				ip->i_ctime.tv_usec = now.tv_nsec / 1000;
2352 			}
2353 			ip->i_flag &= ~(IUPD|ICHG);
2354 			ip->i_flag |= IMODTIME;
2355 		}
2356 		TRANS_INODE(ufsvfsp, ip);
2357 		ip->i_flag |= IMOD;
2358 	}
2359 
2360 skip_atime:
2361 	/*
2362 	 * The presence of a shadow inode may indicate an ACL, but does
2363 	 * not imply an ACL.  Future FSD types should be handled here too
2364 	 * and check for the presence of the attribute-specific data
2365 	 * before referencing it.
2366 	 */
2367 	if (ip->i_shadow) {
2368 		/*
2369 		 * XXX if ufs_iupdat is changed to sandbagged write fix
2370 		 * ufs_acl_setattr to push ip to keep acls consistent
2371 		 *
2372 		 * Suppress out of inodes messages if we will retry.
2373 		 */
2374 		if (retry)
2375 			ip->i_flag |= IQUIET;
2376 		error = ufs_acl_setattr(ip, vap, cr);
2377 		ip->i_flag &= ~IQUIET;
2378 	}
2379 
2380 update_inode:
2381 	/*
2382 	 * Setattr always increases the sequence number
2383 	 */
2384 	ip->i_seq++;
2385 
2386 	/*
2387 	 * if nfsd and not logging; push synchronously
2388 	 */
2389 	if ((curthread->t_flag & T_DONTPEND) && !TRANS_ISTRANS(ufsvfsp)) {
2390 		ufs_iupdat(ip, 1);
2391 	} else {
2392 		ITIMES_NOLOCK(ip);
2393 	}
2394 
2395 	rw_exit(&ip->i_contents);
2396 	if (dodqlock) {
2397 		rw_exit(&ufsvfsp->vfs_dqrwlock);
2398 	}
2399 	if (dorwlock)
2400 		rw_exit(&ip->i_rwlock);
2401 
2402 	if (ulp) {
2403 		if (dotrans) {
2404 			int terr = 0;
2405 			TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_SETATTR,
2406 			    trans_size);
2407 			if (error == 0)
2408 				error = terr;
2409 		}
2410 		ufs_lockfs_end(ulp);
2411 	}
2412 out:
2413 	/*
2414 	 * If out of inodes or blocks, see if we can free something
2415 	 * up from the delete queue.
2416 	 */
2417 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
2418 		ufs_delete_drain_wait(ufsvfsp, 1);
2419 		retry = 0;
2420 		if (errmsg1 != NULL)
2421 			kmem_free(errmsg1, len1);
2422 		if (errmsg2 != NULL)
2423 			kmem_free(errmsg2, len2);
2424 		goto again;
2425 	}
2426 	if (errmsg1 != NULL) {
2427 		uprintf(errmsg1);
2428 		kmem_free(errmsg1, len1);
2429 	}
2430 	if (errmsg2 != NULL) {
2431 		uprintf(errmsg2);
2432 		kmem_free(errmsg2, len2);
2433 	}
2434 	return (error);
2435 }
2436 
2437 /*ARGSUSED*/
2438 static int
ufs_access(struct vnode * vp,int mode,int flags,struct cred * cr,caller_context_t * ct)2439 ufs_access(struct vnode *vp, int mode, int flags, struct cred *cr,
2440 	caller_context_t *ct)
2441 {
2442 	struct inode *ip = VTOI(vp);
2443 
2444 	if (ip->i_ufsvfs == NULL)
2445 		return (EIO);
2446 
2447 	/*
2448 	 * The ufs_iaccess function wants to be called with
2449 	 * mode bits expressed as "ufs specific" bits.
2450 	 * I.e., VWRITE|VREAD|VEXEC do not make sense to
2451 	 * ufs_iaccess() but IWRITE|IREAD|IEXEC do.
2452 	 * But since they're the same we just pass the vnode mode
2453 	 * bit but just verify that assumption at compile time.
2454 	 */
2455 #if IWRITE != VWRITE || IREAD != VREAD || IEXEC != VEXEC
2456 #error "ufs_access needs to map Vmodes to Imodes"
2457 #endif
2458 	return (ufs_iaccess(ip, mode, cr, 1));
2459 }
2460 
2461 /* ARGSUSED */
2462 static int
ufs_readlink(struct vnode * vp,struct uio * uiop,struct cred * cr,caller_context_t * ct)2463 ufs_readlink(struct vnode *vp, struct uio *uiop, struct cred *cr,
2464 	caller_context_t *ct)
2465 {
2466 	struct inode *ip = VTOI(vp);
2467 	struct ufsvfs *ufsvfsp;
2468 	struct ulockfs *ulp;
2469 	int error;
2470 	int fastsymlink;
2471 
2472 	if (vp->v_type != VLNK) {
2473 		error = EINVAL;
2474 		goto nolockout;
2475 	}
2476 
2477 	/*
2478 	 * If the symbolic link is empty there is nothing to read.
2479 	 * Fast-track these empty symbolic links
2480 	 */
2481 	if (ip->i_size == 0) {
2482 		error = 0;
2483 		goto nolockout;
2484 	}
2485 
2486 	ufsvfsp = ip->i_ufsvfs;
2487 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_READLINK_MASK);
2488 	if (error)
2489 		goto nolockout;
2490 	/*
2491 	 * The ip->i_rwlock protects the data blocks used for FASTSYMLINK
2492 	 */
2493 again:
2494 	fastsymlink = 0;
2495 	if (ip->i_flag & IFASTSYMLNK) {
2496 		rw_enter(&ip->i_rwlock, RW_READER);
2497 		rw_enter(&ip->i_contents, RW_READER);
2498 		if (ip->i_flag & IFASTSYMLNK) {
2499 			if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) &&
2500 			    (ip->i_fs->fs_ronly == 0) &&
2501 			    (!ufsvfsp->vfs_noatime)) {
2502 				mutex_enter(&ip->i_tlock);
2503 				ip->i_flag |= IACC;
2504 				mutex_exit(&ip->i_tlock);
2505 			}
2506 			error = uiomove((caddr_t)&ip->i_db[1],
2507 			    MIN(ip->i_size, uiop->uio_resid),
2508 			    UIO_READ, uiop);
2509 			ITIMES(ip);
2510 			++fastsymlink;
2511 		}
2512 		rw_exit(&ip->i_contents);
2513 		rw_exit(&ip->i_rwlock);
2514 	}
2515 	if (!fastsymlink) {
2516 		ssize_t size;	/* number of bytes read  */
2517 		caddr_t basep;	/* pointer to input data */
2518 		ino_t ino;
2519 		long  igen;
2520 		struct uio tuio;	/* temp uio struct */
2521 		struct uio *tuiop;
2522 		iovec_t tiov;		/* temp iovec struct */
2523 		char kbuf[FSL_SIZE];	/* buffer to hold fast symlink */
2524 		int tflag = 0;		/* flag to indicate temp vars used */
2525 
2526 		ino = ip->i_number;
2527 		igen = ip->i_gen;
2528 		size = uiop->uio_resid;
2529 		basep = uiop->uio_iov->iov_base;
2530 		tuiop = uiop;
2531 
2532 		rw_enter(&ip->i_rwlock, RW_WRITER);
2533 		rw_enter(&ip->i_contents, RW_WRITER);
2534 		if (ip->i_flag & IFASTSYMLNK) {
2535 			rw_exit(&ip->i_contents);
2536 			rw_exit(&ip->i_rwlock);
2537 			goto again;
2538 		}
2539 
2540 		/* can this be a fast symlink and is it a user buffer? */
2541 		if (ip->i_size <= FSL_SIZE &&
2542 		    (uiop->uio_segflg == UIO_USERSPACE ||
2543 		    uiop->uio_segflg == UIO_USERISPACE)) {
2544 
2545 			bzero(&tuio, sizeof (struct uio));
2546 			/*
2547 			 * setup a kernel buffer to read link into.  this
2548 			 * is to fix a race condition where the user buffer
2549 			 * got corrupted before copying it into the inode.
2550 			 */
2551 			size = ip->i_size;
2552 			tiov.iov_len = size;
2553 			tiov.iov_base = kbuf;
2554 			tuio.uio_iov = &tiov;
2555 			tuio.uio_iovcnt = 1;
2556 			tuio.uio_offset = uiop->uio_offset;
2557 			tuio.uio_segflg = UIO_SYSSPACE;
2558 			tuio.uio_fmode = uiop->uio_fmode;
2559 			tuio.uio_extflg = uiop->uio_extflg;
2560 			tuio.uio_limit = uiop->uio_limit;
2561 			tuio.uio_resid = size;
2562 
2563 			basep = tuio.uio_iov->iov_base;
2564 			tuiop = &tuio;
2565 			tflag = 1;
2566 		}
2567 
2568 		error = rdip(ip, tuiop, 0, cr);
2569 		if (!(error == 0 && ip->i_number == ino && ip->i_gen == igen)) {
2570 			rw_exit(&ip->i_contents);
2571 			rw_exit(&ip->i_rwlock);
2572 			goto out;
2573 		}
2574 
2575 		if (tflag == 0)
2576 			size -= uiop->uio_resid;
2577 
2578 		if ((tflag == 0 && ip->i_size <= FSL_SIZE &&
2579 		    ip->i_size == size) || (tflag == 1 &&
2580 		    tuio.uio_resid == 0)) {
2581 			error = kcopy(basep, &ip->i_db[1], ip->i_size);
2582 			if (error == 0) {
2583 				ip->i_flag |= IFASTSYMLNK;
2584 				/*
2585 				 * free page
2586 				 */
2587 				(void) VOP_PUTPAGE(ITOV(ip),
2588 				    (offset_t)0, PAGESIZE,
2589 				    (B_DONTNEED | B_FREE | B_FORCE | B_ASYNC),
2590 				    cr, ct);
2591 			} else {
2592 				int i;
2593 				/* error, clear garbage left behind */
2594 				for (i = 1; i < NDADDR; i++)
2595 					ip->i_db[i] = 0;
2596 				for (i = 0; i < NIADDR; i++)
2597 					ip->i_ib[i] = 0;
2598 			}
2599 		}
2600 		if (tflag == 1) {
2601 			/* now, copy it into the user buffer */
2602 			error = uiomove((caddr_t)kbuf,
2603 			    MIN(size, uiop->uio_resid),
2604 			    UIO_READ, uiop);
2605 		}
2606 		rw_exit(&ip->i_contents);
2607 		rw_exit(&ip->i_rwlock);
2608 	}
2609 out:
2610 	if (ulp) {
2611 		ufs_lockfs_end(ulp);
2612 	}
2613 nolockout:
2614 	return (error);
2615 }
2616 
2617 /* ARGSUSED */
2618 static int
ufs_fsync(struct vnode * vp,int syncflag,struct cred * cr,caller_context_t * ct)2619 ufs_fsync(struct vnode *vp, int syncflag, struct cred *cr,
2620 	caller_context_t *ct)
2621 {
2622 	struct inode *ip = VTOI(vp);
2623 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
2624 	struct ulockfs *ulp;
2625 	int error;
2626 
2627 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_FSYNC_MASK);
2628 	if (error)
2629 		return (error);
2630 
2631 	if (TRANS_ISTRANS(ufsvfsp)) {
2632 		/*
2633 		 * First push out any data pages
2634 		 */
2635 		if (vn_has_cached_data(vp) && !(syncflag & FNODSYNC) &&
2636 		    (vp->v_type != VCHR) && !(IS_SWAPVP(vp))) {
2637 			error = VOP_PUTPAGE(vp, (offset_t)0, (size_t)0,
2638 			    0, CRED(), ct);
2639 			if (error)
2640 				goto out;
2641 		}
2642 
2643 		/*
2644 		 * Delta any delayed inode times updates
2645 		 * and push inode to log.
2646 		 * All other inode deltas will have already been delta'd
2647 		 * and will be pushed during the commit.
2648 		 */
2649 		if (!(syncflag & FDSYNC) &&
2650 		    ((ip->i_flag & (IMOD|IMODACC)) == IMODACC)) {
2651 			if (ulp) {
2652 				TRANS_BEGIN_ASYNC(ufsvfsp, TOP_FSYNC,
2653 				    TOP_SYNCIP_SIZE);
2654 			}
2655 			rw_enter(&ip->i_contents, RW_READER);
2656 			mutex_enter(&ip->i_tlock);
2657 			ip->i_flag &= ~IMODTIME;
2658 			mutex_exit(&ip->i_tlock);
2659 			ufs_iupdat(ip, I_SYNC);
2660 			rw_exit(&ip->i_contents);
2661 			if (ulp) {
2662 				TRANS_END_ASYNC(ufsvfsp, TOP_FSYNC,
2663 				    TOP_SYNCIP_SIZE);
2664 			}
2665 		}
2666 
2667 		/*
2668 		 * Commit the Moby transaction
2669 		 *
2670 		 * Deltas have already been made so we just need to
2671 		 * commit them with a synchronous transaction.
2672 		 * TRANS_BEGIN_SYNC() will return an error
2673 		 * if there are no deltas to commit, for an
2674 		 * empty transaction.
2675 		 */
2676 		if (ulp) {
2677 			TRANS_BEGIN_SYNC(ufsvfsp, TOP_FSYNC, TOP_COMMIT_SIZE,
2678 			    error);
2679 			if (error) {
2680 				error = 0; /* commit wasn't needed */
2681 				goto out;
2682 			}
2683 			TRANS_END_SYNC(ufsvfsp, error, TOP_FSYNC,
2684 			    TOP_COMMIT_SIZE);
2685 		}
2686 	} else {	/* not logging */
2687 		if (!(IS_SWAPVP(vp)))
2688 			if (syncflag & FNODSYNC) {
2689 				/* Just update the inode only */
2690 				TRANS_IUPDAT(ip, 1);
2691 				error = 0;
2692 			} else if (syncflag & FDSYNC)
2693 				/* Do data-synchronous writes */
2694 				error = TRANS_SYNCIP(ip, 0, I_DSYNC, TOP_FSYNC);
2695 			else
2696 				/* Do synchronous writes */
2697 				error = TRANS_SYNCIP(ip, 0, I_SYNC, TOP_FSYNC);
2698 
2699 		rw_enter(&ip->i_contents, RW_WRITER);
2700 		if (!error)
2701 			error = ufs_sync_indir(ip);
2702 		rw_exit(&ip->i_contents);
2703 	}
2704 out:
2705 	if (ulp) {
2706 		ufs_lockfs_end(ulp);
2707 	}
2708 	return (error);
2709 }
2710 
2711 /*ARGSUSED*/
2712 static void
ufs_inactive(struct vnode * vp,struct cred * cr,caller_context_t * ct)2713 ufs_inactive(struct vnode *vp, struct cred *cr, caller_context_t *ct)
2714 {
2715 	ufs_iinactive(VTOI(vp));
2716 }
2717 
2718 /*
2719  * Unix file system operations having to do with directory manipulation.
2720  */
2721 int ufs_lookup_idle_count = 2;	/* Number of inodes to idle each time */
2722 /* ARGSUSED */
2723 static int
ufs_lookup(struct vnode * dvp,char * nm,struct vnode ** vpp,struct pathname * pnp,int flags,struct vnode * rdir,struct cred * cr,caller_context_t * ct,int * direntflags,pathname_t * realpnp)2724 ufs_lookup(struct vnode *dvp, char *nm, struct vnode **vpp,
2725 	struct pathname *pnp, int flags, struct vnode *rdir, struct cred *cr,
2726 	caller_context_t *ct, int *direntflags, pathname_t *realpnp)
2727 {
2728 	struct inode *ip;
2729 	struct inode *sip;
2730 	struct inode *xip;
2731 	struct ufsvfs *ufsvfsp;
2732 	struct ulockfs *ulp;
2733 	struct vnode *vp;
2734 	int error;
2735 
2736 	/*
2737 	 * Check flags for type of lookup (regular file or attribute file)
2738 	 */
2739 
2740 	ip = VTOI(dvp);
2741 
2742 	if (flags & LOOKUP_XATTR) {
2743 
2744 		/*
2745 		 * If not mounted with XATTR support then return EINVAL
2746 		 */
2747 
2748 		if (!(ip->i_ufsvfs->vfs_vfs->vfs_flag & VFS_XATTR))
2749 			return (EINVAL);
2750 		/*
2751 		 * We don't allow recursive attributes...
2752 		 * Maybe someday we will.
2753 		 */
2754 		if ((ip->i_cflags & IXATTR)) {
2755 			return (EINVAL);
2756 		}
2757 
2758 		if ((vp = dnlc_lookup(dvp, XATTR_DIR_NAME)) == NULL) {
2759 			error = ufs_xattr_getattrdir(dvp, &sip, flags, cr);
2760 			if (error) {
2761 				*vpp = NULL;
2762 				goto out;
2763 			}
2764 
2765 			vp = ITOV(sip);
2766 			dnlc_update(dvp, XATTR_DIR_NAME, vp);
2767 		}
2768 
2769 		/*
2770 		 * Check accessibility of directory.
2771 		 */
2772 		if (vp == DNLC_NO_VNODE) {
2773 			VN_RELE(vp);
2774 			error = ENOENT;
2775 			goto out;
2776 		}
2777 		if ((error = ufs_iaccess(VTOI(vp), IEXEC, cr, 1)) != 0) {
2778 			VN_RELE(vp);
2779 			goto out;
2780 		}
2781 
2782 		*vpp = vp;
2783 		return (0);
2784 	}
2785 
2786 	/*
2787 	 * Check for a null component, which we should treat as
2788 	 * looking at dvp from within it's parent, so we don't
2789 	 * need a call to ufs_iaccess(), as it has already been
2790 	 * done.
2791 	 */
2792 	if (nm[0] == 0) {
2793 		VN_HOLD(dvp);
2794 		error = 0;
2795 		*vpp = dvp;
2796 		goto out;
2797 	}
2798 
2799 	/*
2800 	 * Check for "." ie itself. this is a quick check and
2801 	 * avoids adding "." into the dnlc (which have been seen
2802 	 * to occupy >10% of the cache).
2803 	 */
2804 	if ((nm[0] == '.') && (nm[1] == 0)) {
2805 		/*
2806 		 * Don't return without checking accessibility
2807 		 * of the directory. We only need the lock if
2808 		 * we are going to return it.
2809 		 */
2810 		if ((error = ufs_iaccess(ip, IEXEC, cr, 1)) == 0) {
2811 			VN_HOLD(dvp);
2812 			*vpp = dvp;
2813 		}
2814 		goto out;
2815 	}
2816 
2817 	/*
2818 	 * Fast path: Check the directory name lookup cache.
2819 	 */
2820 	if (vp = dnlc_lookup(dvp, nm)) {
2821 		/*
2822 		 * Check accessibility of directory.
2823 		 */
2824 		if ((error = ufs_iaccess(ip, IEXEC, cr, 1)) != 0) {
2825 			VN_RELE(vp);
2826 			goto out;
2827 		}
2828 		if (vp == DNLC_NO_VNODE) {
2829 			VN_RELE(vp);
2830 			error = ENOENT;
2831 			goto out;
2832 		}
2833 		xip = VTOI(vp);
2834 		ulp = NULL;
2835 		goto fastpath;
2836 	}
2837 
2838 	/*
2839 	 * Keep the idle queue from getting too long by
2840 	 * idling two inodes before attempting to allocate another.
2841 	 *    This operation must be performed before entering
2842 	 *    lockfs or a transaction.
2843 	 */
2844 	if (ufs_idle_q.uq_ne > ufs_idle_q.uq_hiwat)
2845 		if ((curthread->t_flag & T_DONTBLOCK) == 0) {
2846 			ins.in_lidles.value.ul += ufs_lookup_idle_count;
2847 			ufs_idle_some(ufs_lookup_idle_count);
2848 		}
2849 
2850 retry_lookup:
2851 	/*
2852 	 * Check accessibility of directory.
2853 	 */
2854 	if (error = ufs_diraccess(ip, IEXEC, cr))
2855 		goto out;
2856 
2857 	ufsvfsp = ip->i_ufsvfs;
2858 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LOOKUP_MASK);
2859 	if (error)
2860 		goto out;
2861 
2862 	error = ufs_dirlook(ip, nm, &xip, cr, 1, 0);
2863 
2864 fastpath:
2865 	if (error == 0) {
2866 		ip = xip;
2867 		*vpp = ITOV(ip);
2868 
2869 		/*
2870 		 * If vnode is a device return special vnode instead.
2871 		 */
2872 		if (IS_DEVVP(*vpp)) {
2873 			struct vnode *newvp;
2874 
2875 			newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type,
2876 			    cr);
2877 			VN_RELE(*vpp);
2878 			if (newvp == NULL)
2879 				error = ENOSYS;
2880 			else
2881 				*vpp = newvp;
2882 		} else if (ip->i_cflags & ICOMPRESS) {
2883 			struct vnode *newvp;
2884 
2885 			/*
2886 			 * Compressed file, substitute dcfs vnode
2887 			 */
2888 			newvp = decompvp(*vpp, cr, ct);
2889 			VN_RELE(*vpp);
2890 			if (newvp == NULL)
2891 				error = ENOSYS;
2892 			else
2893 				*vpp = newvp;
2894 		}
2895 	}
2896 	if (ulp) {
2897 		ufs_lockfs_end(ulp);
2898 	}
2899 
2900 	if (error == EAGAIN)
2901 		goto retry_lookup;
2902 
2903 out:
2904 	return (error);
2905 }
2906 
2907 /*ARGSUSED*/
2908 static int
ufs_create(struct vnode * dvp,char * name,struct vattr * vap,enum vcexcl excl,int mode,struct vnode ** vpp,struct cred * cr,int flag,caller_context_t * ct,vsecattr_t * vsecp)2909 ufs_create(struct vnode *dvp, char *name, struct vattr *vap, enum vcexcl excl,
2910 	int mode, struct vnode **vpp, struct cred *cr, int flag,
2911 	caller_context_t *ct, vsecattr_t *vsecp)
2912 {
2913 	struct inode *ip;
2914 	struct inode *xip;
2915 	struct inode *dip;
2916 	struct vnode *xvp;
2917 	struct ufsvfs *ufsvfsp;
2918 	struct ulockfs *ulp;
2919 	int error;
2920 	int issync;
2921 	int truncflag;
2922 	int trans_size;
2923 	int noentry;
2924 	int defer_dip_seq_update = 0;	/* need to defer update of dip->i_seq */
2925 	int retry = 1;
2926 	int indeadlock;
2927 
2928 again:
2929 	ip = VTOI(dvp);
2930 	ufsvfsp = ip->i_ufsvfs;
2931 	truncflag = 0;
2932 
2933 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_CREATE_MASK);
2934 	if (error)
2935 		goto out;
2936 
2937 	if (ulp) {
2938 		trans_size = (int)TOP_CREATE_SIZE(ip);
2939 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_CREATE, trans_size);
2940 	}
2941 
2942 	if ((vap->va_mode & VSVTX) && secpolicy_vnode_stky_modify(cr) != 0)
2943 		vap->va_mode &= ~VSVTX;
2944 
2945 	if (*name == '\0') {
2946 		/*
2947 		 * Null component name refers to the directory itself.
2948 		 */
2949 		VN_HOLD(dvp);
2950 		/*
2951 		 * Even though this is an error case, we need to grab the
2952 		 * quota lock since the error handling code below is common.
2953 		 */
2954 		rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
2955 		rw_enter(&ip->i_contents, RW_WRITER);
2956 		error = EEXIST;
2957 	} else {
2958 		xip = NULL;
2959 		noentry = 0;
2960 		/*
2961 		 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
2962 		 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
2963 		 * possible, retries the operation.
2964 		 */
2965 		ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_CREATE,
2966 		    retry_dir);
2967 		if (indeadlock)
2968 			goto again;
2969 
2970 		xvp = dnlc_lookup(dvp, name);
2971 		if (xvp == DNLC_NO_VNODE) {
2972 			noentry = 1;
2973 			VN_RELE(xvp);
2974 			xvp = NULL;
2975 		}
2976 		if (xvp) {
2977 			rw_exit(&ip->i_rwlock);
2978 			if (error = ufs_iaccess(ip, IEXEC, cr, 1)) {
2979 				VN_RELE(xvp);
2980 			} else {
2981 				error = EEXIST;
2982 				xip = VTOI(xvp);
2983 			}
2984 		} else {
2985 			/*
2986 			 * Suppress file system full message if we will retry
2987 			 */
2988 			error = ufs_direnter_cm(ip, name, DE_CREATE,
2989 			    vap, &xip, cr, (noentry | (retry ? IQUIET : 0)));
2990 			if (error == EAGAIN) {
2991 				if (ulp) {
2992 					TRANS_END_CSYNC(ufsvfsp, error, issync,
2993 					    TOP_CREATE, trans_size);
2994 					ufs_lockfs_end(ulp);
2995 				}
2996 				goto again;
2997 			}
2998 			rw_exit(&ip->i_rwlock);
2999 		}
3000 		ip = xip;
3001 		if (ip != NULL) {
3002 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
3003 			rw_enter(&ip->i_contents, RW_WRITER);
3004 		}
3005 	}
3006 
3007 	/*
3008 	 * If the file already exists and this is a non-exclusive create,
3009 	 * check permissions and allow access for non-directories.
3010 	 * Read-only create of an existing directory is also allowed.
3011 	 * We fail an exclusive create of anything which already exists.
3012 	 */
3013 	if (error == EEXIST) {
3014 		dip = VTOI(dvp);
3015 		if (excl == NONEXCL) {
3016 			if ((((ip->i_mode & IFMT) == IFDIR) ||
3017 			    ((ip->i_mode & IFMT) == IFATTRDIR)) &&
3018 			    (mode & IWRITE))
3019 				error = EISDIR;
3020 			else if (mode)
3021 				error = ufs_iaccess(ip, mode, cr, 0);
3022 			else
3023 				error = 0;
3024 		}
3025 		if (error) {
3026 			rw_exit(&ip->i_contents);
3027 			rw_exit(&ufsvfsp->vfs_dqrwlock);
3028 			VN_RELE(ITOV(ip));
3029 			goto unlock;
3030 		}
3031 		/*
3032 		 * If the error EEXIST was set, then i_seq can not
3033 		 * have been updated. The sequence number interface
3034 		 * is defined such that a non-error VOP_CREATE must
3035 		 * increase the dir va_seq it by at least one. If we
3036 		 * have cleared the error, increase i_seq. Note that
3037 		 * we are increasing the dir i_seq and in rare cases
3038 		 * ip may actually be from the dvp, so we already have
3039 		 * the locks and it will not be subject to truncation.
3040 		 * In case we have to update i_seq of the parent
3041 		 * directory dip, we have to defer it till we have
3042 		 * released our locks on ip due to lock ordering requirements.
3043 		 */
3044 		if (ip != dip)
3045 			defer_dip_seq_update = 1;
3046 		else
3047 			ip->i_seq++;
3048 
3049 		if (((ip->i_mode & IFMT) == IFREG) &&
3050 		    (vap->va_mask & AT_SIZE) && vap->va_size == 0) {
3051 			/*
3052 			 * Truncate regular files, if requested by caller.
3053 			 * Grab i_rwlock to make sure no one else is
3054 			 * currently writing to the file (we promised
3055 			 * bmap we would do this).
3056 			 * Must get the locks in the correct order.
3057 			 */
3058 			if (ip->i_size == 0) {
3059 				ip->i_flag |= ICHG | IUPD;
3060 				ip->i_seq++;
3061 				TRANS_INODE(ufsvfsp, ip);
3062 			} else {
3063 				/*
3064 				 * Large Files: Why this check here?
3065 				 * Though we do it in vn_create() we really
3066 				 * want to guarantee that we do not destroy
3067 				 * Large file data by atomically checking
3068 				 * the size while holding the contents
3069 				 * lock.
3070 				 */
3071 				if (flag && !(flag & FOFFMAX) &&
3072 				    ((ip->i_mode & IFMT) == IFREG) &&
3073 				    (ip->i_size > (offset_t)MAXOFF32_T)) {
3074 					rw_exit(&ip->i_contents);
3075 					rw_exit(&ufsvfsp->vfs_dqrwlock);
3076 					error = EOVERFLOW;
3077 					goto unlock;
3078 				}
3079 				if (TRANS_ISTRANS(ufsvfsp))
3080 					truncflag++;
3081 				else {
3082 					rw_exit(&ip->i_contents);
3083 					rw_exit(&ufsvfsp->vfs_dqrwlock);
3084 					ufs_tryirwlock_trans(&ip->i_rwlock,
3085 					    RW_WRITER, TOP_CREATE,
3086 					    retry_file);
3087 					if (indeadlock) {
3088 						VN_RELE(ITOV(ip));
3089 						goto again;
3090 					}
3091 					rw_enter(&ufsvfsp->vfs_dqrwlock,
3092 					    RW_READER);
3093 					rw_enter(&ip->i_contents, RW_WRITER);
3094 					(void) ufs_itrunc(ip, (u_offset_t)0, 0,
3095 					    cr);
3096 					rw_exit(&ip->i_rwlock);
3097 				}
3098 
3099 			}
3100 			if (error == 0) {
3101 				vnevent_create(ITOV(ip), ct);
3102 			}
3103 		}
3104 	}
3105 
3106 	if (error) {
3107 		if (ip != NULL) {
3108 			rw_exit(&ufsvfsp->vfs_dqrwlock);
3109 			rw_exit(&ip->i_contents);
3110 		}
3111 		goto unlock;
3112 	}
3113 
3114 	*vpp = ITOV(ip);
3115 	ITIMES(ip);
3116 	rw_exit(&ip->i_contents);
3117 	rw_exit(&ufsvfsp->vfs_dqrwlock);
3118 
3119 	/*
3120 	 * If vnode is a device return special vnode instead.
3121 	 */
3122 	if (!error && IS_DEVVP(*vpp)) {
3123 		struct vnode *newvp;
3124 
3125 		newvp = specvp(*vpp, (*vpp)->v_rdev, (*vpp)->v_type, cr);
3126 		VN_RELE(*vpp);
3127 		if (newvp == NULL) {
3128 			error = ENOSYS;
3129 			goto unlock;
3130 		}
3131 		truncflag = 0;
3132 		*vpp = newvp;
3133 	}
3134 unlock:
3135 
3136 	/*
3137 	 * Do the deferred update of the parent directory's sequence
3138 	 * number now.
3139 	 */
3140 	if (defer_dip_seq_update == 1) {
3141 		rw_enter(&dip->i_contents, RW_READER);
3142 		mutex_enter(&dip->i_tlock);
3143 		dip->i_seq++;
3144 		mutex_exit(&dip->i_tlock);
3145 		rw_exit(&dip->i_contents);
3146 	}
3147 
3148 	if (ulp) {
3149 		int terr = 0;
3150 
3151 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_CREATE,
3152 		    trans_size);
3153 
3154 		/*
3155 		 * If we haven't had a more interesting failure
3156 		 * already, then anything that might've happened
3157 		 * here should be reported.
3158 		 */
3159 		if (error == 0)
3160 			error = terr;
3161 	}
3162 
3163 	if (!error && truncflag) {
3164 		ufs_tryirwlock(&ip->i_rwlock, RW_WRITER, retry_trunc);
3165 		if (indeadlock) {
3166 			if (ulp)
3167 				ufs_lockfs_end(ulp);
3168 			VN_RELE(ITOV(ip));
3169 			goto again;
3170 		}
3171 		(void) TRANS_ITRUNC(ip, (u_offset_t)0, 0, cr);
3172 		rw_exit(&ip->i_rwlock);
3173 	}
3174 
3175 	if (ulp)
3176 		ufs_lockfs_end(ulp);
3177 
3178 	/*
3179 	 * If no inodes available, try to free one up out of the
3180 	 * pending delete queue.
3181 	 */
3182 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
3183 		ufs_delete_drain_wait(ufsvfsp, 1);
3184 		retry = 0;
3185 		goto again;
3186 	}
3187 
3188 out:
3189 	return (error);
3190 }
3191 
3192 extern int ufs_idle_max;
3193 /*ARGSUSED*/
3194 static int
ufs_remove(struct vnode * vp,char * nm,struct cred * cr,caller_context_t * ct,int flags)3195 ufs_remove(struct vnode *vp, char *nm, struct cred *cr,
3196 	caller_context_t *ct, int flags)
3197 {
3198 	struct inode *ip = VTOI(vp);
3199 	struct ufsvfs *ufsvfsp	= ip->i_ufsvfs;
3200 	struct ulockfs *ulp;
3201 	vnode_t *rmvp = NULL;	/* Vnode corresponding to name being removed */
3202 	int indeadlock;
3203 	int error;
3204 	int issync;
3205 	int trans_size;
3206 
3207 	/*
3208 	 * don't let the delete queue get too long
3209 	 */
3210 	if (ufsvfsp == NULL) {
3211 		error = EIO;
3212 		goto out;
3213 	}
3214 	if (ufsvfsp->vfs_delete.uq_ne > ufs_idle_max)
3215 		ufs_delete_drain(vp->v_vfsp, 1, 1);
3216 
3217 	error = ufs_eventlookup(vp, nm, cr, &rmvp);
3218 	if (rmvp != NULL) {
3219 		/* Only send the event if there were no errors */
3220 		if (error == 0)
3221 			vnevent_remove(rmvp, vp, nm, ct);
3222 		VN_RELE(rmvp);
3223 	}
3224 
3225 retry_remove:
3226 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_REMOVE_MASK);
3227 	if (error)
3228 		goto out;
3229 
3230 	if (ulp)
3231 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_REMOVE,
3232 		    trans_size = (int)TOP_REMOVE_SIZE(VTOI(vp)));
3233 
3234 	/*
3235 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3236 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3237 	 * possible, retries the operation.
3238 	 */
3239 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_REMOVE, retry);
3240 	if (indeadlock)
3241 		goto retry_remove;
3242 	error = ufs_dirremove(ip, nm, (struct inode *)0, (struct vnode *)0,
3243 	    DR_REMOVE, cr);
3244 	rw_exit(&ip->i_rwlock);
3245 
3246 	if (ulp) {
3247 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_REMOVE, trans_size);
3248 		ufs_lockfs_end(ulp);
3249 	}
3250 
3251 out:
3252 	return (error);
3253 }
3254 
3255 /*
3256  * Link a file or a directory.  Only privileged processes are allowed to
3257  * make links to directories.
3258  */
3259 /*ARGSUSED*/
3260 static int
ufs_link(struct vnode * tdvp,struct vnode * svp,char * tnm,struct cred * cr,caller_context_t * ct,int flags)3261 ufs_link(struct vnode *tdvp, struct vnode *svp, char *tnm, struct cred *cr,
3262 	caller_context_t *ct, int flags)
3263 {
3264 	struct inode *sip;
3265 	struct inode *tdp = VTOI(tdvp);
3266 	struct ufsvfs *ufsvfsp = tdp->i_ufsvfs;
3267 	struct ulockfs *ulp;
3268 	struct vnode *realvp;
3269 	int error;
3270 	int issync;
3271 	int trans_size;
3272 	int isdev;
3273 	int indeadlock;
3274 
3275 retry_link:
3276 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LINK_MASK);
3277 	if (error)
3278 		goto out;
3279 
3280 	if (ulp)
3281 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_LINK,
3282 		    trans_size = (int)TOP_LINK_SIZE(VTOI(tdvp)));
3283 
3284 	if (VOP_REALVP(svp, &realvp, ct) == 0)
3285 		svp = realvp;
3286 
3287 	/*
3288 	 * Make sure link for extended attributes is valid
3289 	 * We only support hard linking of attr in ATTRDIR to ATTRDIR
3290 	 *
3291 	 * Make certain we don't attempt to look at a device node as
3292 	 * a ufs inode.
3293 	 */
3294 
3295 	isdev = IS_DEVVP(svp);
3296 	if (((isdev == 0) && ((VTOI(svp)->i_cflags & IXATTR) == 0) &&
3297 	    ((tdp->i_mode & IFMT) == IFATTRDIR)) ||
3298 	    ((isdev == 0) && (VTOI(svp)->i_cflags & IXATTR) &&
3299 	    ((tdp->i_mode & IFMT) == IFDIR))) {
3300 		error = EINVAL;
3301 		goto unlock;
3302 	}
3303 
3304 	sip = VTOI(svp);
3305 	if ((svp->v_type == VDIR &&
3306 	    secpolicy_fs_linkdir(cr, ufsvfsp->vfs_vfs) != 0) ||
3307 	    (sip->i_uid != crgetuid(cr) && secpolicy_basic_link(cr) != 0)) {
3308 		error = EPERM;
3309 		goto unlock;
3310 	}
3311 
3312 	/*
3313 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3314 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3315 	 * possible, retries the operation.
3316 	 */
3317 	ufs_tryirwlock_trans(&tdp->i_rwlock, RW_WRITER, TOP_LINK, retry);
3318 	if (indeadlock)
3319 		goto retry_link;
3320 	error = ufs_direnter_lr(tdp, tnm, DE_LINK, (struct inode *)0,
3321 	    sip, cr);
3322 	rw_exit(&tdp->i_rwlock);
3323 
3324 unlock:
3325 	if (ulp) {
3326 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_LINK, trans_size);
3327 		ufs_lockfs_end(ulp);
3328 	}
3329 
3330 	if (!error) {
3331 		vnevent_link(svp, ct);
3332 	}
3333 out:
3334 	return (error);
3335 }
3336 
3337 uint64_t ufs_rename_retry_cnt;
3338 uint64_t ufs_rename_upgrade_retry_cnt;
3339 uint64_t ufs_rename_dircheck_retry_cnt;
3340 clock_t	 ufs_rename_backoff_delay = 1;
3341 
3342 /*
3343  * Rename a file or directory.
3344  * We are given the vnode and entry string of the source and the
3345  * vnode and entry string of the place we want to move the source
3346  * to (the target). The essential operation is:
3347  *	unlink(target);
3348  *	link(source, target);
3349  *	unlink(source);
3350  * but "atomically".  Can't do full commit without saving state in
3351  * the inode on disk, which isn't feasible at this time.  Best we
3352  * can do is always guarantee that the TARGET exists.
3353  */
3354 
3355 /*ARGSUSED*/
3356 static int
ufs_rename(struct vnode * sdvp,char * snm,struct vnode * tdvp,char * tnm,struct cred * cr,caller_context_t * ct,int flags)3357 ufs_rename(
3358 	struct vnode *sdvp,		/* old (source) parent vnode */
3359 	char *snm,			/* old (source) entry name */
3360 	struct vnode *tdvp,		/* new (target) parent vnode */
3361 	char *tnm,			/* new (target) entry name */
3362 	struct cred *cr,
3363 	caller_context_t *ct,
3364 	int flags)
3365 {
3366 	struct inode *sip = NULL;	/* source inode */
3367 	struct inode *ip = NULL;	/* check inode */
3368 	struct inode *sdp;		/* old (source) parent inode */
3369 	struct inode *tdp;		/* new (target) parent inode */
3370 	struct vnode *svp = NULL;	/* source vnode */
3371 	struct vnode *tvp = NULL;	/* target vnode, if it exists */
3372 	struct vnode *realvp;
3373 	struct ufsvfs *ufsvfsp;
3374 	struct ulockfs *ulp;
3375 	struct ufs_slot slot;
3376 	timestruc_t now;
3377 	int error;
3378 	int issync;
3379 	int trans_size;
3380 	krwlock_t *first_lock;
3381 	krwlock_t *second_lock;
3382 	krwlock_t *reverse_lock;
3383 	int serr, terr;
3384 
3385 	sdp = VTOI(sdvp);
3386 	slot.fbp = NULL;
3387 	ufsvfsp = sdp->i_ufsvfs;
3388 
3389 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
3390 		tdvp = realvp;
3391 
3392 	terr = ufs_eventlookup(tdvp, tnm, cr, &tvp);
3393 	serr = ufs_eventlookup(sdvp, snm, cr, &svp);
3394 
3395 	if ((serr == 0) && ((terr == 0) || (terr == ENOENT))) {
3396 		if (tvp != NULL)
3397 			vnevent_rename_dest(tvp, tdvp, tnm, ct);
3398 
3399 		/*
3400 		 * Notify the target directory of the rename event
3401 		 * if source and target directories are not the same.
3402 		 */
3403 		if (sdvp != tdvp)
3404 			vnevent_rename_dest_dir(tdvp, ct);
3405 
3406 		if (svp != NULL)
3407 			vnevent_rename_src(svp, sdvp, snm, ct);
3408 	}
3409 
3410 	if (tvp != NULL)
3411 		VN_RELE(tvp);
3412 
3413 	if (svp != NULL)
3414 		VN_RELE(svp);
3415 
3416 retry_rename:
3417 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_RENAME_MASK);
3418 	if (error)
3419 		goto out;
3420 
3421 	if (ulp)
3422 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_RENAME,
3423 		    trans_size = (int)TOP_RENAME_SIZE(sdp));
3424 
3425 	if (VOP_REALVP(tdvp, &realvp, ct) == 0)
3426 		tdvp = realvp;
3427 
3428 	tdp = VTOI(tdvp);
3429 
3430 	/*
3431 	 * We only allow renaming of attributes from ATTRDIR to ATTRDIR.
3432 	 */
3433 	if ((tdp->i_mode & IFMT) != (sdp->i_mode & IFMT)) {
3434 		error = EINVAL;
3435 		goto unlock;
3436 	}
3437 
3438 	/*
3439 	 * Check accessibility of directory.
3440 	 */
3441 	if (error = ufs_diraccess(sdp, IEXEC, cr))
3442 		goto unlock;
3443 
3444 	/*
3445 	 * Look up inode of file we're supposed to rename.
3446 	 */
3447 	gethrestime(&now);
3448 	if (error = ufs_dirlook(sdp, snm, &sip, cr, 0, 0)) {
3449 		if (error == EAGAIN) {
3450 			if (ulp) {
3451 				TRANS_END_CSYNC(ufsvfsp, error, issync,
3452 				    TOP_RENAME, trans_size);
3453 				ufs_lockfs_end(ulp);
3454 			}
3455 			goto retry_rename;
3456 		}
3457 
3458 		goto unlock;
3459 	}
3460 
3461 	/*
3462 	 * Lock both the source and target directories (they may be
3463 	 * the same) to provide the atomicity semantics that was
3464 	 * previously provided by the per file system vfs_rename_lock
3465 	 *
3466 	 * with vfs_rename_lock removed to allow simultaneous renames
3467 	 * within a file system, ufs_dircheckpath can deadlock while
3468 	 * traversing back to ensure that source is not a parent directory
3469 	 * of target parent directory. This is because we get into
3470 	 * ufs_dircheckpath with the sdp and tdp locks held as RW_WRITER.
3471 	 * If the tdp and sdp of the simultaneous renames happen to be
3472 	 * in the path of each other, it can lead to a deadlock. This
3473 	 * can be avoided by getting the locks as RW_READER here and then
3474 	 * upgrading to RW_WRITER after completing the ufs_dircheckpath.
3475 	 *
3476 	 * We hold the target directory's i_rwlock after calling
3477 	 * ufs_lockfs_begin but in many other operations (like ufs_readdir)
3478 	 * VOP_RWLOCK is explicitly called by the filesystem independent code
3479 	 * before calling the file system operation. In these cases the order
3480 	 * is reversed (i.e i_rwlock is taken first and then ufs_lockfs_begin
3481 	 * is called). This is fine as long as ufs_lockfs_begin acts as a VOP
3482 	 * counter but with ufs_quiesce setting the SLOCK bit this becomes a
3483 	 * synchronizing object which might lead to a deadlock. So we use
3484 	 * rw_tryenter instead of rw_enter. If we fail to get this lock and
3485 	 * find that SLOCK bit is set, we call ufs_lockfs_end and restart the
3486 	 * operation.
3487 	 */
3488 retry:
3489 	first_lock = &tdp->i_rwlock;
3490 	second_lock = &sdp->i_rwlock;
3491 retry_firstlock:
3492 	if (!rw_tryenter(first_lock, RW_READER)) {
3493 		/*
3494 		 * We didn't get the lock. Check if the SLOCK is set in the
3495 		 * ufsvfs. If yes, we might be in a deadlock. Safer to give up
3496 		 * and wait for SLOCK to be cleared.
3497 		 */
3498 
3499 		if (ulp && ULOCKFS_IS_SLOCK(ulp)) {
3500 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME,
3501 			    trans_size);
3502 			ufs_lockfs_end(ulp);
3503 			goto retry_rename;
3504 
3505 		} else {
3506 			/*
3507 			 * SLOCK isn't set so this is a genuine synchronization
3508 			 * case. Let's try again after giving them a breather.
3509 			 */
3510 			delay(RETRY_LOCK_DELAY);
3511 			goto  retry_firstlock;
3512 		}
3513 	}
3514 	/*
3515 	 * Need to check if the tdp and sdp are same !!!
3516 	 */
3517 	if ((tdp != sdp) && (!rw_tryenter(second_lock, RW_READER))) {
3518 		/*
3519 		 * We didn't get the lock. Check if the SLOCK is set in the
3520 		 * ufsvfs. If yes, we might be in a deadlock. Safer to give up
3521 		 * and wait for SLOCK to be cleared.
3522 		 */
3523 
3524 		rw_exit(first_lock);
3525 		if (ulp && ULOCKFS_IS_SLOCK(ulp)) {
3526 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME,
3527 			    trans_size);
3528 			ufs_lockfs_end(ulp);
3529 			goto retry_rename;
3530 
3531 		} else {
3532 			/*
3533 			 * So we couldn't get the second level peer lock *and*
3534 			 * the SLOCK bit isn't set. Too bad we can be
3535 			 * contentding with someone wanting these locks otherway
3536 			 * round. Reverse the locks in case there is a heavy
3537 			 * contention for the second level lock.
3538 			 */
3539 			reverse_lock = first_lock;
3540 			first_lock = second_lock;
3541 			second_lock = reverse_lock;
3542 			ufs_rename_retry_cnt++;
3543 			goto  retry_firstlock;
3544 		}
3545 	}
3546 
3547 	if (sip == tdp) {
3548 		error = EINVAL;
3549 		goto errout;
3550 	}
3551 	/*
3552 	 * Make sure we can delete the source entry.  This requires
3553 	 * write permission on the containing directory.
3554 	 * Check for sticky directories.
3555 	 */
3556 	rw_enter(&sdp->i_contents, RW_READER);
3557 	rw_enter(&sip->i_contents, RW_READER);
3558 	if ((error = ufs_iaccess(sdp, IWRITE, cr, 0)) != 0 ||
3559 	    (error = ufs_sticky_remove_access(sdp, sip, cr)) != 0) {
3560 		rw_exit(&sip->i_contents);
3561 		rw_exit(&sdp->i_contents);
3562 		goto errout;
3563 	}
3564 
3565 	/*
3566 	 * If this is a rename of a directory and the parent is
3567 	 * different (".." must be changed), then the source
3568 	 * directory must not be in the directory hierarchy
3569 	 * above the target, as this would orphan everything
3570 	 * below the source directory.  Also the user must have
3571 	 * write permission in the source so as to be able to
3572 	 * change "..".
3573 	 */
3574 	if ((((sip->i_mode & IFMT) == IFDIR) ||
3575 	    ((sip->i_mode & IFMT) == IFATTRDIR)) && sdp != tdp) {
3576 		ino_t	inum;
3577 
3578 		if (error = ufs_iaccess(sip, IWRITE, cr, 0)) {
3579 			rw_exit(&sip->i_contents);
3580 			rw_exit(&sdp->i_contents);
3581 			goto errout;
3582 		}
3583 		inum = sip->i_number;
3584 		rw_exit(&sip->i_contents);
3585 		rw_exit(&sdp->i_contents);
3586 		if ((error = ufs_dircheckpath(inum, tdp, sdp, cr))) {
3587 			/*
3588 			 * If we got EAGAIN ufs_dircheckpath detected a
3589 			 * potential deadlock and backed out. We need
3590 			 * to retry the operation since sdp and tdp have
3591 			 * to be released to avoid the deadlock.
3592 			 */
3593 			if (error == EAGAIN) {
3594 				rw_exit(&tdp->i_rwlock);
3595 				if (tdp != sdp)
3596 					rw_exit(&sdp->i_rwlock);
3597 				delay(ufs_rename_backoff_delay);
3598 				ufs_rename_dircheck_retry_cnt++;
3599 				goto retry;
3600 			}
3601 			goto errout;
3602 		}
3603 	} else {
3604 		rw_exit(&sip->i_contents);
3605 		rw_exit(&sdp->i_contents);
3606 	}
3607 
3608 
3609 	/*
3610 	 * Check for renaming '.' or '..' or alias of '.'
3611 	 */
3612 	if (strcmp(snm, ".") == 0 || strcmp(snm, "..") == 0 || sdp == sip) {
3613 		error = EINVAL;
3614 		goto errout;
3615 	}
3616 
3617 	/*
3618 	 * Simultaneous renames can deadlock in ufs_dircheckpath since it
3619 	 * tries to traverse back the file tree with both tdp and sdp held
3620 	 * as RW_WRITER. To avoid that we have to hold the tdp and sdp locks
3621 	 * as RW_READERS  till ufs_dircheckpath is done.
3622 	 * Now that ufs_dircheckpath is done with, we can upgrade the locks
3623 	 * to RW_WRITER.
3624 	 */
3625 	if (!rw_tryupgrade(&tdp->i_rwlock)) {
3626 		/*
3627 		 * The upgrade failed. We got to give away the lock
3628 		 * as to avoid deadlocking with someone else who is
3629 		 * waiting for writer lock. With the lock gone, we
3630 		 * cannot be sure the checks done above will hold
3631 		 * good when we eventually get them back as writer.
3632 		 * So if we can't upgrade we drop the locks and retry
3633 		 * everything again.
3634 		 */
3635 		rw_exit(&tdp->i_rwlock);
3636 		if (tdp != sdp)
3637 			rw_exit(&sdp->i_rwlock);
3638 		delay(ufs_rename_backoff_delay);
3639 		ufs_rename_upgrade_retry_cnt++;
3640 		goto retry;
3641 	}
3642 	if (tdp != sdp) {
3643 		if (!rw_tryupgrade(&sdp->i_rwlock)) {
3644 			/*
3645 			 * The upgrade failed. We got to give away the lock
3646 			 * as to avoid deadlocking with someone else who is
3647 			 * waiting for writer lock. With the lock gone, we
3648 			 * cannot be sure the checks done above will hold
3649 			 * good when we eventually get them back as writer.
3650 			 * So if we can't upgrade we drop the locks and retry
3651 			 * everything again.
3652 			 */
3653 			rw_exit(&tdp->i_rwlock);
3654 			rw_exit(&sdp->i_rwlock);
3655 			delay(ufs_rename_backoff_delay);
3656 			ufs_rename_upgrade_retry_cnt++;
3657 			goto retry;
3658 		}
3659 	}
3660 
3661 	/*
3662 	 * Now that all the locks are held check to make sure another thread
3663 	 * didn't slip in and take out the sip.
3664 	 */
3665 	slot.status = NONE;
3666 	if ((sip->i_ctime.tv_usec * 1000) > now.tv_nsec ||
3667 	    sip->i_ctime.tv_sec > now.tv_sec) {
3668 		rw_enter(&sdp->i_ufsvfs->vfs_dqrwlock, RW_READER);
3669 		rw_enter(&sdp->i_contents, RW_WRITER);
3670 		error = ufs_dircheckforname(sdp, snm, strlen(snm), &slot,
3671 		    &ip, cr, 0);
3672 		rw_exit(&sdp->i_contents);
3673 		rw_exit(&sdp->i_ufsvfs->vfs_dqrwlock);
3674 		if (error) {
3675 			goto errout;
3676 		}
3677 		if (ip == NULL) {
3678 			error = ENOENT;
3679 			goto errout;
3680 		} else {
3681 			/*
3682 			 * If the inode was found need to drop the v_count
3683 			 * so as not to keep the filesystem from being
3684 			 * unmounted at a later time.
3685 			 */
3686 			VN_RELE(ITOV(ip));
3687 		}
3688 
3689 		/*
3690 		 * Release the slot.fbp that has the page mapped and
3691 		 * locked SE_SHARED, and could be used in in
3692 		 * ufs_direnter_lr() which needs to get the SE_EXCL lock
3693 		 * on said page.
3694 		 */
3695 		if (slot.fbp) {
3696 			fbrelse(slot.fbp, S_OTHER);
3697 			slot.fbp = NULL;
3698 		}
3699 	}
3700 
3701 	/*
3702 	 * Link source to the target.
3703 	 */
3704 	if (error = ufs_direnter_lr(tdp, tnm, DE_RENAME, sdp, sip, cr)) {
3705 		/*
3706 		 * ESAME isn't really an error; it indicates that the
3707 		 * operation should not be done because the source and target
3708 		 * are the same file, but that no error should be reported.
3709 		 */
3710 		if (error == ESAME)
3711 			error = 0;
3712 		goto errout;
3713 	}
3714 
3715 	/*
3716 	 * Unlink the source.
3717 	 * Remove the source entry.  ufs_dirremove() checks that the entry
3718 	 * still reflects sip, and returns an error if it doesn't.
3719 	 * If the entry has changed just forget about it.  Release
3720 	 * the source inode.
3721 	 */
3722 	if ((error = ufs_dirremove(sdp, snm, sip, (struct vnode *)0,
3723 	    DR_RENAME, cr)) == ENOENT)
3724 		error = 0;
3725 
3726 errout:
3727 	if (slot.fbp)
3728 		fbrelse(slot.fbp, S_OTHER);
3729 
3730 	rw_exit(&tdp->i_rwlock);
3731 	if (sdp != tdp) {
3732 		rw_exit(&sdp->i_rwlock);
3733 	}
3734 
3735 	VN_RELE(ITOV(sip));
3736 
3737 unlock:
3738 	if (ulp) {
3739 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RENAME, trans_size);
3740 		ufs_lockfs_end(ulp);
3741 	}
3742 
3743 out:
3744 	return (error);
3745 }
3746 
3747 /*ARGSUSED*/
3748 static int
ufs_mkdir(struct vnode * dvp,char * dirname,struct vattr * vap,struct vnode ** vpp,struct cred * cr,caller_context_t * ct,int flags,vsecattr_t * vsecp)3749 ufs_mkdir(struct vnode *dvp, char *dirname, struct vattr *vap,
3750 	struct vnode **vpp, struct cred *cr, caller_context_t *ct, int flags,
3751 	vsecattr_t *vsecp)
3752 {
3753 	struct inode *ip;
3754 	struct inode *xip;
3755 	struct ufsvfs *ufsvfsp;
3756 	struct ulockfs *ulp;
3757 	int error;
3758 	int issync;
3759 	int trans_size;
3760 	int indeadlock;
3761 	int retry = 1;
3762 
3763 	ASSERT((vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));
3764 
3765 	/*
3766 	 * Can't make directory in attr hidden dir
3767 	 */
3768 	if ((VTOI(dvp)->i_mode & IFMT) == IFATTRDIR)
3769 		return (EINVAL);
3770 
3771 again:
3772 	ip = VTOI(dvp);
3773 	ufsvfsp = ip->i_ufsvfs;
3774 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_MKDIR_MASK);
3775 	if (error)
3776 		goto out;
3777 	if (ulp)
3778 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_MKDIR,
3779 		    trans_size = (int)TOP_MKDIR_SIZE(ip));
3780 
3781 	/*
3782 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3783 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3784 	 * possible, retries the operation.
3785 	 */
3786 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_MKDIR, retry);
3787 	if (indeadlock)
3788 		goto again;
3789 
3790 	error = ufs_direnter_cm(ip, dirname, DE_MKDIR, vap, &xip, cr,
3791 	    (retry ? IQUIET : 0));
3792 	if (error == EAGAIN) {
3793 		if (ulp) {
3794 			TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_MKDIR,
3795 			    trans_size);
3796 			ufs_lockfs_end(ulp);
3797 		}
3798 		goto again;
3799 	}
3800 
3801 	rw_exit(&ip->i_rwlock);
3802 	if (error == 0) {
3803 		ip = xip;
3804 		*vpp = ITOV(ip);
3805 	} else if (error == EEXIST)
3806 		VN_RELE(ITOV(xip));
3807 
3808 	if (ulp) {
3809 		int terr = 0;
3810 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_MKDIR, trans_size);
3811 		ufs_lockfs_end(ulp);
3812 		if (error == 0)
3813 			error = terr;
3814 	}
3815 out:
3816 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
3817 		ufs_delete_drain_wait(ufsvfsp, 1);
3818 		retry = 0;
3819 		goto again;
3820 	}
3821 
3822 	return (error);
3823 }
3824 
3825 /*ARGSUSED*/
3826 static int
ufs_rmdir(struct vnode * vp,char * nm,struct vnode * cdir,struct cred * cr,caller_context_t * ct,int flags)3827 ufs_rmdir(struct vnode *vp, char *nm, struct vnode *cdir, struct cred *cr,
3828 	caller_context_t *ct, int flags)
3829 {
3830 	struct inode *ip = VTOI(vp);
3831 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
3832 	struct ulockfs *ulp;
3833 	vnode_t *rmvp = NULL;	/* Vnode of removed directory */
3834 	int error;
3835 	int issync;
3836 	int trans_size;
3837 	int indeadlock;
3838 
3839 	/*
3840 	 * don't let the delete queue get too long
3841 	 */
3842 	if (ufsvfsp == NULL) {
3843 		error = EIO;
3844 		goto out;
3845 	}
3846 	if (ufsvfsp->vfs_delete.uq_ne > ufs_idle_max)
3847 		ufs_delete_drain(vp->v_vfsp, 1, 1);
3848 
3849 	error = ufs_eventlookup(vp, nm, cr, &rmvp);
3850 	if (rmvp != NULL) {
3851 		/* Only send the event if there were no errors */
3852 		if (error == 0)
3853 			vnevent_rmdir(rmvp, vp, nm, ct);
3854 		VN_RELE(rmvp);
3855 	}
3856 
3857 retry_rmdir:
3858 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_RMDIR_MASK);
3859 	if (error)
3860 		goto out;
3861 
3862 	if (ulp)
3863 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_RMDIR,
3864 		    trans_size = TOP_RMDIR_SIZE);
3865 
3866 	/*
3867 	 * ufs_tryirwlock_trans uses rw_tryenter and checks for SLOCK
3868 	 * to avoid i_rwlock, ufs_lockfs_begin deadlock. If deadlock
3869 	 * possible, retries the operation.
3870 	 */
3871 	ufs_tryirwlock_trans(&ip->i_rwlock, RW_WRITER, TOP_RMDIR, retry);
3872 	if (indeadlock)
3873 		goto retry_rmdir;
3874 	error = ufs_dirremove(ip, nm, (struct inode *)0, cdir, DR_RMDIR, cr);
3875 
3876 	rw_exit(&ip->i_rwlock);
3877 
3878 	if (ulp) {
3879 		TRANS_END_CSYNC(ufsvfsp, error, issync, TOP_RMDIR,
3880 		    trans_size);
3881 		ufs_lockfs_end(ulp);
3882 	}
3883 
3884 out:
3885 	return (error);
3886 }
3887 
3888 /* ARGSUSED */
3889 static int
ufs_readdir(struct vnode * vp,struct uio * uiop,struct cred * cr,int * eofp,caller_context_t * ct,int flags)3890 ufs_readdir(
3891 	struct vnode *vp,
3892 	struct uio *uiop,
3893 	struct cred *cr,
3894 	int *eofp,
3895 	caller_context_t *ct,
3896 	int flags)
3897 {
3898 	struct iovec *iovp;
3899 	struct inode *ip;
3900 	struct direct *idp;
3901 	struct dirent64 *odp;
3902 	struct fbuf *fbp;
3903 	struct ufsvfs *ufsvfsp;
3904 	struct ulockfs *ulp;
3905 	caddr_t outbuf;
3906 	size_t bufsize;
3907 	uint_t offset;
3908 	uint_t bytes_wanted, total_bytes_wanted;
3909 	int incount = 0;
3910 	int outcount = 0;
3911 	int error;
3912 
3913 	ip = VTOI(vp);
3914 	ASSERT(RW_READ_HELD(&ip->i_rwlock));
3915 
3916 	if (uiop->uio_loffset >= MAXOFF32_T) {
3917 		if (eofp)
3918 			*eofp = 1;
3919 		return (0);
3920 	}
3921 
3922 	/*
3923 	 * Check if we have been called with a valid iov_len
3924 	 * and bail out if not, otherwise we may potentially loop
3925 	 * forever further down.
3926 	 */
3927 	if (uiop->uio_iov->iov_len <= 0) {
3928 		error = EINVAL;
3929 		goto out;
3930 	}
3931 
3932 	/*
3933 	 * Large Files: When we come here we are guaranteed that
3934 	 * uio_offset can be used safely. The high word is zero.
3935 	 */
3936 
3937 	ufsvfsp = ip->i_ufsvfs;
3938 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_READDIR_MASK);
3939 	if (error)
3940 		goto out;
3941 
3942 	iovp = uiop->uio_iov;
3943 	total_bytes_wanted = iovp->iov_len;
3944 
3945 	/* Large Files: directory files should not be "large" */
3946 
3947 	ASSERT(ip->i_size <= MAXOFF32_T);
3948 
3949 	/* Force offset to be valid (to guard against bogus lseek() values) */
3950 	offset = (uint_t)uiop->uio_offset & ~(DIRBLKSIZ - 1);
3951 
3952 	/* Quit if at end of file or link count of zero (posix) */
3953 	if (offset >= (uint_t)ip->i_size || ip->i_nlink <= 0) {
3954 		if (eofp)
3955 			*eofp = 1;
3956 		error = 0;
3957 		goto unlock;
3958 	}
3959 
3960 	/*
3961 	 * Get space to change directory entries into fs independent format.
3962 	 * Do fast alloc for the most commonly used-request size (filesystem
3963 	 * block size).
3964 	 */
3965 	if (uiop->uio_segflg != UIO_SYSSPACE || uiop->uio_iovcnt != 1) {
3966 		bufsize = total_bytes_wanted;
3967 		outbuf = kmem_alloc(bufsize, KM_SLEEP);
3968 		odp = (struct dirent64 *)outbuf;
3969 	} else {
3970 		bufsize = total_bytes_wanted;
3971 		odp = (struct dirent64 *)iovp->iov_base;
3972 	}
3973 
3974 nextblk:
3975 	bytes_wanted = total_bytes_wanted;
3976 
3977 	/* Truncate request to file size */
3978 	if (offset + bytes_wanted > (int)ip->i_size)
3979 		bytes_wanted = (int)(ip->i_size - offset);
3980 
3981 	/* Comply with MAXBSIZE boundary restrictions of fbread() */
3982 	if ((offset & MAXBOFFSET) + bytes_wanted > MAXBSIZE)
3983 		bytes_wanted = MAXBSIZE - (offset & MAXBOFFSET);
3984 
3985 	/*
3986 	 * Read in the next chunk.
3987 	 * We are still holding the i_rwlock.
3988 	 */
3989 	error = fbread(vp, (offset_t)offset, bytes_wanted, S_OTHER, &fbp);
3990 
3991 	if (error)
3992 		goto update_inode;
3993 	if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) && (ip->i_fs->fs_ronly == 0) &&
3994 	    (!ufsvfsp->vfs_noatime)) {
3995 		ip->i_flag |= IACC;
3996 	}
3997 	incount = 0;
3998 	idp = (struct direct *)fbp->fb_addr;
3999 	if (idp->d_ino == 0 && idp->d_reclen == 0 && idp->d_namlen == 0) {
4000 		cmn_err(CE_WARN, "ufs_readdir: bad dir, inumber = %llu, "
4001 		    "fs = %s\n",
4002 		    (u_longlong_t)ip->i_number, ufsvfsp->vfs_fs->fs_fsmnt);
4003 		fbrelse(fbp, S_OTHER);
4004 		error = ENXIO;
4005 		goto update_inode;
4006 	}
4007 	/* Transform to file-system independent format */
4008 	while (incount < bytes_wanted) {
4009 		/*
4010 		 * If the current directory entry is mangled, then skip
4011 		 * to the next block.  It would be nice to set the FSBAD
4012 		 * flag in the super-block so that a fsck is forced on
4013 		 * next reboot, but locking is a problem.
4014 		 */
4015 		if (idp->d_reclen & 0x3) {
4016 			offset = (offset + DIRBLKSIZ) & ~(DIRBLKSIZ-1);
4017 			break;
4018 		}
4019 
4020 		/* Skip to requested offset and skip empty entries */
4021 		if (idp->d_ino != 0 && offset >= (uint_t)uiop->uio_offset) {
4022 			ushort_t this_reclen =
4023 			    DIRENT64_RECLEN(idp->d_namlen);
4024 			/* Buffer too small for any entries */
4025 			if (!outcount && this_reclen > bufsize) {
4026 				fbrelse(fbp, S_OTHER);
4027 				error = EINVAL;
4028 				goto update_inode;
4029 			}
4030 			/* If would overrun the buffer, quit */
4031 			if (outcount + this_reclen > bufsize) {
4032 				break;
4033 			}
4034 			/* Take this entry */
4035 			odp->d_ino = (ino64_t)idp->d_ino;
4036 			odp->d_reclen = (ushort_t)this_reclen;
4037 			odp->d_off = (offset_t)(offset + idp->d_reclen);
4038 
4039 			/* use strncpy(9f) to zero out uninitialized bytes */
4040 
4041 			ASSERT(strlen(idp->d_name) + 1 <=
4042 			    DIRENT64_NAMELEN(this_reclen));
4043 			(void) strncpy(odp->d_name, idp->d_name,
4044 			    DIRENT64_NAMELEN(this_reclen));
4045 			outcount += odp->d_reclen;
4046 			odp = (struct dirent64 *)
4047 			    ((intptr_t)odp + odp->d_reclen);
4048 			ASSERT(outcount <= bufsize);
4049 		}
4050 		if (idp->d_reclen) {
4051 			incount += idp->d_reclen;
4052 			offset += idp->d_reclen;
4053 			idp = (struct direct *)((intptr_t)idp + idp->d_reclen);
4054 		} else {
4055 			offset = (offset + DIRBLKSIZ) & ~(DIRBLKSIZ-1);
4056 			break;
4057 		}
4058 	}
4059 	/* Release the chunk */
4060 	fbrelse(fbp, S_OTHER);
4061 
4062 	/* Read whole block, but got no entries, read another if not eof */
4063 
4064 	/*
4065 	 * Large Files: casting i_size to int here is not a problem
4066 	 * because directory sizes are always less than MAXOFF32_T.
4067 	 * See assertion above.
4068 	 */
4069 
4070 	if (offset < (int)ip->i_size && !outcount)
4071 		goto nextblk;
4072 
4073 	/* Copy out the entry data */
4074 	if (uiop->uio_segflg == UIO_SYSSPACE && uiop->uio_iovcnt == 1) {
4075 		iovp->iov_base += outcount;
4076 		iovp->iov_len -= outcount;
4077 		uiop->uio_resid -= outcount;
4078 		uiop->uio_offset = offset;
4079 	} else if ((error = uiomove(outbuf, (long)outcount, UIO_READ,
4080 	    uiop)) == 0)
4081 		uiop->uio_offset = offset;
4082 update_inode:
4083 	ITIMES(ip);
4084 	if (uiop->uio_segflg != UIO_SYSSPACE || uiop->uio_iovcnt != 1)
4085 		kmem_free(outbuf, bufsize);
4086 
4087 	if (eofp && error == 0)
4088 		*eofp = (uiop->uio_offset >= (int)ip->i_size);
4089 unlock:
4090 	if (ulp) {
4091 		ufs_lockfs_end(ulp);
4092 	}
4093 out:
4094 	return (error);
4095 }
4096 
4097 /*ARGSUSED*/
4098 static int
ufs_symlink(struct vnode * dvp,char * linkname,struct vattr * vap,char * target,struct cred * cr,caller_context_t * ct,int flags)4099 ufs_symlink(
4100 	struct vnode *dvp,		/* ptr to parent dir vnode */
4101 	char *linkname,			/* name of symbolic link */
4102 	struct vattr *vap,		/* attributes */
4103 	char *target,			/* target path */
4104 	struct cred *cr,		/* user credentials */
4105 	caller_context_t *ct,
4106 	int flags)
4107 {
4108 	struct inode *ip, *dip = VTOI(dvp);
4109 	struct ufsvfs *ufsvfsp = dip->i_ufsvfs;
4110 	struct ulockfs *ulp;
4111 	int error;
4112 	int issync;
4113 	int trans_size;
4114 	int residual;
4115 	int ioflag;
4116 	int retry = 1;
4117 
4118 	/*
4119 	 * No symlinks in attrdirs at this time
4120 	 */
4121 	if ((VTOI(dvp)->i_mode & IFMT) == IFATTRDIR)
4122 		return (EINVAL);
4123 
4124 again:
4125 	ip = (struct inode *)NULL;
4126 	vap->va_type = VLNK;
4127 	vap->va_rdev = 0;
4128 
4129 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SYMLINK_MASK);
4130 	if (error)
4131 		goto out;
4132 
4133 	if (ulp)
4134 		TRANS_BEGIN_CSYNC(ufsvfsp, issync, TOP_SYMLINK,
4135 		    trans_size = (int)TOP_SYMLINK_SIZE(dip));
4136 
4137 	/*
4138 	 * We must create the inode before the directory entry, to avoid
4139 	 * racing with readlink().  ufs_dirmakeinode requires that we
4140 	 * hold the quota lock as reader, and directory locks as writer.
4141 	 */
4142 
4143 	rw_enter(&dip->i_rwlock, RW_WRITER);
4144 	rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4145 	rw_enter(&dip->i_contents, RW_WRITER);
4146 
4147 	/*
4148 	 * Suppress any out of inodes messages if we will retry on
4149 	 * ENOSP
4150 	 */
4151 	if (retry)
4152 		dip->i_flag |= IQUIET;
4153 
4154 	error = ufs_dirmakeinode(dip, &ip, vap, DE_SYMLINK, cr);
4155 
4156 	dip->i_flag &= ~IQUIET;
4157 
4158 	rw_exit(&dip->i_contents);
4159 	rw_exit(&ufsvfsp->vfs_dqrwlock);
4160 	rw_exit(&dip->i_rwlock);
4161 
4162 	if (error)
4163 		goto unlock;
4164 
4165 	/*
4166 	 * OK.  The inode has been created.  Write out the data of the
4167 	 * symbolic link.  Since symbolic links are metadata, and should
4168 	 * remain consistent across a system crash, we need to force the
4169 	 * data out synchronously.
4170 	 *
4171 	 * (This is a change from the semantics in earlier releases, which
4172 	 * only created symbolic links synchronously if the semi-documented
4173 	 * 'syncdir' option was set, or if we were being invoked by the NFS
4174 	 * server, which requires symbolic links to be created synchronously.)
4175 	 *
4176 	 * We need to pass in a pointer for the residual length; otherwise
4177 	 * ufs_rdwri() will always return EIO if it can't write the data,
4178 	 * even if the error was really ENOSPC or EDQUOT.
4179 	 */
4180 
4181 	ioflag = FWRITE | FDSYNC;
4182 	residual = 0;
4183 
4184 	rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4185 	rw_enter(&ip->i_contents, RW_WRITER);
4186 
4187 	/*
4188 	 * Suppress file system full messages if we will retry
4189 	 */
4190 	if (retry)
4191 		ip->i_flag |= IQUIET;
4192 
4193 	error = ufs_rdwri(UIO_WRITE, ioflag, ip, target, strlen(target),
4194 	    (offset_t)0, UIO_SYSSPACE, &residual, cr);
4195 
4196 	ip->i_flag &= ~IQUIET;
4197 
4198 	if (error) {
4199 		rw_exit(&ip->i_contents);
4200 		rw_exit(&ufsvfsp->vfs_dqrwlock);
4201 		goto remove;
4202 	}
4203 
4204 	/*
4205 	 * If the link's data is small enough, we can cache it in the inode.
4206 	 * This is a "fast symbolic link".  We don't use the first direct
4207 	 * block because that's actually used to point at the symbolic link's
4208 	 * contents on disk; but we know that none of the other direct or
4209 	 * indirect blocks can be used because symbolic links are restricted
4210 	 * to be smaller than a file system block.
4211 	 */
4212 
4213 	ASSERT(MAXPATHLEN <= VBSIZE(ITOV(ip)));
4214 
4215 	if (ip->i_size > 0 && ip->i_size <= FSL_SIZE) {
4216 		if (kcopy(target, &ip->i_db[1], ip->i_size) == 0) {
4217 			ip->i_flag |= IFASTSYMLNK;
4218 		} else {
4219 			int i;
4220 			/* error, clear garbage left behind */
4221 			for (i = 1; i < NDADDR; i++)
4222 				ip->i_db[i] = 0;
4223 			for (i = 0; i < NIADDR; i++)
4224 				ip->i_ib[i] = 0;
4225 		}
4226 	}
4227 
4228 	rw_exit(&ip->i_contents);
4229 	rw_exit(&ufsvfsp->vfs_dqrwlock);
4230 
4231 	/*
4232 	 * OK.  We've successfully created the symbolic link.  All that
4233 	 * remains is to insert it into the appropriate directory.
4234 	 */
4235 
4236 	rw_enter(&dip->i_rwlock, RW_WRITER);
4237 	error = ufs_direnter_lr(dip, linkname, DE_SYMLINK, NULL, ip, cr);
4238 	rw_exit(&dip->i_rwlock);
4239 
4240 	/*
4241 	 * Fall through into remove-on-error code.  We're either done, or we
4242 	 * need to remove the inode (if we couldn't insert it).
4243 	 */
4244 
4245 remove:
4246 	if (error && (ip != NULL)) {
4247 		rw_enter(&ip->i_contents, RW_WRITER);
4248 		ip->i_nlink--;
4249 		ip->i_flag |= ICHG;
4250 		ip->i_seq++;
4251 		ufs_setreclaim(ip);
4252 		rw_exit(&ip->i_contents);
4253 	}
4254 
4255 unlock:
4256 	if (ip != NULL)
4257 		VN_RELE(ITOV(ip));
4258 
4259 	if (ulp) {
4260 		int terr = 0;
4261 
4262 		TRANS_END_CSYNC(ufsvfsp, terr, issync, TOP_SYMLINK,
4263 		    trans_size);
4264 		ufs_lockfs_end(ulp);
4265 		if (error == 0)
4266 			error = terr;
4267 	}
4268 
4269 	/*
4270 	 * We may have failed due to lack of an inode or of a block to
4271 	 * store the target in.  Try flushing the delete queue to free
4272 	 * logically-available things up and try again.
4273 	 */
4274 	if ((error == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
4275 		ufs_delete_drain_wait(ufsvfsp, 1);
4276 		retry = 0;
4277 		goto again;
4278 	}
4279 
4280 out:
4281 	return (error);
4282 }
4283 
4284 /*
4285  * Ufs specific routine used to do ufs io.
4286  */
4287 int
ufs_rdwri(enum uio_rw rw,int ioflag,struct inode * ip,caddr_t base,ssize_t len,offset_t offset,enum uio_seg seg,int * aresid,struct cred * cr)4288 ufs_rdwri(enum uio_rw rw, int ioflag, struct inode *ip, caddr_t base,
4289 	ssize_t len, offset_t offset, enum uio_seg seg, int *aresid,
4290 	struct cred *cr)
4291 {
4292 	struct uio auio;
4293 	struct iovec aiov;
4294 	int error;
4295 
4296 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
4297 
4298 	bzero((caddr_t)&auio, sizeof (uio_t));
4299 	bzero((caddr_t)&aiov, sizeof (iovec_t));
4300 
4301 	aiov.iov_base = base;
4302 	aiov.iov_len = len;
4303 	auio.uio_iov = &aiov;
4304 	auio.uio_iovcnt = 1;
4305 	auio.uio_loffset = offset;
4306 	auio.uio_segflg = (short)seg;
4307 	auio.uio_resid = len;
4308 
4309 	if (rw == UIO_WRITE) {
4310 		auio.uio_fmode = FWRITE;
4311 		auio.uio_extflg = UIO_COPY_DEFAULT;
4312 		auio.uio_llimit = curproc->p_fsz_ctl;
4313 		error = wrip(ip, &auio, ioflag, cr);
4314 	} else {
4315 		auio.uio_fmode = FREAD;
4316 		auio.uio_extflg = UIO_COPY_CACHED;
4317 		auio.uio_llimit = MAXOFFSET_T;
4318 		error = rdip(ip, &auio, ioflag, cr);
4319 	}
4320 
4321 	if (aresid) {
4322 		*aresid = auio.uio_resid;
4323 	} else if (auio.uio_resid) {
4324 		error = EIO;
4325 	}
4326 	return (error);
4327 }
4328 
4329 /*ARGSUSED*/
4330 static int
ufs_fid(struct vnode * vp,struct fid * fidp,caller_context_t * ct)4331 ufs_fid(struct vnode *vp, struct fid *fidp, caller_context_t *ct)
4332 {
4333 	struct ufid *ufid;
4334 	struct inode *ip = VTOI(vp);
4335 
4336 	if (ip->i_ufsvfs == NULL)
4337 		return (EIO);
4338 
4339 	if (fidp->fid_len < (sizeof (struct ufid) - sizeof (ushort_t))) {
4340 		fidp->fid_len = sizeof (struct ufid) - sizeof (ushort_t);
4341 		return (ENOSPC);
4342 	}
4343 
4344 	ufid = (struct ufid *)fidp;
4345 	bzero((char *)ufid, sizeof (struct ufid));
4346 	ufid->ufid_len = sizeof (struct ufid) - sizeof (ushort_t);
4347 	ufid->ufid_ino = ip->i_number;
4348 	ufid->ufid_gen = ip->i_gen;
4349 
4350 	return (0);
4351 }
4352 
4353 /* ARGSUSED2 */
4354 static int
ufs_rwlock(struct vnode * vp,int write_lock,caller_context_t * ctp)4355 ufs_rwlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
4356 {
4357 	struct inode	*ip = VTOI(vp);
4358 	struct ufsvfs	*ufsvfsp;
4359 	int		forcedirectio;
4360 
4361 	/*
4362 	 * Read case is easy.
4363 	 */
4364 	if (!write_lock) {
4365 		rw_enter(&ip->i_rwlock, RW_READER);
4366 		return (V_WRITELOCK_FALSE);
4367 	}
4368 
4369 	/*
4370 	 * Caller has requested a writer lock, but that inhibits any
4371 	 * concurrency in the VOPs that follow. Acquire the lock shared
4372 	 * and defer exclusive access until it is known to be needed in
4373 	 * other VOP handlers. Some cases can be determined here.
4374 	 */
4375 
4376 	/*
4377 	 * If directio is not set, there is no chance of concurrency,
4378 	 * so just acquire the lock exclusive. Beware of a forced
4379 	 * unmount before looking at the mount option.
4380 	 */
4381 	ufsvfsp = ip->i_ufsvfs;
4382 	forcedirectio = ufsvfsp ? ufsvfsp->vfs_forcedirectio : 0;
4383 	if (!(ip->i_flag & IDIRECTIO || forcedirectio) ||
4384 	    !ufs_allow_shared_writes) {
4385 		rw_enter(&ip->i_rwlock, RW_WRITER);
4386 		return (V_WRITELOCK_TRUE);
4387 	}
4388 
4389 	/*
4390 	 * Mandatory locking forces acquiring i_rwlock exclusive.
4391 	 */
4392 	if (MANDLOCK(vp, ip->i_mode)) {
4393 		rw_enter(&ip->i_rwlock, RW_WRITER);
4394 		return (V_WRITELOCK_TRUE);
4395 	}
4396 
4397 	/*
4398 	 * Acquire the lock shared in case a concurrent write follows.
4399 	 * Mandatory locking could have become enabled before the lock
4400 	 * was acquired. Re-check and upgrade if needed.
4401 	 */
4402 	rw_enter(&ip->i_rwlock, RW_READER);
4403 	if (MANDLOCK(vp, ip->i_mode)) {
4404 		rw_exit(&ip->i_rwlock);
4405 		rw_enter(&ip->i_rwlock, RW_WRITER);
4406 		return (V_WRITELOCK_TRUE);
4407 	}
4408 	return (V_WRITELOCK_FALSE);
4409 }
4410 
4411 /*ARGSUSED*/
4412 static void
ufs_rwunlock(struct vnode * vp,int write_lock,caller_context_t * ctp)4413 ufs_rwunlock(struct vnode *vp, int write_lock, caller_context_t *ctp)
4414 {
4415 	struct inode	*ip = VTOI(vp);
4416 
4417 	rw_exit(&ip->i_rwlock);
4418 }
4419 
4420 /* ARGSUSED */
4421 static int
ufs_seek(struct vnode * vp,offset_t ooff,offset_t * noffp,caller_context_t * ct)4422 ufs_seek(struct vnode *vp, offset_t ooff, offset_t *noffp,
4423 	caller_context_t *ct)
4424 {
4425 	return ((*noffp < 0 || *noffp > MAXOFFSET_T) ? EINVAL : 0);
4426 }
4427 
4428 /* ARGSUSED */
4429 static int
ufs_frlock(struct vnode * vp,int cmd,struct flock64 * bfp,int flag,offset_t offset,struct flk_callback * flk_cbp,struct cred * cr,caller_context_t * ct)4430 ufs_frlock(struct vnode *vp, int cmd, struct flock64 *bfp, int flag,
4431 	offset_t offset, struct flk_callback *flk_cbp, struct cred *cr,
4432 	caller_context_t *ct)
4433 {
4434 	struct inode *ip = VTOI(vp);
4435 
4436 	if (ip->i_ufsvfs == NULL)
4437 		return (EIO);
4438 
4439 	/*
4440 	 * If file is being mapped, disallow frlock.
4441 	 * XXX I am not holding tlock while checking i_mapcnt because the
4442 	 * current locking strategy drops all locks before calling fs_frlock.
4443 	 * So, mapcnt could change before we enter fs_frlock making is
4444 	 * meaningless to have held tlock in the first place.
4445 	 */
4446 	if (ip->i_mapcnt > 0 && MANDLOCK(vp, ip->i_mode))
4447 		return (EAGAIN);
4448 	return (fs_frlock(vp, cmd, bfp, flag, offset, flk_cbp, cr, ct));
4449 }
4450 
4451 /* ARGSUSED */
4452 static int
ufs_space(struct vnode * vp,int cmd,struct flock64 * bfp,int flag,offset_t offset,cred_t * cr,caller_context_t * ct)4453 ufs_space(struct vnode *vp, int cmd, struct flock64 *bfp, int flag,
4454 	offset_t offset, cred_t *cr, caller_context_t *ct)
4455 {
4456 	struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
4457 	struct ulockfs *ulp;
4458 	int error;
4459 
4460 	if ((error = convoff(vp, bfp, 0, offset)) == 0) {
4461 		if (cmd == F_FREESP) {
4462 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
4463 			    ULOCKFS_SPACE_MASK);
4464 			if (error)
4465 				return (error);
4466 			error = ufs_freesp(vp, bfp, flag, cr);
4467 
4468 			if (error == 0 && bfp->l_start == 0)
4469 				vnevent_truncate(vp, ct);
4470 		} else if (cmd == F_ALLOCSP) {
4471 			error = ufs_lockfs_begin(ufsvfsp, &ulp,
4472 			    ULOCKFS_FALLOCATE_MASK);
4473 			if (error)
4474 				return (error);
4475 			error = ufs_allocsp(vp, bfp, cr);
4476 		} else
4477 			return (EINVAL); /* Command not handled here */
4478 
4479 		if (ulp)
4480 			ufs_lockfs_end(ulp);
4481 
4482 	}
4483 	return (error);
4484 }
4485 
4486 /*
4487  * Used to determine if read ahead should be done. Also used to
4488  * to determine when write back occurs.
4489  */
4490 #define	CLUSTSZ(ip)		((ip)->i_ufsvfs->vfs_ioclustsz)
4491 
4492 /*
4493  * A faster version of ufs_getpage.
4494  *
4495  * We optimize by inlining the pvn_getpages iterator, eliminating
4496  * calls to bmap_read if file doesn't have UFS holes, and avoiding
4497  * the overhead of page_exists().
4498  *
4499  * When files has UFS_HOLES and ufs_getpage is called with S_READ,
4500  * we set *protp to PROT_READ to avoid calling bmap_read. This approach
4501  * victimizes performance when a file with UFS holes is faulted
4502  * first in the S_READ mode, and then in the S_WRITE mode. We will get
4503  * two MMU faults in this case.
4504  *
4505  * XXX - the inode fields which control the sequential mode are not
4506  *	 protected by any mutex. The read ahead will act wild if
4507  *	 multiple processes will access the file concurrently and
4508  *	 some of them in sequential mode. One particulary bad case
4509  *	 is if another thread will change the value of i_nextrio between
4510  *	 the time this thread tests the i_nextrio value and then reads it
4511  *	 again to use it as the offset for the read ahead.
4512  */
4513 /*ARGSUSED*/
4514 static int
ufs_getpage(struct vnode * vp,offset_t off,size_t len,uint_t * protp,page_t * plarr[],size_t plsz,struct seg * seg,caddr_t addr,enum seg_rw rw,struct cred * cr,caller_context_t * ct)4515 ufs_getpage(struct vnode *vp, offset_t off, size_t len, uint_t *protp,
4516 	page_t *plarr[], size_t plsz, struct seg *seg, caddr_t addr,
4517 	enum seg_rw rw, struct cred *cr, caller_context_t *ct)
4518 {
4519 	u_offset_t	uoff = (u_offset_t)off; /* type conversion */
4520 	u_offset_t	pgoff;
4521 	u_offset_t	eoff;
4522 	struct inode 	*ip = VTOI(vp);
4523 	struct ufsvfs	*ufsvfsp = ip->i_ufsvfs;
4524 	struct fs 	*fs;
4525 	struct ulockfs	*ulp;
4526 	page_t		**pl;
4527 	caddr_t		pgaddr;
4528 	krw_t		rwtype;
4529 	int 		err;
4530 	int		has_holes;
4531 	int		beyond_eof;
4532 	int		seqmode;
4533 	int		pgsize = PAGESIZE;
4534 	int		dolock;
4535 	int		do_qlock;
4536 	int		trans_size;
4537 
4538 	ASSERT((uoff & PAGEOFFSET) == 0);
4539 
4540 	if (protp)
4541 		*protp = PROT_ALL;
4542 
4543 	/*
4544 	 * Obey the lockfs protocol
4545 	 */
4546 	err = ufs_lockfs_begin_getpage(ufsvfsp, &ulp, seg,
4547 	    rw == S_READ || rw == S_EXEC, protp);
4548 	if (err)
4549 		goto out;
4550 
4551 	fs = ufsvfsp->vfs_fs;
4552 
4553 	if (ulp && (rw == S_CREATE || rw == S_WRITE) &&
4554 	    !(vp->v_flag & VISSWAP)) {
4555 		/*
4556 		 * Try to start a transaction, will return if blocking is
4557 		 * expected to occur and the address space is not the
4558 		 * kernel address space.
4559 		 */
4560 		trans_size = TOP_GETPAGE_SIZE(ip);
4561 		if (seg->s_as != &kas) {
4562 			TRANS_TRY_BEGIN_ASYNC(ufsvfsp, TOP_GETPAGE,
4563 			    trans_size, err)
4564 			if (err == EWOULDBLOCK) {
4565 				/*
4566 				 * Use EDEADLK here because the VM code
4567 				 * can normally never see this error.
4568 				 */
4569 				err = EDEADLK;
4570 				ufs_lockfs_end(ulp);
4571 				goto out;
4572 			}
4573 		} else {
4574 			TRANS_BEGIN_ASYNC(ufsvfsp, TOP_GETPAGE, trans_size);
4575 		}
4576 	}
4577 
4578 	if (vp->v_flag & VNOMAP) {
4579 		err = ENOSYS;
4580 		goto unlock;
4581 	}
4582 
4583 	seqmode = ip->i_nextr == uoff && rw != S_CREATE;
4584 
4585 	rwtype = RW_READER;		/* start as a reader */
4586 	dolock = (rw_owner(&ip->i_contents) != curthread);
4587 	/*
4588 	 * If this thread owns the lock, i.e., this thread grabbed it
4589 	 * as writer somewhere above, then we don't need to grab the
4590 	 * lock as reader in this routine.
4591 	 */
4592 	do_qlock = (rw_owner(&ufsvfsp->vfs_dqrwlock) != curthread);
4593 
4594 retrylock:
4595 	if (dolock) {
4596 		/*
4597 		 * Grab the quota lock if we need to call
4598 		 * bmap_write() below (with i_contents as writer).
4599 		 */
4600 		if (do_qlock && rwtype == RW_WRITER)
4601 			rw_enter(&ufsvfsp->vfs_dqrwlock, RW_READER);
4602 		rw_enter(&ip->i_contents, rwtype);
4603 	}
4604 
4605 	/*
4606 	 * We may be getting called as a side effect of a bmap using
4607 	 * fbread() when the blocks might be being allocated and the
4608 	 * size has not yet been up'ed.  In this case we want to be
4609 	 * able to return zero pages if we get back UFS_HOLE from
4610 	 * calling bmap for a non write case here.  We also might have
4611 	 * to read some frags from the disk into a page if we are
4612 	 * extending the number of frags for a given lbn in bmap().
4613 	 * Large Files: The read of i_size here is atomic because
4614 	 * i_contents is held here. If dolock is zero, the lock
4615 	 * is held in bmap routines.
4616 	 */
4617 	beyond_eof = uoff + len >
4618 	    P2ROUNDUP_TYPED(ip->i_size, PAGESIZE, u_offset_t);
4619 	if (beyond_eof && seg != segkmap) {
4620 		if (dolock) {
4621 			rw_exit(&ip->i_contents);
4622 			if (do_qlock && rwtype == RW_WRITER)
4623 				rw_exit(&ufsvfsp->vfs_dqrwlock);
4624 		}
4625 		err = EFAULT;
4626 		goto unlock;
4627 	}
4628 
4629 	/*
4630 	 * Must hold i_contents lock throughout the call to pvn_getpages
4631 	 * since locked pages are returned from each call to ufs_getapage.
4632 	 * Must *not* return locked pages and then try for contents lock
4633 	 * due to lock ordering requirements (inode > page)
4634 	 */
4635 
4636 	has_holes = bmap_has_holes(ip);
4637 
4638 	if ((rw == S_WRITE || rw == S_CREATE) && has_holes && !beyond_eof) {
4639 		int	blk_size;
4640 		u_offset_t offset;
4641 
4642 		/*
4643 		 * We must acquire the RW_WRITER lock in order to
4644 		 * call bmap_write().
4645 		 */
4646 		if (dolock && rwtype == RW_READER) {
4647 			rwtype = RW_WRITER;
4648 
4649 			/*
4650 			 * Grab the quota lock before
4651 			 * upgrading i_contents, but if we can't grab it
4652 			 * don't wait here due to lock order:
4653 			 * vfs_dqrwlock > i_contents.
4654 			 */
4655 			if (do_qlock &&
4656 			    rw_tryenter(&ufsvfsp->vfs_dqrwlock, RW_READER)
4657 			    == 0) {
4658 				rw_exit(&ip->i_contents);
4659 				goto retrylock;
4660 			}
4661 			if (!rw_tryupgrade(&ip->i_contents)) {
4662 				rw_exit(&ip->i_contents);
4663 				if (do_qlock)
4664 					rw_exit(&ufsvfsp->vfs_dqrwlock);
4665 				goto retrylock;
4666 			}
4667 		}
4668 
4669 		/*
4670 		 * May be allocating disk blocks for holes here as
4671 		 * a result of mmap faults. write(2) does the bmap_write
4672 		 * in rdip/wrip, not here. We are not dealing with frags
4673 		 * in this case.
4674 		 */
4675 		/*
4676 		 * Large Files: We cast fs_bmask field to offset_t
4677 		 * just as we do for MAXBMASK because uoff is a 64-bit
4678 		 * data type. fs_bmask will still be a 32-bit type
4679 		 * as we cannot change any ondisk data structures.
4680 		 */
4681 
4682 		offset = uoff & (offset_t)fs->fs_bmask;
4683 		while (offset < uoff + len) {
4684 			blk_size = (int)blksize(fs, ip, lblkno(fs, offset));
4685 			err = bmap_write(ip, offset, blk_size,
4686 			    BI_NORMAL, NULL, cr);
4687 			if (ip->i_flag & (ICHG|IUPD))
4688 				ip->i_seq++;
4689 			if (err)
4690 				goto update_inode;
4691 			offset += blk_size; /* XXX - make this contig */
4692 		}
4693 	}
4694 
4695 	/*
4696 	 * Can be a reader from now on.
4697 	 */
4698 	if (dolock && rwtype == RW_WRITER) {
4699 		rw_downgrade(&ip->i_contents);
4700 		/*
4701 		 * We can release vfs_dqrwlock early so do it, but make
4702 		 * sure we don't try to release it again at the bottom.
4703 		 */
4704 		if (do_qlock) {
4705 			rw_exit(&ufsvfsp->vfs_dqrwlock);
4706 			do_qlock = 0;
4707 		}
4708 	}
4709 
4710 	/*
4711 	 * We remove PROT_WRITE in cases when the file has UFS holes
4712 	 * because we don't  want to call bmap_read() to check each
4713 	 * page if it is backed with a disk block.
4714 	 */
4715 	if (protp && has_holes && rw != S_WRITE && rw != S_CREATE)
4716 		*protp &= ~PROT_WRITE;
4717 
4718 	err = 0;
4719 
4720 	/*
4721 	 * The loop looks up pages in the range [off, off + len).
4722 	 * For each page, we first check if we should initiate an asynchronous
4723 	 * read ahead before we call page_lookup (we may sleep in page_lookup
4724 	 * for a previously initiated disk read).
4725 	 */
4726 	eoff = (uoff + len);
4727 	for (pgoff = uoff, pgaddr = addr, pl = plarr;
4728 	    pgoff < eoff; /* empty */) {
4729 		page_t	*pp;
4730 		u_offset_t	nextrio;
4731 		se_t	se;
4732 		int retval;
4733 
4734 		se = ((rw == S_CREATE || rw == S_OTHER) ? SE_EXCL : SE_SHARED);
4735 
4736 		/* Handle async getpage (faultahead) */
4737 		if (plarr == NULL) {
4738 			ip->i_nextrio = pgoff;
4739 			(void) ufs_getpage_ra(vp, pgoff, seg, pgaddr);
4740 			pgoff += pgsize;
4741 			pgaddr += pgsize;
4742 			continue;
4743 		}
4744 		/*
4745 		 * Check if we should initiate read ahead of next cluster.
4746 		 * We call page_exists only when we need to confirm that
4747 		 * we have the current page before we initiate the read ahead.
4748 		 */
4749 		nextrio = ip->i_nextrio;
4750 		if (seqmode &&
4751 		    pgoff + CLUSTSZ(ip) >= nextrio && pgoff <= nextrio &&
4752 		    nextrio < ip->i_size && page_exists(vp, pgoff)) {
4753 			retval = ufs_getpage_ra(vp, pgoff, seg, pgaddr);
4754 			/*
4755 			 * We always read ahead the next cluster of data
4756 			 * starting from i_nextrio. If the page (vp,nextrio)
4757 			 * is actually in core at this point, the routine
4758 			 * ufs_getpage_ra() will stop pre-fetching data
4759 			 * until we read that page in a synchronized manner
4760 			 * through ufs_getpage_miss(). So, we should increase
4761 			 * i_nextrio if the page (vp, nextrio) exists.
4762 			 */
4763 			if ((retval == 0) && page_exists(vp, nextrio)) {
4764 				ip->i_nextrio = nextrio + pgsize;
4765 			}
4766 		}
4767 
4768 		if ((pp = page_lookup(vp, pgoff, se)) != NULL) {
4769 			/*
4770 			 * We found the page in the page cache.
4771 			 */
4772 			*pl++ = pp;
4773 			pgoff += pgsize;
4774 			pgaddr += pgsize;
4775 			len -= pgsize;
4776 			plsz -= pgsize;
4777 		} else  {
4778 			/*
4779 			 * We have to create the page, or read it from disk.
4780 			 */
4781 			if (err = ufs_getpage_miss(vp, pgoff, len, seg, pgaddr,
4782 			    pl, plsz, rw, seqmode))
4783 				goto error;
4784 
4785 			while (*pl != NULL) {
4786 				pl++;
4787 				pgoff += pgsize;
4788 				pgaddr += pgsize;
4789 				len -= pgsize;
4790 				plsz -= pgsize;
4791 			}
4792 		}
4793 	}
4794 
4795 	/*
4796 	 * Return pages up to plsz if they are in the page cache.
4797 	 * We cannot return pages if there is a chance that they are
4798 	 * backed with a UFS hole and rw is S_WRITE or S_CREATE.
4799 	 */
4800 	if (plarr && !(has_holes && (rw == S_WRITE || rw == S_CREATE))) {
4801 
4802 		ASSERT((protp == NULL) ||
4803 		    !(has_holes && (*protp & PROT_WRITE)));
4804 
4805 		eoff = pgoff + plsz;
4806 		while (pgoff < eoff) {
4807 			page_t		*pp;
4808 
4809 			if ((pp = page_lookup_nowait(vp, pgoff,
4810 			    SE_SHARED)) == NULL)
4811 				break;
4812 
4813 			*pl++ = pp;
4814 			pgoff += pgsize;
4815 			plsz -= pgsize;
4816 		}
4817 	}
4818 
4819 	if (plarr)
4820 		*pl = NULL;			/* Terminate page list */
4821 	ip->i_nextr = pgoff;
4822 
4823 error:
4824 	if (err && plarr) {
4825 		/*
4826 		 * Release any pages we have locked.
4827 		 */
4828 		while (pl > &plarr[0])
4829 			page_unlock(*--pl);
4830 
4831 		plarr[0] = NULL;
4832 	}
4833 
4834 update_inode:
4835 	/*
4836 	 * If the inode is not already marked for IACC (in rdip() for read)
4837 	 * and the inode is not marked for no access time update (in wrip()
4838 	 * for write) then update the inode access time and mod time now.
4839 	 */
4840 	if ((ip->i_flag & (IACC | INOACC)) == 0) {
4841 		if ((rw != S_OTHER) && (ip->i_mode & IFMT) != IFDIR) {
4842 			if (!ULOCKFS_IS_NOIACC(ITOUL(ip)) &&
4843 			    (fs->fs_ronly == 0) &&
4844 			    (!ufsvfsp->vfs_noatime)) {
4845 				mutex_enter(&ip->i_tlock);
4846 				ip->i_flag |= IACC;
4847 				ITIMES_NOLOCK(ip);
4848 				mutex_exit(&ip->i_tlock);
4849 			}
4850 		}
4851 	}
4852 
4853 	if (dolock) {
4854 		rw_exit(&ip->i_contents);
4855 		if (do_qlock && rwtype == RW_WRITER)
4856 			rw_exit(&ufsvfsp->vfs_dqrwlock);
4857 	}
4858 
4859 unlock:
4860 	if (ulp) {
4861 		if ((rw == S_CREATE || rw == S_WRITE) &&
4862 		    !(vp->v_flag & VISSWAP)) {
4863 			TRANS_END_ASYNC(ufsvfsp, TOP_GETPAGE, trans_size);
4864 		}
4865 		ufs_lockfs_end(ulp);
4866 	}
4867 out:
4868 	return (err);
4869 }
4870 
4871 /*
4872  * ufs_getpage_miss is called when ufs_getpage missed the page in the page
4873  * cache. The page is either read from the disk, or it's created.
4874  * A page is created (without disk read) if rw == S_CREATE, or if
4875  * the page is not backed with a real disk block (UFS hole).
4876  */
4877 /* ARGSUSED */
4878 static int
ufs_getpage_miss(struct vnode * vp,u_offset_t off,size_t len,struct seg * seg,caddr_t addr,page_t * pl[],size_t plsz,enum seg_rw rw,int seq)4879 ufs_getpage_miss(struct vnode *vp, u_offset_t off, size_t len, struct seg *seg,
4880 	caddr_t addr, page_t *pl[], size_t plsz, enum seg_rw rw, int seq)
4881 {
4882 	struct inode	*ip = VTOI(vp);
4883 	page_t		*pp;
4884 	daddr_t		bn;
4885 	size_t		io_len;
4886 	int		crpage = 0;
4887 	int		err;
4888 	int		contig;
4889 	int		bsize = ip->i_fs->fs_bsize;
4890 
4891 	/*
4892 	 * Figure out whether the page can be created, or must be
4893 	 * must be read from the disk.
4894 	 */
4895 	if (rw == S_CREATE)
4896 		crpage = 1;
4897 	else {
4898 		contig = 0;
4899 		if (err = bmap_read(ip, off, &bn, &contig))
4900 			return (err);
4901 
4902 		crpage = (bn == UFS_HOLE);
4903 
4904 		/*
4905 		 * If its also a fallocated block that hasn't been written to
4906 		 * yet, we will treat it just like a UFS_HOLE and create
4907 		 * a zero page for it
4908 		 */
4909 		if (ISFALLOCBLK(ip, bn))
4910 			crpage = 1;
4911 	}
4912 
4913 	if (crpage) {
4914 		if ((pp = page_create_va(vp, off, PAGESIZE, PG_WAIT, seg,
4915 		    addr)) == NULL) {
4916 			return (ufs_fault(vp,
4917 			    "ufs_getpage_miss: page_create == NULL"));
4918 		}
4919 
4920 		if (rw != S_CREATE)
4921 			pagezero(pp, 0, PAGESIZE);
4922 
4923 		io_len = PAGESIZE;
4924 	} else {
4925 		u_offset_t	io_off;
4926 		uint_t	xlen;
4927 		struct buf	*bp;
4928 		ufsvfs_t	*ufsvfsp = ip->i_ufsvfs;
4929 
4930 		/*
4931 		 * If access is not in sequential order, we read from disk
4932 		 * in bsize units.
4933 		 *
4934 		 * We limit the size of the transfer to bsize if we are reading
4935 		 * from the beginning of the file. Note in this situation we
4936 		 * will hedge our bets and initiate an async read ahead of
4937 		 * the second block.
4938 		 */
4939 		if (!seq || off == 0)
4940 			contig = MIN(contig, bsize);
4941 
4942 		pp = pvn_read_kluster(vp, off, seg, addr, &io_off,
4943 		    &io_len, off, contig, 0);
4944 
4945 		/*
4946 		 * Some other thread has entered the page.
4947 		 * ufs_getpage will retry page_lookup.
4948 		 */
4949 		if (pp == NULL) {
4950 			pl[0] = NULL;
4951 			return (0);
4952 		}
4953 
4954 		/*
4955 		 * Zero part of the page which we are not
4956 		 * going to read from the disk.
4957 		 */
4958 		xlen = io_len & PAGEOFFSET;
4959 		if (xlen != 0)
4960 			pagezero(pp->p_prev, xlen, PAGESIZE - xlen);
4961 
4962 		bp = pageio_setup(pp, io_len, ip->i_devvp, B_READ);
4963 		bp->b_edev = ip->i_dev;
4964 		bp->b_dev = cmpdev(ip->i_dev);
4965 		bp->b_blkno = bn;
4966 		bp->b_un.b_addr = (caddr_t)0;
4967 		bp->b_file = ip->i_vnode;
4968 		bp->b_offset = off;
4969 
4970 		if (ufsvfsp->vfs_log) {
4971 			lufs_read_strategy(ufsvfsp->vfs_log, bp);
4972 		} else if (ufsvfsp->vfs_snapshot) {
4973 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
4974 		} else {
4975 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
4976 			ub.ub_getpages.value.ul++;
4977 			(void) bdev_strategy(bp);
4978 			lwp_stat_update(LWP_STAT_INBLK, 1);
4979 		}
4980 
4981 		ip->i_nextrio = off + ((io_len + PAGESIZE - 1) & PAGEMASK);
4982 
4983 		/*
4984 		 * If the file access is sequential, initiate read ahead
4985 		 * of the next cluster.
4986 		 */
4987 		if (seq && ip->i_nextrio < ip->i_size)
4988 			(void) ufs_getpage_ra(vp, off, seg, addr);
4989 		err = biowait(bp);
4990 		pageio_done(bp);
4991 
4992 		if (err) {
4993 			pvn_read_done(pp, B_ERROR);
4994 			return (err);
4995 		}
4996 	}
4997 
4998 	pvn_plist_init(pp, pl, plsz, off, io_len, rw);
4999 	return (0);
5000 }
5001 
5002 /*
5003  * Read ahead a cluster from the disk. Returns the length in bytes.
5004  */
5005 static int
ufs_getpage_ra(struct vnode * vp,u_offset_t off,struct seg * seg,caddr_t addr)5006 ufs_getpage_ra(struct vnode *vp, u_offset_t off, struct seg *seg, caddr_t addr)
5007 {
5008 	struct inode	*ip = VTOI(vp);
5009 	page_t		*pp;
5010 	u_offset_t	io_off = ip->i_nextrio;
5011 	ufsvfs_t	*ufsvfsp;
5012 	caddr_t		addr2 = addr + (io_off - off);
5013 	struct buf	*bp;
5014 	daddr_t		bn;
5015 	size_t		io_len;
5016 	int		err;
5017 	int		contig;
5018 	int		xlen;
5019 	int		bsize = ip->i_fs->fs_bsize;
5020 
5021 	/*
5022 	 * If the directio advisory is in effect on this file,
5023 	 * then do not do buffered read ahead. Read ahead makes
5024 	 * it more difficult on threads using directio as they
5025 	 * will be forced to flush the pages from this vnode.
5026 	 */
5027 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
5028 		return (0);
5029 	if (ip->i_flag & IDIRECTIO || ufsvfsp->vfs_forcedirectio)
5030 		return (0);
5031 
5032 	/*
5033 	 * Is this test needed?
5034 	 */
5035 	if (addr2 >= seg->s_base + seg->s_size)
5036 		return (0);
5037 
5038 	contig = 0;
5039 	err = bmap_read(ip, io_off, &bn, &contig);
5040 	/*
5041 	 * If its a UFS_HOLE or a fallocated block, do not perform
5042 	 * any read ahead's since there probably is nothing to read ahead
5043 	 */
5044 	if (err || bn == UFS_HOLE || ISFALLOCBLK(ip, bn))
5045 		return (0);
5046 
5047 	/*
5048 	 * Limit the transfer size to bsize if this is the 2nd block.
5049 	 */
5050 	if (io_off == (u_offset_t)bsize)
5051 		contig = MIN(contig, bsize);
5052 
5053 	if ((pp = pvn_read_kluster(vp, io_off, seg, addr2, &io_off,
5054 	    &io_len, io_off, contig, 1)) == NULL)
5055 		return (0);
5056 
5057 	/*
5058 	 * Zero part of page which we are not going to read from disk
5059 	 */
5060 	if ((xlen = (io_len & PAGEOFFSET)) > 0)
5061 		pagezero(pp->p_prev, xlen, PAGESIZE - xlen);
5062 
5063 	ip->i_nextrio = (io_off + io_len + PAGESIZE - 1) & PAGEMASK;
5064 
5065 	bp = pageio_setup(pp, io_len, ip->i_devvp, B_READ | B_ASYNC);
5066 	bp->b_edev = ip->i_dev;
5067 	bp->b_dev = cmpdev(ip->i_dev);
5068 	bp->b_blkno = bn;
5069 	bp->b_un.b_addr = (caddr_t)0;
5070 	bp->b_file = ip->i_vnode;
5071 	bp->b_offset = off;
5072 
5073 	if (ufsvfsp->vfs_log) {
5074 		lufs_read_strategy(ufsvfsp->vfs_log, bp);
5075 	} else if (ufsvfsp->vfs_snapshot) {
5076 		fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
5077 	} else {
5078 		ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5079 		ub.ub_getras.value.ul++;
5080 		(void) bdev_strategy(bp);
5081 		lwp_stat_update(LWP_STAT_INBLK, 1);
5082 	}
5083 
5084 	return (io_len);
5085 }
5086 
5087 int	ufs_delay = 1;
5088 /*
5089  * Flags are composed of {B_INVAL, B_FREE, B_DONTNEED, B_FORCE, B_ASYNC}
5090  *
5091  * LMXXX - the inode really ought to contain a pointer to one of these
5092  * async args.  Stuff gunk in there and just hand the whole mess off.
5093  * This would replace i_delaylen, i_delayoff.
5094  */
5095 /*ARGSUSED*/
5096 static int
ufs_putpage(struct vnode * vp,offset_t off,size_t len,int flags,struct cred * cr,caller_context_t * ct)5097 ufs_putpage(struct vnode *vp, offset_t off, size_t len, int flags,
5098 	struct cred *cr, caller_context_t *ct)
5099 {
5100 	struct inode *ip = VTOI(vp);
5101 	int err = 0;
5102 
5103 	if (vp->v_count == 0) {
5104 		return (ufs_fault(vp, "ufs_putpage: bad v_count == 0"));
5105 	}
5106 
5107 	/*
5108 	 * XXX - Why should this check be made here?
5109 	 */
5110 	if (vp->v_flag & VNOMAP) {
5111 		err = ENOSYS;
5112 		goto errout;
5113 	}
5114 
5115 	if (ip->i_ufsvfs == NULL) {
5116 		err = EIO;
5117 		goto errout;
5118 	}
5119 
5120 	if (flags & B_ASYNC) {
5121 		if (ufs_delay && len &&
5122 		    (flags & ~(B_ASYNC|B_DONTNEED|B_FREE)) == 0) {
5123 			mutex_enter(&ip->i_tlock);
5124 			/*
5125 			 * If nobody stalled, start a new cluster.
5126 			 */
5127 			if (ip->i_delaylen == 0) {
5128 				ip->i_delayoff = off;
5129 				ip->i_delaylen = len;
5130 				mutex_exit(&ip->i_tlock);
5131 				goto errout;
5132 			}
5133 			/*
5134 			 * If we have a full cluster or they are not contig,
5135 			 * then push last cluster and start over.
5136 			 */
5137 			if (ip->i_delaylen >= CLUSTSZ(ip) ||
5138 			    ip->i_delayoff + ip->i_delaylen != off) {
5139 				u_offset_t doff;
5140 				size_t dlen;
5141 
5142 				doff = ip->i_delayoff;
5143 				dlen = ip->i_delaylen;
5144 				ip->i_delayoff = off;
5145 				ip->i_delaylen = len;
5146 				mutex_exit(&ip->i_tlock);
5147 				err = ufs_putpages(vp, doff, dlen,
5148 				    flags, cr);
5149 				/* LMXXX - flags are new val, not old */
5150 				goto errout;
5151 			}
5152 			/*
5153 			 * There is something there, it's not full, and
5154 			 * it is contig.
5155 			 */
5156 			ip->i_delaylen += len;
5157 			mutex_exit(&ip->i_tlock);
5158 			goto errout;
5159 		}
5160 		/*
5161 		 * Must have weird flags or we are not clustering.
5162 		 */
5163 	}
5164 
5165 	err = ufs_putpages(vp, off, len, flags, cr);
5166 
5167 errout:
5168 	return (err);
5169 }
5170 
5171 /*
5172  * If len == 0, do from off to EOF.
5173  *
5174  * The normal cases should be len == 0 & off == 0 (entire vp list),
5175  * len == MAXBSIZE (from segmap_release actions), and len == PAGESIZE
5176  * (from pageout).
5177  */
5178 /*ARGSUSED*/
5179 static int
ufs_putpages(struct vnode * vp,offset_t off,size_t len,int flags,struct cred * cr)5180 ufs_putpages(
5181 	struct vnode *vp,
5182 	offset_t off,
5183 	size_t len,
5184 	int flags,
5185 	struct cred *cr)
5186 {
5187 	u_offset_t io_off;
5188 	u_offset_t eoff;
5189 	struct inode *ip = VTOI(vp);
5190 	page_t *pp;
5191 	size_t io_len;
5192 	int err = 0;
5193 	int dolock;
5194 
5195 	if (vp->v_count == 0)
5196 		return (ufs_fault(vp, "ufs_putpages: v_count == 0"));
5197 	/*
5198 	 * Acquire the readers/write inode lock before locking
5199 	 * any pages in this inode.
5200 	 * The inode lock is held during i/o.
5201 	 */
5202 	if (len == 0) {
5203 		mutex_enter(&ip->i_tlock);
5204 		ip->i_delayoff = ip->i_delaylen = 0;
5205 		mutex_exit(&ip->i_tlock);
5206 	}
5207 	dolock = (rw_owner(&ip->i_contents) != curthread);
5208 	if (dolock) {
5209 		/*
5210 		 * Must synchronize this thread and any possible thread
5211 		 * operating in the window of vulnerability in wrip().
5212 		 * It is dangerous to allow both a thread doing a putpage
5213 		 * and a thread writing, so serialize them.  The exception
5214 		 * is when the thread in wrip() does something which causes
5215 		 * a putpage operation.  Then, the thread must be allowed
5216 		 * to continue.  It may encounter a bmap_read problem in
5217 		 * ufs_putapage, but that is handled in ufs_putapage.
5218 		 * Allow async writers to proceed, we don't want to block
5219 		 * the pageout daemon.
5220 		 */
5221 		if (ip->i_writer == curthread)
5222 			rw_enter(&ip->i_contents, RW_READER);
5223 		else {
5224 			for (;;) {
5225 				rw_enter(&ip->i_contents, RW_READER);
5226 				mutex_enter(&ip->i_tlock);
5227 				/*
5228 				 * If there is no thread in the critical
5229 				 * section of wrip(), then proceed.
5230 				 * Otherwise, wait until there isn't one.
5231 				 */
5232 				if (ip->i_writer == NULL) {
5233 					mutex_exit(&ip->i_tlock);
5234 					break;
5235 				}
5236 				rw_exit(&ip->i_contents);
5237 				/*
5238 				 * Bounce async writers when we have a writer
5239 				 * working on this file so we don't deadlock
5240 				 * the pageout daemon.
5241 				 */
5242 				if (flags & B_ASYNC) {
5243 					mutex_exit(&ip->i_tlock);
5244 					return (0);
5245 				}
5246 				cv_wait(&ip->i_wrcv, &ip->i_tlock);
5247 				mutex_exit(&ip->i_tlock);
5248 			}
5249 		}
5250 	}
5251 
5252 	if (!vn_has_cached_data(vp)) {
5253 		if (dolock)
5254 			rw_exit(&ip->i_contents);
5255 		return (0);
5256 	}
5257 
5258 	if (len == 0) {
5259 		/*
5260 		 * Search the entire vp list for pages >= off.
5261 		 */
5262 		err = pvn_vplist_dirty(vp, (u_offset_t)off, ufs_putapage,
5263 		    flags, cr);
5264 	} else {
5265 		/*
5266 		 * Loop over all offsets in the range looking for
5267 		 * pages to deal with.
5268 		 */
5269 		if ((eoff = blkroundup(ip->i_fs, ip->i_size)) != 0)
5270 			eoff = MIN(off + len, eoff);
5271 		else
5272 			eoff = off + len;
5273 
5274 		for (io_off = off; io_off < eoff; io_off += io_len) {
5275 			/*
5276 			 * If we are not invalidating, synchronously
5277 			 * freeing or writing pages, use the routine
5278 			 * page_lookup_nowait() to prevent reclaiming
5279 			 * them from the free list.
5280 			 */
5281 			if ((flags & B_INVAL) || ((flags & B_ASYNC) == 0)) {
5282 				pp = page_lookup(vp, io_off,
5283 				    (flags & (B_INVAL | B_FREE)) ?
5284 				    SE_EXCL : SE_SHARED);
5285 			} else {
5286 				pp = page_lookup_nowait(vp, io_off,
5287 				    (flags & B_FREE) ? SE_EXCL : SE_SHARED);
5288 			}
5289 
5290 			if (pp == NULL || pvn_getdirty(pp, flags) == 0)
5291 				io_len = PAGESIZE;
5292 			else {
5293 				u_offset_t *io_offp = &io_off;
5294 
5295 				err = ufs_putapage(vp, pp, io_offp, &io_len,
5296 				    flags, cr);
5297 				if (err != 0)
5298 					break;
5299 				/*
5300 				 * "io_off" and "io_len" are returned as
5301 				 * the range of pages we actually wrote.
5302 				 * This allows us to skip ahead more quickly
5303 				 * since several pages may've been dealt
5304 				 * with by this iteration of the loop.
5305 				 */
5306 			}
5307 		}
5308 	}
5309 	if (err == 0 && off == 0 && (len == 0 || len >= ip->i_size)) {
5310 		/*
5311 		 * We have just sync'ed back all the pages on
5312 		 * the inode, turn off the IMODTIME flag.
5313 		 */
5314 		mutex_enter(&ip->i_tlock);
5315 		ip->i_flag &= ~IMODTIME;
5316 		mutex_exit(&ip->i_tlock);
5317 	}
5318 	if (dolock)
5319 		rw_exit(&ip->i_contents);
5320 	return (err);
5321 }
5322 
5323 static void
ufs_iodone(buf_t * bp)5324 ufs_iodone(buf_t *bp)
5325 {
5326 	struct inode *ip;
5327 
5328 	ASSERT((bp->b_pages->p_vnode != NULL) && !(bp->b_flags & B_READ));
5329 
5330 	bp->b_iodone = NULL;
5331 
5332 	ip = VTOI(bp->b_pages->p_vnode);
5333 
5334 	mutex_enter(&ip->i_tlock);
5335 	if (ip->i_writes >= ufs_LW) {
5336 		if ((ip->i_writes -= bp->b_bcount) <= ufs_LW)
5337 			if (ufs_WRITES)
5338 				cv_broadcast(&ip->i_wrcv); /* wake all up */
5339 	} else {
5340 		ip->i_writes -= bp->b_bcount;
5341 	}
5342 
5343 	mutex_exit(&ip->i_tlock);
5344 	iodone(bp);
5345 }
5346 
5347 /*
5348  * Write out a single page, possibly klustering adjacent
5349  * dirty pages.  The inode lock must be held.
5350  *
5351  * LMXXX - bsize < pagesize not done.
5352  */
5353 /*ARGSUSED*/
5354 int
ufs_putapage(struct vnode * vp,page_t * pp,u_offset_t * offp,size_t * lenp,int flags,struct cred * cr)5355 ufs_putapage(
5356 	struct vnode *vp,
5357 	page_t *pp,
5358 	u_offset_t *offp,
5359 	size_t *lenp,		/* return values */
5360 	int flags,
5361 	struct cred *cr)
5362 {
5363 	u_offset_t io_off;
5364 	u_offset_t off;
5365 	struct inode *ip = VTOI(vp);
5366 	struct ufsvfs *ufsvfsp = ip->i_ufsvfs;
5367 	struct fs *fs;
5368 	struct buf *bp;
5369 	size_t io_len;
5370 	daddr_t bn;
5371 	int err;
5372 	int contig;
5373 	int dotrans;
5374 
5375 	ASSERT(RW_LOCK_HELD(&ip->i_contents));
5376 
5377 	if (ufsvfsp == NULL) {
5378 		err = EIO;
5379 		goto out_trace;
5380 	}
5381 
5382 	fs = ip->i_fs;
5383 	ASSERT(fs->fs_ronly == 0);
5384 
5385 	/*
5386 	 * If the modified time on the inode has not already been
5387 	 * set elsewhere (e.g. for write/setattr) we set the time now.
5388 	 * This gives us approximate modified times for mmap'ed files
5389 	 * which are modified via stores in the user address space.
5390 	 */
5391 	if ((ip->i_flag & IMODTIME) == 0) {
5392 		mutex_enter(&ip->i_tlock);
5393 		ip->i_flag |= IUPD;
5394 		ip->i_seq++;
5395 		ITIMES_NOLOCK(ip);
5396 		mutex_exit(&ip->i_tlock);
5397 	}
5398 
5399 	/*
5400 	 * Align the request to a block boundry (for old file systems),
5401 	 * and go ask bmap() how contiguous things are for this file.
5402 	 */
5403 	off = pp->p_offset & (offset_t)fs->fs_bmask;	/* block align it */
5404 	contig = 0;
5405 	err = bmap_read(ip, off, &bn, &contig);
5406 	if (err)
5407 		goto out;
5408 	if (bn == UFS_HOLE) {			/* putpage never allocates */
5409 		/*
5410 		 * logging device is in error mode; simply return EIO
5411 		 */
5412 		if (TRANS_ISERROR(ufsvfsp)) {
5413 			err = EIO;
5414 			goto out;
5415 		}
5416 		/*
5417 		 * Oops, the thread in the window in wrip() did some
5418 		 * sort of operation which caused a putpage in the bad
5419 		 * range.  In this case, just return an error which will
5420 		 * cause the software modified bit on the page to set
5421 		 * and the page will get written out again later.
5422 		 */
5423 		if (ip->i_writer == curthread) {
5424 			err = EIO;
5425 			goto out;
5426 		}
5427 		/*
5428 		 * If the pager is trying to push a page in the bad range
5429 		 * just tell him to try again later when things are better.
5430 		 */
5431 		if (flags & B_ASYNC) {
5432 			err = EAGAIN;
5433 			goto out;
5434 		}
5435 		err = ufs_fault(ITOV(ip), "ufs_putapage: bn == UFS_HOLE");
5436 		goto out;
5437 	}
5438 
5439 	/*
5440 	 * If it is an fallocate'd block, reverse the negativity since
5441 	 * we are now writing to it
5442 	 */
5443 	if (ISFALLOCBLK(ip, bn)) {
5444 		err = bmap_set_bn(vp, off, dbtofsb(fs, -bn));
5445 		if (err)
5446 			goto out;
5447 
5448 		bn = -bn;
5449 	}
5450 
5451 	/*
5452 	 * Take the length (of contiguous bytes) passed back from bmap()
5453 	 * and _try_ and get a set of pages covering that extent.
5454 	 */
5455 	pp = pvn_write_kluster(vp, pp, &io_off, &io_len, off, contig, flags);
5456 
5457 	/*
5458 	 * May have run out of memory and not clustered backwards.
5459 	 * off		p_offset
5460 	 * [  pp - 1  ][   pp   ]
5461 	 * [	block		]
5462 	 * We told bmap off, so we have to adjust the bn accordingly.
5463 	 */
5464 	if (io_off > off) {
5465 		bn += btod(io_off - off);
5466 		contig -= (io_off - off);
5467 	}
5468 
5469 	/*
5470 	 * bmap was carefull to tell us the right size so use that.
5471 	 * There might be unallocated frags at the end.
5472 	 * LMXXX - bzero the end of the page?  We must be writing after EOF.
5473 	 */
5474 	if (io_len > contig) {
5475 		ASSERT(io_len - contig < fs->fs_bsize);
5476 		io_len -= (io_len - contig);
5477 	}
5478 
5479 	/*
5480 	 * Handle the case where we are writing the last page after EOF.
5481 	 *
5482 	 * XXX - just a patch for i-mt3.
5483 	 */
5484 	if (io_len == 0) {
5485 		ASSERT(pp->p_offset >=
5486 		    (u_offset_t)(roundup(ip->i_size, PAGESIZE)));
5487 		io_len = PAGESIZE;
5488 	}
5489 
5490 	bp = pageio_setup(pp, io_len, ip->i_devvp, B_WRITE | flags);
5491 
5492 	ULOCKFS_SET_MOD(ITOUL(ip));
5493 
5494 	bp->b_edev = ip->i_dev;
5495 	bp->b_dev = cmpdev(ip->i_dev);
5496 	bp->b_blkno = bn;
5497 	bp->b_un.b_addr = (caddr_t)0;
5498 	bp->b_file = ip->i_vnode;
5499 
5500 	/*
5501 	 * File contents of shadow or quota inodes are metadata, and updates
5502 	 * to these need to be put into a logging transaction. All direct
5503 	 * callers in UFS do that, but fsflush can come here _before_ the
5504 	 * normal codepath. An example would be updating ACL information, for
5505 	 * which the normal codepath would be:
5506 	 *	ufs_si_store()
5507 	 *	ufs_rdwri()
5508 	 *	wrip()
5509 	 *	segmap_release()
5510 	 *	VOP_PUTPAGE()
5511 	 * Here, fsflush can pick up the dirty page before segmap_release()
5512 	 * forces it out. If that happens, there's no transaction.
5513 	 * We therefore need to test whether a transaction exists, and if not
5514 	 * create one - for fsflush.
5515 	 */
5516 	dotrans =
5517 	    (((ip->i_mode & IFMT) == IFSHAD || ufsvfsp->vfs_qinod == ip) &&
5518 	    ((curthread->t_flag & T_DONTBLOCK) == 0) &&
5519 	    (TRANS_ISTRANS(ufsvfsp)));
5520 
5521 	if (dotrans) {
5522 		curthread->t_flag |= T_DONTBLOCK;
5523 		TRANS_BEGIN_ASYNC(ufsvfsp, TOP_PUTPAGE, TOP_PUTPAGE_SIZE(ip));
5524 	}
5525 	if (TRANS_ISTRANS(ufsvfsp)) {
5526 		if ((ip->i_mode & IFMT) == IFSHAD) {
5527 			TRANS_BUF(ufsvfsp, 0, io_len, bp, DT_SHAD);
5528 		} else if (ufsvfsp->vfs_qinod == ip) {
5529 			TRANS_DELTA(ufsvfsp, ldbtob(bn), bp->b_bcount, DT_QR,
5530 			    0, 0);
5531 		}
5532 	}
5533 	if (dotrans) {
5534 		TRANS_END_ASYNC(ufsvfsp, TOP_PUTPAGE, TOP_PUTPAGE_SIZE(ip));
5535 		curthread->t_flag &= ~T_DONTBLOCK;
5536 	}
5537 
5538 	/* write throttle */
5539 
5540 	ASSERT(bp->b_iodone == NULL);
5541 	bp->b_iodone = (int (*)())ufs_iodone;
5542 	mutex_enter(&ip->i_tlock);
5543 	ip->i_writes += bp->b_bcount;
5544 	mutex_exit(&ip->i_tlock);
5545 
5546 	if (bp->b_flags & B_ASYNC) {
5547 		if (ufsvfsp->vfs_log) {
5548 			lufs_write_strategy(ufsvfsp->vfs_log, bp);
5549 		} else if (ufsvfsp->vfs_snapshot) {
5550 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
5551 		} else {
5552 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5553 			ub.ub_putasyncs.value.ul++;
5554 			(void) bdev_strategy(bp);
5555 			lwp_stat_update(LWP_STAT_OUBLK, 1);
5556 		}
5557 	} else {
5558 		if (ufsvfsp->vfs_log) {
5559 			lufs_write_strategy(ufsvfsp->vfs_log, bp);
5560 		} else if (ufsvfsp->vfs_snapshot) {
5561 			fssnap_strategy(&ufsvfsp->vfs_snapshot, bp);
5562 		} else {
5563 			ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
5564 			ub.ub_putsyncs.value.ul++;
5565 			(void) bdev_strategy(bp);
5566 			lwp_stat_update(LWP_STAT_OUBLK, 1);
5567 		}
5568 		err = biowait(bp);
5569 		pageio_done(bp);
5570 		pvn_write_done(pp, ((err) ? B_ERROR : 0) | B_WRITE | flags);
5571 	}
5572 
5573 	pp = NULL;
5574 
5575 out:
5576 	if (err != 0 && pp != NULL)
5577 		pvn_write_done(pp, B_ERROR | B_WRITE | flags);
5578 
5579 	if (offp)
5580 		*offp = io_off;
5581 	if (lenp)
5582 		*lenp = io_len;
5583 out_trace:
5584 	return (err);
5585 }
5586 
5587 uint64_t ufs_map_alock_retry_cnt;
5588 uint64_t ufs_map_lockfs_retry_cnt;
5589 
5590 /* ARGSUSED */
5591 static int
ufs_map(struct vnode * vp,offset_t off,struct as * as,caddr_t * addrp,size_t len,uchar_t prot,uchar_t maxprot,uint_t flags,struct cred * cr,caller_context_t * ct)5592 ufs_map(struct vnode *vp,
5593 	offset_t off,
5594 	struct as *as,
5595 	caddr_t *addrp,
5596 	size_t len,
5597 	uchar_t prot,
5598 	uchar_t maxprot,
5599 	uint_t flags,
5600 	struct cred *cr,
5601 	caller_context_t *ct)
5602 {
5603 	struct segvn_crargs vn_a;
5604 	struct ufsvfs *ufsvfsp = VTOI(vp)->i_ufsvfs;
5605 	struct ulockfs *ulp;
5606 	int error, sig;
5607 	k_sigset_t smask;
5608 	caddr_t hint = *addrp;
5609 
5610 	if (vp->v_flag & VNOMAP) {
5611 		error = ENOSYS;
5612 		goto out;
5613 	}
5614 
5615 	if (off < (offset_t)0 || (offset_t)(off + len) < (offset_t)0) {
5616 		error = ENXIO;
5617 		goto out;
5618 	}
5619 
5620 	if (vp->v_type != VREG) {
5621 		error = ENODEV;
5622 		goto out;
5623 	}
5624 
5625 retry_map:
5626 	*addrp = hint;
5627 	/*
5628 	 * If file is being locked, disallow mapping.
5629 	 */
5630 	if (vn_has_mandatory_locks(vp, VTOI(vp)->i_mode)) {
5631 		error = EAGAIN;
5632 		goto out;
5633 	}
5634 
5635 	as_rangelock(as);
5636 	/*
5637 	 * Note that if we are retrying (because ufs_lockfs_trybegin failed in
5638 	 * the previous attempt), some other thread could have grabbed
5639 	 * the same VA range if MAP_FIXED is set. In that case, choose_addr
5640 	 * would unmap the valid VA range, that is ok.
5641 	 */
5642 	error = choose_addr(as, addrp, len, off, ADDR_VACALIGN, flags);
5643 	if (error != 0) {
5644 		as_rangeunlock(as);
5645 		goto out;
5646 	}
5647 
5648 	/*
5649 	 * a_lock has to be acquired before entering the lockfs protocol
5650 	 * because that is the order in which pagefault works. Also we cannot
5651 	 * block on a_lock here because this waiting writer will prevent
5652 	 * further readers like ufs_read from progressing and could cause
5653 	 * deadlock between ufs_read/ufs_map/pagefault when a quiesce is
5654 	 * pending.
5655 	 */
5656 	while (!AS_LOCK_TRYENTER(as, RW_WRITER)) {
5657 		ufs_map_alock_retry_cnt++;
5658 		delay(RETRY_LOCK_DELAY);
5659 	}
5660 
5661 	/*
5662 	 * We can't hold as->a_lock and wait for lockfs to succeed because
5663 	 * the proc tools might hang on a_lock, so call ufs_lockfs_trybegin()
5664 	 * instead.
5665 	 */
5666 	if (error = ufs_lockfs_trybegin(ufsvfsp, &ulp, ULOCKFS_MAP_MASK)) {
5667 		/*
5668 		 * ufs_lockfs_trybegin() did not succeed. It is safer to give up
5669 		 * as->a_lock and wait for ulp->ul_fs_lock status to change.
5670 		 */
5671 		ufs_map_lockfs_retry_cnt++;
5672 		AS_LOCK_EXIT(as);
5673 		as_rangeunlock(as);
5674 		if (error == EIO)
5675 			goto out;
5676 
5677 		mutex_enter(&ulp->ul_lock);
5678 		while (ulp->ul_fs_lock & ULOCKFS_MAP_MASK) {
5679 			if (ULOCKFS_IS_SLOCK(ulp) || ufsvfsp->vfs_nointr) {
5680 				cv_wait(&ulp->ul_cv, &ulp->ul_lock);
5681 			} else {
5682 				sigintr(&smask, 1);
5683 				sig = cv_wait_sig(&ulp->ul_cv, &ulp->ul_lock);
5684 				sigunintr(&smask);
5685 				if (((ulp->ul_fs_lock & ULOCKFS_MAP_MASK) &&
5686 				    !sig) || ufsvfsp->vfs_dontblock) {
5687 					mutex_exit(&ulp->ul_lock);
5688 					return (EINTR);
5689 				}
5690 			}
5691 		}
5692 		mutex_exit(&ulp->ul_lock);
5693 		goto retry_map;
5694 	}
5695 
5696 	vn_a.vp = vp;
5697 	vn_a.offset = (u_offset_t)off;
5698 	vn_a.type = flags & MAP_TYPE;
5699 	vn_a.prot = prot;
5700 	vn_a.maxprot = maxprot;
5701 	vn_a.cred = cr;
5702 	vn_a.amp = NULL;
5703 	vn_a.flags = flags & ~MAP_TYPE;
5704 	vn_a.szc = 0;
5705 	vn_a.lgrp_mem_policy_flags = 0;
5706 
5707 	error = as_map_locked(as, *addrp, len, segvn_create, &vn_a);
5708 	if (ulp)
5709 		ufs_lockfs_end(ulp);
5710 	as_rangeunlock(as);
5711 out:
5712 	return (error);
5713 }
5714 
5715 /* ARGSUSED */
5716 static int
ufs_addmap(struct vnode * vp,offset_t off,struct as * as,caddr_t addr,size_t len,uchar_t prot,uchar_t maxprot,uint_t flags,struct cred * cr,caller_context_t * ct)5717 ufs_addmap(struct vnode *vp,
5718 	offset_t off,
5719 	struct as *as,
5720 	caddr_t addr,
5721 	size_t	len,
5722 	uchar_t  prot,
5723 	uchar_t  maxprot,
5724 	uint_t    flags,
5725 	struct cred *cr,
5726 	caller_context_t *ct)
5727 {
5728 	struct inode *ip = VTOI(vp);
5729 
5730 	if (vp->v_flag & VNOMAP) {
5731 		return (ENOSYS);
5732 	}
5733 
5734 	mutex_enter(&ip->i_tlock);
5735 	ip->i_mapcnt += btopr(len);
5736 	mutex_exit(&ip->i_tlock);
5737 	return (0);
5738 }
5739 
5740 /*ARGSUSED*/
5741 static int
ufs_delmap(struct vnode * vp,offset_t off,struct as * as,caddr_t addr,size_t len,uint_t prot,uint_t maxprot,uint_t flags,struct cred * cr,caller_context_t * ct)5742 ufs_delmap(struct vnode *vp, offset_t off, struct as *as, caddr_t addr,
5743 	size_t len, uint_t prot,  uint_t maxprot,  uint_t flags,
5744 	struct cred *cr, caller_context_t *ct)
5745 {
5746 	struct inode *ip = VTOI(vp);
5747 
5748 	if (vp->v_flag & VNOMAP) {
5749 		return (ENOSYS);
5750 	}
5751 
5752 	mutex_enter(&ip->i_tlock);
5753 	ip->i_mapcnt -= btopr(len); 	/* Count released mappings */
5754 	ASSERT(ip->i_mapcnt >= 0);
5755 	mutex_exit(&ip->i_tlock);
5756 	return (0);
5757 }
5758 /*
5759  * Return the answer requested to poll() for non-device files
5760  */
5761 struct pollhead ufs_pollhd;
5762 
5763 /* ARGSUSED */
5764 int
ufs_poll(vnode_t * vp,short ev,int any,short * revp,struct pollhead ** phpp,caller_context_t * ct)5765 ufs_poll(vnode_t *vp, short ev, int any, short *revp, struct pollhead **phpp,
5766 	caller_context_t *ct)
5767 {
5768 	struct ufsvfs	*ufsvfsp;
5769 
5770 	*revp = 0;
5771 	ufsvfsp = VTOI(vp)->i_ufsvfs;
5772 
5773 	if (!ufsvfsp) {
5774 		*revp = POLLHUP;
5775 		goto out;
5776 	}
5777 
5778 	if (ULOCKFS_IS_HLOCK(&ufsvfsp->vfs_ulockfs) ||
5779 	    ULOCKFS_IS_ELOCK(&ufsvfsp->vfs_ulockfs)) {
5780 		*revp |= POLLERR;
5781 
5782 	} else {
5783 		if ((ev & POLLOUT) && !ufsvfsp->vfs_fs->fs_ronly &&
5784 		    !ULOCKFS_IS_WLOCK(&ufsvfsp->vfs_ulockfs))
5785 			*revp |= POLLOUT;
5786 
5787 		if ((ev & POLLWRBAND) && !ufsvfsp->vfs_fs->fs_ronly &&
5788 		    !ULOCKFS_IS_WLOCK(&ufsvfsp->vfs_ulockfs))
5789 			*revp |= POLLWRBAND;
5790 
5791 		if (ev & POLLIN)
5792 			*revp |= POLLIN;
5793 
5794 		if (ev & POLLRDNORM)
5795 			*revp |= POLLRDNORM;
5796 
5797 		if (ev & POLLRDBAND)
5798 			*revp |= POLLRDBAND;
5799 	}
5800 
5801 	if ((ev & POLLPRI) && (*revp & (POLLERR|POLLHUP)))
5802 		*revp |= POLLPRI;
5803 out:
5804 	*phpp = !any && !*revp ? &ufs_pollhd : (struct pollhead *)NULL;
5805 
5806 	return (0);
5807 }
5808 
5809 /* ARGSUSED */
5810 static int
ufs_l_pathconf(struct vnode * vp,int cmd,ulong_t * valp,struct cred * cr,caller_context_t * ct)5811 ufs_l_pathconf(struct vnode *vp, int cmd, ulong_t *valp, struct cred *cr,
5812 	caller_context_t *ct)
5813 {
5814 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
5815 	struct ulockfs	*ulp = NULL;
5816 	struct inode 	*sip = NULL;
5817 	int		error;
5818 	struct inode 	*ip = VTOI(vp);
5819 	int		issync;
5820 
5821 	error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_PATHCONF_MASK);
5822 	if (error)
5823 		return (error);
5824 
5825 	switch (cmd) {
5826 		/*
5827 		 * Have to handle _PC_NAME_MAX here, because the normal way
5828 		 * [fs_pathconf() -> VOP_STATVFS() -> ufs_statvfs()]
5829 		 * results in a lock ordering reversal between
5830 		 * ufs_lockfs_{begin,end}() and
5831 		 * ufs_thread_{suspend,continue}().
5832 		 *
5833 		 * Keep in sync with ufs_statvfs().
5834 		 */
5835 	case _PC_NAME_MAX:
5836 		*valp = MAXNAMLEN;
5837 		break;
5838 
5839 	case _PC_FILESIZEBITS:
5840 		if (ufsvfsp->vfs_lfflags & UFS_LARGEFILES)
5841 			*valp = UFS_FILESIZE_BITS;
5842 		else
5843 			*valp = 32;
5844 		break;
5845 
5846 	case _PC_XATTR_EXISTS:
5847 		if (vp->v_vfsp->vfs_flag & VFS_XATTR) {
5848 
5849 			error =
5850 			    ufs_xattr_getattrdir(vp, &sip, LOOKUP_XATTR, cr);
5851 			if (error ==  0 && sip != NULL) {
5852 				/* Start transaction */
5853 				if (ulp) {
5854 					TRANS_BEGIN_CSYNC(ufsvfsp, issync,
5855 					    TOP_RMDIR, TOP_RMDIR_SIZE);
5856 				}
5857 				/*
5858 				 * Is directory empty
5859 				 */
5860 				rw_enter(&sip->i_rwlock, RW_WRITER);
5861 				rw_enter(&sip->i_contents, RW_WRITER);
5862 				if (ufs_xattrdirempty(sip,
5863 				    sip->i_number, CRED())) {
5864 					rw_enter(&ip->i_contents, RW_WRITER);
5865 					ufs_unhook_shadow(ip, sip);
5866 					rw_exit(&ip->i_contents);
5867 
5868 					*valp = 0;
5869 
5870 				} else
5871 					*valp = 1;
5872 				rw_exit(&sip->i_contents);
5873 				rw_exit(&sip->i_rwlock);
5874 				if (ulp) {
5875 					TRANS_END_CSYNC(ufsvfsp, error, issync,
5876 					    TOP_RMDIR, TOP_RMDIR_SIZE);
5877 				}
5878 				VN_RELE(ITOV(sip));
5879 			} else if (error == ENOENT) {
5880 				*valp = 0;
5881 				error = 0;
5882 			}
5883 		} else {
5884 			error = fs_pathconf(vp, cmd, valp, cr, ct);
5885 		}
5886 		break;
5887 
5888 	case _PC_ACL_ENABLED:
5889 		*valp = _ACL_ACLENT_ENABLED;
5890 		break;
5891 
5892 	case _PC_MIN_HOLE_SIZE:
5893 		*valp = (ulong_t)ip->i_fs->fs_bsize;
5894 		break;
5895 
5896 	case _PC_SATTR_ENABLED:
5897 	case _PC_SATTR_EXISTS:
5898 		*valp = vfs_has_feature(vp->v_vfsp, VFSFT_SYSATTR_VIEWS) &&
5899 		    (vp->v_type == VREG || vp->v_type == VDIR);
5900 		break;
5901 
5902 	case _PC_TIMESTAMP_RESOLUTION:
5903 		/*
5904 		 * UFS keeps only microsecond timestamp resolution.
5905 		 * This is historical and will probably never change.
5906 		 */
5907 		*valp = 1000L;
5908 		break;
5909 
5910 	default:
5911 		error = fs_pathconf(vp, cmd, valp, cr, ct);
5912 		break;
5913 	}
5914 
5915 	if (ulp != NULL) {
5916 		ufs_lockfs_end(ulp);
5917 	}
5918 	return (error);
5919 }
5920 
5921 int ufs_pageio_writes, ufs_pageio_reads;
5922 
5923 /*ARGSUSED*/
5924 static int
ufs_pageio(struct vnode * vp,page_t * pp,u_offset_t io_off,size_t io_len,int flags,struct cred * cr,caller_context_t * ct)5925 ufs_pageio(struct vnode *vp, page_t *pp, u_offset_t io_off, size_t io_len,
5926 	int flags, struct cred *cr, caller_context_t *ct)
5927 {
5928 	struct inode *ip = VTOI(vp);
5929 	struct ufsvfs *ufsvfsp;
5930 	page_t *npp = NULL, *opp = NULL, *cpp = pp;
5931 	struct buf *bp;
5932 	daddr_t bn;
5933 	size_t done_len = 0, cur_len = 0;
5934 	int err = 0;
5935 	int contig = 0;
5936 	int dolock;
5937 	int vmpss = 0;
5938 	struct ulockfs *ulp;
5939 
5940 	if ((flags & B_READ) && pp != NULL && pp->p_vnode == vp &&
5941 	    vp->v_mpssdata != NULL) {
5942 		vmpss = 1;
5943 	}
5944 
5945 	dolock = (rw_owner(&ip->i_contents) != curthread);
5946 	/*
5947 	 * We need a better check.  Ideally, we would use another
5948 	 * vnodeops so that hlocked and forcibly unmounted file
5949 	 * systems would return EIO where appropriate and w/o the
5950 	 * need for these checks.
5951 	 */
5952 	if ((ufsvfsp = ip->i_ufsvfs) == NULL)
5953 		return (EIO);
5954 
5955 	/*
5956 	 * For vmpss (pp can be NULL) case respect the quiesce protocol.
5957 	 * ul_lock must be taken before locking pages so we can't use it here
5958 	 * if pp is non NULL because segvn already locked pages
5959 	 * SE_EXCL. Instead we rely on the fact that a forced umount or
5960 	 * applying a filesystem lock via ufs_fiolfs() will block in the
5961 	 * implicit call to ufs_flush() until we unlock the pages after the
5962 	 * return to segvn. Other ufs_quiesce() callers keep ufs_quiesce_pend
5963 	 * above 0 until they are done. We have to be careful not to increment
5964 	 * ul_vnops_cnt here after forceful unmount hlocks the file system.
5965 	 *
5966 	 * If pp is NULL use ul_lock to make sure we don't increment
5967 	 * ul_vnops_cnt after forceful unmount hlocks the file system.
5968 	 */
5969 	if (vmpss || pp == NULL) {
5970 		ulp = &ufsvfsp->vfs_ulockfs;
5971 		if (pp == NULL)
5972 			mutex_enter(&ulp->ul_lock);
5973 		if (ulp->ul_fs_lock & ULOCKFS_GETREAD_MASK) {
5974 			if (pp == NULL) {
5975 				mutex_exit(&ulp->ul_lock);
5976 			}
5977 			return (vmpss ? EIO : EINVAL);
5978 		}
5979 		atomic_inc_ulong(&ulp->ul_vnops_cnt);
5980 		if (pp == NULL)
5981 			mutex_exit(&ulp->ul_lock);
5982 		if (ufs_quiesce_pend) {
5983 			if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
5984 				cv_broadcast(&ulp->ul_cv);
5985 			return (vmpss ? EIO : EINVAL);
5986 		}
5987 	}
5988 
5989 	if (dolock) {
5990 		/*
5991 		 * segvn may call VOP_PAGEIO() instead of VOP_GETPAGE() to
5992 		 * handle a fault against a segment that maps vnode pages with
5993 		 * large mappings.  Segvn creates pages and holds them locked
5994 		 * SE_EXCL during VOP_PAGEIO() call. In this case we have to
5995 		 * use rw_tryenter() to avoid a potential deadlock since in
5996 		 * lock order i_contents needs to be taken first.
5997 		 * Segvn will retry via VOP_GETPAGE() if VOP_PAGEIO() fails.
5998 		 */
5999 		if (!vmpss) {
6000 			rw_enter(&ip->i_contents, RW_READER);
6001 		} else if (!rw_tryenter(&ip->i_contents, RW_READER)) {
6002 			if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
6003 				cv_broadcast(&ulp->ul_cv);
6004 			return (EDEADLK);
6005 		}
6006 	}
6007 
6008 	/*
6009 	 * Return an error to segvn because the pagefault request is beyond
6010 	 * PAGESIZE rounded EOF.
6011 	 */
6012 	if (vmpss && btopr(io_off + io_len) > btopr(ip->i_size)) {
6013 		if (dolock)
6014 			rw_exit(&ip->i_contents);
6015 		if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
6016 			cv_broadcast(&ulp->ul_cv);
6017 		return (EFAULT);
6018 	}
6019 
6020 	if (pp == NULL) {
6021 		if (bmap_has_holes(ip)) {
6022 			err = ENOSYS;
6023 		} else {
6024 			err = EINVAL;
6025 		}
6026 		if (dolock)
6027 			rw_exit(&ip->i_contents);
6028 		if (!atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
6029 			cv_broadcast(&ulp->ul_cv);
6030 		return (err);
6031 	}
6032 
6033 	/*
6034 	 * Break the io request into chunks, one for each contiguous
6035 	 * stretch of disk blocks in the target file.
6036 	 */
6037 	while (done_len < io_len) {
6038 		ASSERT(cpp);
6039 		contig = 0;
6040 		if (err = bmap_read(ip, (u_offset_t)(io_off + done_len),
6041 		    &bn, &contig))
6042 			break;
6043 
6044 		if (bn == UFS_HOLE) {	/* No holey swapfiles */
6045 			if (vmpss) {
6046 				err = EFAULT;
6047 				break;
6048 			}
6049 			err = ufs_fault(ITOV(ip), "ufs_pageio: bn == UFS_HOLE");
6050 			break;
6051 		}
6052 
6053 		cur_len = MIN(io_len - done_len, contig);
6054 		/*
6055 		 * Zero out a page beyond EOF, when the last block of
6056 		 * a file is a UFS fragment so that ufs_pageio() can be used
6057 		 * instead of ufs_getpage() to handle faults against
6058 		 * segvn segments that use large pages.
6059 		 */
6060 		page_list_break(&cpp, &npp, btopr(cur_len));
6061 		if ((flags & B_READ) && (cur_len & PAGEOFFSET)) {
6062 			size_t xlen = cur_len & PAGEOFFSET;
6063 			pagezero(cpp->p_prev, xlen, PAGESIZE - xlen);
6064 		}
6065 
6066 		bp = pageio_setup(cpp, cur_len, ip->i_devvp, flags);
6067 		ASSERT(bp != NULL);
6068 
6069 		bp->b_edev = ip->i_dev;
6070 		bp->b_dev = cmpdev(ip->i_dev);
6071 		bp->b_blkno = bn;
6072 		bp->b_un.b_addr = (caddr_t)0;
6073 		bp->b_file = ip->i_vnode;
6074 
6075 		ufsvfsp->vfs_iotstamp = ddi_get_lbolt();
6076 		ub.ub_pageios.value.ul++;
6077 		if (ufsvfsp->vfs_snapshot)
6078 			fssnap_strategy(&(ufsvfsp->vfs_snapshot), bp);
6079 		else
6080 			(void) bdev_strategy(bp);
6081 
6082 		if (flags & B_READ)
6083 			ufs_pageio_reads++;
6084 		else
6085 			ufs_pageio_writes++;
6086 		if (flags & B_READ)
6087 			lwp_stat_update(LWP_STAT_INBLK, 1);
6088 		else
6089 			lwp_stat_update(LWP_STAT_OUBLK, 1);
6090 		/*
6091 		 * If the request is not B_ASYNC, wait for i/o to complete
6092 		 * and re-assemble the page list to return to the caller.
6093 		 * If it is B_ASYNC we leave the page list in pieces and
6094 		 * cleanup() will dispose of them.
6095 		 */
6096 		if ((flags & B_ASYNC) == 0) {
6097 			err = biowait(bp);
6098 			pageio_done(bp);
6099 			if (err)
6100 				break;
6101 			page_list_concat(&opp, &cpp);
6102 		}
6103 		cpp = npp;
6104 		npp = NULL;
6105 		if (flags & B_READ)
6106 			cur_len = P2ROUNDUP_TYPED(cur_len, PAGESIZE, size_t);
6107 		done_len += cur_len;
6108 	}
6109 	ASSERT(err || (cpp == NULL && npp == NULL && done_len == io_len));
6110 	if (err) {
6111 		if (flags & B_ASYNC) {
6112 			/* Cleanup unprocessed parts of list */
6113 			page_list_concat(&cpp, &npp);
6114 			if (flags & B_READ)
6115 				pvn_read_done(cpp, B_ERROR);
6116 			else
6117 				pvn_write_done(cpp, B_ERROR);
6118 		} else {
6119 			/* Re-assemble list and let caller clean up */
6120 			page_list_concat(&opp, &cpp);
6121 			page_list_concat(&opp, &npp);
6122 		}
6123 	}
6124 
6125 	if (vmpss && !(ip->i_flag & IACC) && !ULOCKFS_IS_NOIACC(ulp) &&
6126 	    ufsvfsp->vfs_fs->fs_ronly == 0 && !ufsvfsp->vfs_noatime) {
6127 		mutex_enter(&ip->i_tlock);
6128 		ip->i_flag |= IACC;
6129 		ITIMES_NOLOCK(ip);
6130 		mutex_exit(&ip->i_tlock);
6131 	}
6132 
6133 	if (dolock)
6134 		rw_exit(&ip->i_contents);
6135 	if (vmpss && !atomic_dec_ulong_nv(&ulp->ul_vnops_cnt))
6136 		cv_broadcast(&ulp->ul_cv);
6137 	return (err);
6138 }
6139 
6140 /*
6141  * Called when the kernel is in a frozen state to dump data
6142  * directly to the device. It uses a private dump data structure,
6143  * set up by dump_ctl, to locate the correct disk block to which to dump.
6144  */
6145 /*ARGSUSED*/
6146 static int
ufs_dump(vnode_t * vp,caddr_t addr,offset_t ldbn,offset_t dblks,caller_context_t * ct)6147 ufs_dump(vnode_t *vp, caddr_t addr, offset_t ldbn, offset_t dblks,
6148     caller_context_t *ct)
6149 {
6150 	u_offset_t	file_size;
6151 	struct inode    *ip = VTOI(vp);
6152 	struct fs	*fs = ip->i_fs;
6153 	daddr_t		dbn, lfsbn;
6154 	int		disk_blks = fs->fs_bsize >> DEV_BSHIFT;
6155 	int		error = 0;
6156 	int		ndbs, nfsbs;
6157 
6158 	/*
6159 	 * forced unmount case
6160 	 */
6161 	if (ip->i_ufsvfs == NULL)
6162 		return (EIO);
6163 	/*
6164 	 * Validate the inode that it has not been modified since
6165 	 * the dump structure is allocated.
6166 	 */
6167 	mutex_enter(&ip->i_tlock);
6168 	if ((dump_info == NULL) ||
6169 	    (dump_info->ip != ip) ||
6170 	    (dump_info->time.tv_sec != ip->i_mtime.tv_sec) ||
6171 	    (dump_info->time.tv_usec != ip->i_mtime.tv_usec)) {
6172 		mutex_exit(&ip->i_tlock);
6173 		return (-1);
6174 	}
6175 	mutex_exit(&ip->i_tlock);
6176 
6177 	/*
6178 	 * See that the file has room for this write
6179 	 */
6180 	UFS_GET_ISIZE(&file_size, ip);
6181 
6182 	if (ldbtob(ldbn + dblks) > file_size)
6183 		return (ENOSPC);
6184 
6185 	/*
6186 	 * Find the physical disk block numbers from the dump
6187 	 * private data structure directly and write out the data
6188 	 * in contiguous block lumps
6189 	 */
6190 	while (dblks > 0 && !error) {
6191 		lfsbn = (daddr_t)lblkno(fs, ldbtob(ldbn));
6192 		dbn = fsbtodb(fs, dump_info->dblk[lfsbn]) + ldbn % disk_blks;
6193 		nfsbs = 1;
6194 		ndbs = disk_blks - ldbn % disk_blks;
6195 		while (ndbs < dblks && fsbtodb(fs, dump_info->dblk[lfsbn +
6196 		    nfsbs]) == dbn + ndbs) {
6197 			nfsbs++;
6198 			ndbs += disk_blks;
6199 		}
6200 		if (ndbs > dblks)
6201 			ndbs = dblks;
6202 		error = bdev_dump(ip->i_dev, addr, dbn, ndbs);
6203 		addr += ldbtob((offset_t)ndbs);
6204 		dblks -= ndbs;
6205 		ldbn += ndbs;
6206 	}
6207 	return (error);
6208 
6209 }
6210 
6211 /*
6212  * Prepare the file system before and after the dump operation.
6213  *
6214  * action = DUMP_ALLOC:
6215  * Preparation before dump, allocate dump private data structure
6216  * to hold all the direct and indirect block info for dump.
6217  *
6218  * action = DUMP_FREE:
6219  * Clean up after dump, deallocate the dump private data structure.
6220  *
6221  * action = DUMP_SCAN:
6222  * Scan dump_info for *blkp DEV_BSIZE blocks of contig fs space;
6223  * if found, the starting file-relative DEV_BSIZE lbn is written
6224  * to *bklp; that lbn is intended for use with VOP_DUMP()
6225  */
6226 /*ARGSUSED*/
6227 static int
ufs_dumpctl(vnode_t * vp,int action,offset_t * blkp,caller_context_t * ct)6228 ufs_dumpctl(vnode_t *vp, int action, offset_t *blkp, caller_context_t *ct)
6229 {
6230 	struct inode	*ip = VTOI(vp);
6231 	ufsvfs_t	*ufsvfsp = ip->i_ufsvfs;
6232 	struct fs	*fs;
6233 	daddr32_t	*dblk, *storeblk;
6234 	daddr32_t	*nextblk, *endblk;
6235 	struct buf	*bp;
6236 	int		i, entry, entries;
6237 	int		n, ncontig;
6238 
6239 	/*
6240 	 * check for forced unmount
6241 	 */
6242 	if (ufsvfsp == NULL)
6243 		return (EIO);
6244 
6245 	if (action == DUMP_ALLOC) {
6246 		/*
6247 		 * alloc and record dump_info
6248 		 */
6249 		if (dump_info != NULL)
6250 			return (EINVAL);
6251 
6252 		ASSERT(vp->v_type == VREG);
6253 		fs = ufsvfsp->vfs_fs;
6254 
6255 		rw_enter(&ip->i_contents, RW_READER);
6256 
6257 		if (bmap_has_holes(ip)) {
6258 			rw_exit(&ip->i_contents);
6259 			return (EFAULT);
6260 		}
6261 
6262 		/*
6263 		 * calculate and allocate space needed according to i_size
6264 		 */
6265 		entries = (int)lblkno(fs, blkroundup(fs, ip->i_size));
6266 		dump_info = kmem_alloc(sizeof (struct dump) +
6267 		    (entries - 1) * sizeof (daddr32_t), KM_NOSLEEP);
6268 		if (dump_info == NULL) {
6269 			rw_exit(&ip->i_contents);
6270 			return (ENOMEM);
6271 		}
6272 
6273 		/* Start saving the info */
6274 		dump_info->fsbs = entries;
6275 		dump_info->ip = ip;
6276 		storeblk = &dump_info->dblk[0];
6277 
6278 		/* Direct Blocks */
6279 		for (entry = 0; entry < NDADDR && entry < entries; entry++)
6280 			*storeblk++ = ip->i_db[entry];
6281 
6282 		/* Indirect Blocks */
6283 		for (i = 0; i < NIADDR; i++) {
6284 			int error = 0;
6285 
6286 			bp = UFS_BREAD(ufsvfsp,
6287 			    ip->i_dev, fsbtodb(fs, ip->i_ib[i]), fs->fs_bsize);
6288 			if (bp->b_flags & B_ERROR)
6289 				error = EIO;
6290 			else {
6291 				dblk = bp->b_un.b_daddr;
6292 				if ((storeblk = save_dblks(ip, ufsvfsp,
6293 				    storeblk, dblk, i, entries)) == NULL)
6294 					error = EIO;
6295 			}
6296 
6297 			brelse(bp);
6298 
6299 			if (error != 0) {
6300 				kmem_free(dump_info, sizeof (struct dump) +
6301 				    (entries - 1) * sizeof (daddr32_t));
6302 				rw_exit(&ip->i_contents);
6303 				dump_info = NULL;
6304 				return (error);
6305 			}
6306 		}
6307 		/* and time stamp the information */
6308 		mutex_enter(&ip->i_tlock);
6309 		dump_info->time = ip->i_mtime;
6310 		mutex_exit(&ip->i_tlock);
6311 
6312 		rw_exit(&ip->i_contents);
6313 	} else if (action == DUMP_FREE) {
6314 		/*
6315 		 * free dump_info
6316 		 */
6317 		if (dump_info == NULL)
6318 			return (EINVAL);
6319 		entries = dump_info->fsbs - 1;
6320 		kmem_free(dump_info, sizeof (struct dump) +
6321 		    entries * sizeof (daddr32_t));
6322 		dump_info = NULL;
6323 	} else if (action == DUMP_SCAN) {
6324 		/*
6325 		 * scan dump_info
6326 		 */
6327 		if (dump_info == NULL)
6328 			return (EINVAL);
6329 
6330 		dblk = dump_info->dblk;
6331 		nextblk = dblk + 1;
6332 		endblk = dblk + dump_info->fsbs - 1;
6333 		fs = ufsvfsp->vfs_fs;
6334 		ncontig = *blkp >> (fs->fs_bshift - DEV_BSHIFT);
6335 
6336 		/*
6337 		 * scan dblk[] entries; contig fs space is found when:
6338 		 * ((current blkno + frags per block) == next blkno)
6339 		 */
6340 		n = 0;
6341 		while (n < ncontig && dblk < endblk) {
6342 			if ((*dblk + fs->fs_frag) == *nextblk)
6343 				n++;
6344 			else
6345 				n = 0;
6346 			dblk++;
6347 			nextblk++;
6348 		}
6349 
6350 		/*
6351 		 * index is where size bytes of contig space begins;
6352 		 * conversion from index to the file's DEV_BSIZE lbn
6353 		 * is equivalent to:  (index * fs_bsize) / DEV_BSIZE
6354 		 */
6355 		if (n == ncontig) {
6356 			i = (dblk - dump_info->dblk) - ncontig;
6357 			*blkp = i << (fs->fs_bshift - DEV_BSHIFT);
6358 		} else
6359 			return (EFAULT);
6360 	}
6361 	return (0);
6362 }
6363 
6364 /*
6365  * Recursive helper function for ufs_dumpctl().  It follows the indirect file
6366  * system  blocks until it reaches the the disk block addresses, which are
6367  * then stored into the given buffer, storeblk.
6368  */
6369 static daddr32_t *
save_dblks(struct inode * ip,struct ufsvfs * ufsvfsp,daddr32_t * storeblk,daddr32_t * dblk,int level,int entries)6370 save_dblks(struct inode *ip, struct ufsvfs *ufsvfsp,  daddr32_t *storeblk,
6371     daddr32_t *dblk, int level, int entries)
6372 {
6373 	struct fs	*fs = ufsvfsp->vfs_fs;
6374 	struct buf	*bp;
6375 	int		i;
6376 
6377 	if (level == 0) {
6378 		for (i = 0; i < NINDIR(fs); i++) {
6379 			if (storeblk - dump_info->dblk >= entries)
6380 				break;
6381 			*storeblk++ = dblk[i];
6382 		}
6383 		return (storeblk);
6384 	}
6385 	for (i = 0; i < NINDIR(fs); i++) {
6386 		if (storeblk - dump_info->dblk >= entries)
6387 			break;
6388 		bp = UFS_BREAD(ufsvfsp,
6389 		    ip->i_dev, fsbtodb(fs, dblk[i]), fs->fs_bsize);
6390 		if (bp->b_flags & B_ERROR) {
6391 			brelse(bp);
6392 			return (NULL);
6393 		}
6394 		storeblk = save_dblks(ip, ufsvfsp, storeblk, bp->b_un.b_daddr,
6395 		    level - 1, entries);
6396 		brelse(bp);
6397 
6398 		if (storeblk == NULL)
6399 			return (NULL);
6400 	}
6401 	return (storeblk);
6402 }
6403 
6404 /* ARGSUSED */
6405 static int
ufs_getsecattr(struct vnode * vp,vsecattr_t * vsap,int flag,struct cred * cr,caller_context_t * ct)6406 ufs_getsecattr(struct vnode *vp, vsecattr_t *vsap, int flag,
6407 	struct cred *cr, caller_context_t *ct)
6408 {
6409 	struct inode	*ip = VTOI(vp);
6410 	struct ulockfs	*ulp;
6411 	struct ufsvfs	*ufsvfsp = ip->i_ufsvfs;
6412 	ulong_t		vsa_mask = vsap->vsa_mask;
6413 	int		err = EINVAL;
6414 
6415 	vsa_mask &= (VSA_ACL | VSA_ACLCNT | VSA_DFACL | VSA_DFACLCNT);
6416 
6417 	/*
6418 	 * Only grab locks if needed - they're not needed to check vsa_mask
6419 	 * or if the mask contains no acl flags.
6420 	 */
6421 	if (vsa_mask != 0) {
6422 		if (err = ufs_lockfs_begin(ufsvfsp, &ulp,
6423 		    ULOCKFS_GETATTR_MASK))
6424 			return (err);
6425 
6426 		rw_enter(&ip->i_contents, RW_READER);
6427 		err = ufs_acl_get(ip, vsap, flag, cr);
6428 		rw_exit(&ip->i_contents);
6429 
6430 		if (ulp)
6431 			ufs_lockfs_end(ulp);
6432 	}
6433 	return (err);
6434 }
6435 
6436 /* ARGSUSED */
6437 static int
ufs_setsecattr(struct vnode * vp,vsecattr_t * vsap,int flag,struct cred * cr,caller_context_t * ct)6438 ufs_setsecattr(struct vnode *vp, vsecattr_t *vsap, int flag, struct cred *cr,
6439 	caller_context_t *ct)
6440 {
6441 	struct inode	*ip = VTOI(vp);
6442 	struct ulockfs	*ulp = NULL;
6443 	struct ufsvfs	*ufsvfsp = VTOI(vp)->i_ufsvfs;
6444 	ulong_t		vsa_mask = vsap->vsa_mask;
6445 	int		err;
6446 	int		haverwlock = 1;
6447 	int		trans_size;
6448 	int		donetrans = 0;
6449 	int		retry = 1;
6450 
6451 	ASSERT(RW_LOCK_HELD(&ip->i_rwlock));
6452 
6453 	/* Abort now if the request is either empty or invalid. */
6454 	vsa_mask &= (VSA_ACL | VSA_ACLCNT | VSA_DFACL | VSA_DFACLCNT);
6455 	if ((vsa_mask == 0) ||
6456 	    ((vsap->vsa_aclentp == NULL) &&
6457 	    (vsap->vsa_dfaclentp == NULL))) {
6458 		err = EINVAL;
6459 		goto out;
6460 	}
6461 
6462 	/*
6463 	 * Following convention, if this is a directory then we acquire the
6464 	 * inode's i_rwlock after starting a UFS logging transaction;
6465 	 * otherwise, we acquire it beforehand. Since we were called (and
6466 	 * must therefore return) with the lock held, we will have to drop it,
6467 	 * and later reacquire it, if operating on a directory.
6468 	 */
6469 	if (vp->v_type == VDIR) {
6470 		rw_exit(&ip->i_rwlock);
6471 		haverwlock = 0;
6472 	} else {
6473 		/* Upgrade the lock if required. */
6474 		if (!rw_write_held(&ip->i_rwlock)) {
6475 			rw_exit(&ip->i_rwlock);
6476 			rw_enter(&ip->i_rwlock, RW_WRITER);
6477 		}
6478 	}
6479 
6480 again:
6481 	ASSERT(!(vp->v_type == VDIR && haverwlock));
6482 	if (err = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_SETATTR_MASK)) {
6483 		ulp = NULL;
6484 		retry = 0;
6485 		goto out;
6486 	}
6487 
6488 	/*
6489 	 * Check that the file system supports this operation. Note that
6490 	 * ufs_lockfs_begin() will have checked that the file system had
6491 	 * not been forcibly unmounted.
6492 	 */
6493 	if (ufsvfsp->vfs_fs->fs_ronly) {
6494 		err = EROFS;
6495 		goto out;
6496 	}
6497 	if (ufsvfsp->vfs_nosetsec) {
6498 		err = ENOSYS;
6499 		goto out;
6500 	}
6501 
6502 	if (ulp) {
6503 		TRANS_BEGIN_ASYNC(ufsvfsp, TOP_SETSECATTR,
6504 		    trans_size = TOP_SETSECATTR_SIZE(VTOI(vp)));
6505 		donetrans = 1;
6506 	}
6507 
6508 	if (vp->v_type == VDIR) {
6509 		rw_enter(&ip->i_rwlock, RW_WRITER);
6510 		haverwlock = 1;
6511 	}
6512 
6513 	ASSERT(haverwlock);
6514 
6515 	/* Do the actual work. */
6516 	rw_enter(&ip->i_contents, RW_WRITER);
6517 	/*
6518 	 * Suppress out of inodes messages if we will retry.
6519 	 */
6520 	if (retry)
6521 		ip->i_flag |= IQUIET;
6522 	err = ufs_acl_set(ip, vsap, flag, cr);
6523 	ip->i_flag &= ~IQUIET;
6524 	rw_exit(&ip->i_contents);
6525 
6526 out:
6527 	if (ulp) {
6528 		if (donetrans) {
6529 			/*
6530 			 * top_end_async() can eventually call
6531 			 * top_end_sync(), which can block. We must
6532 			 * therefore observe the lock-ordering protocol
6533 			 * here as well.
6534 			 */
6535 			if (vp->v_type == VDIR) {
6536 				rw_exit(&ip->i_rwlock);
6537 				haverwlock = 0;
6538 			}
6539 			TRANS_END_ASYNC(ufsvfsp, TOP_SETSECATTR, trans_size);
6540 		}
6541 		ufs_lockfs_end(ulp);
6542 	}
6543 	/*
6544 	 * If no inodes available, try scaring a logically-
6545 	 * free one out of the delete queue to someplace
6546 	 * that we can find it.
6547 	 */
6548 	if ((err == ENOSPC) && retry && TRANS_ISTRANS(ufsvfsp)) {
6549 		ufs_delete_drain_wait(ufsvfsp, 1);
6550 		retry = 0;
6551 		if (vp->v_type == VDIR && haverwlock) {
6552 			rw_exit(&ip->i_rwlock);
6553 			haverwlock = 0;
6554 		}
6555 		goto again;
6556 	}
6557 	/*
6558 	 * If we need to reacquire the lock then it is safe to do so
6559 	 * as a reader. This is because ufs_rwunlock(), which will be
6560 	 * called by our caller after we return, does not differentiate
6561 	 * between shared and exclusive locks.
6562 	 */
6563 	if (!haverwlock) {
6564 		ASSERT(vp->v_type == VDIR);
6565 		rw_enter(&ip->i_rwlock, RW_READER);
6566 	}
6567 
6568 	return (err);
6569 }
6570 
6571 /*
6572  * Locate the vnode to be used for an event notification. As this will
6573  * be called prior to the name space change perform basic verification
6574  * that the change will be allowed.
6575  */
6576 
6577 static int
ufs_eventlookup(struct vnode * dvp,char * nm,struct cred * cr,struct vnode ** vpp)6578 ufs_eventlookup(struct vnode *dvp, char *nm, struct cred *cr,
6579     struct vnode **vpp)
6580 {
6581 	int	namlen;
6582 	int	error;
6583 	struct vnode	*vp;
6584 	struct inode	*ip;
6585 	struct inode	*xip;
6586 	struct ufsvfs	*ufsvfsp;
6587 	struct ulockfs	*ulp;
6588 
6589 	ip = VTOI(dvp);
6590 	*vpp = NULL;
6591 
6592 	if ((namlen = strlen(nm)) == 0)
6593 		return (EINVAL);
6594 
6595 	if (nm[0] == '.') {
6596 		if (namlen == 1)
6597 			return (EINVAL);
6598 		else if ((namlen == 2) && nm[1] == '.') {
6599 			return (EEXIST);
6600 		}
6601 	}
6602 
6603 	/*
6604 	 * Check accessibility and write access of parent directory as we
6605 	 * only want to post the event if we're able to make a change.
6606 	 */
6607 	if (error = ufs_diraccess(ip, IEXEC|IWRITE, cr))
6608 		return (error);
6609 
6610 	if (vp = dnlc_lookup(dvp, nm)) {
6611 		if (vp == DNLC_NO_VNODE) {
6612 			VN_RELE(vp);
6613 			return (ENOENT);
6614 		}
6615 
6616 		*vpp = vp;
6617 		return (0);
6618 	}
6619 
6620 	/*
6621 	 * Keep the idle queue from getting too long by idling two
6622 	 * inodes before attempting to allocate another.
6623 	 * This operation must be performed before entering lockfs
6624 	 * or a transaction.
6625 	 */
6626 	if (ufs_idle_q.uq_ne > ufs_idle_q.uq_hiwat)
6627 		if ((curthread->t_flag & T_DONTBLOCK) == 0) {
6628 			ins.in_lidles.value.ul += ufs_lookup_idle_count;
6629 			ufs_idle_some(ufs_lookup_idle_count);
6630 		}
6631 
6632 	ufsvfsp = ip->i_ufsvfs;
6633 
6634 retry_lookup:
6635 	if (error = ufs_lockfs_begin(ufsvfsp, &ulp, ULOCKFS_LOOKUP_MASK))
6636 		return (error);
6637 
6638 	if ((error = ufs_dirlook(ip, nm, &xip, cr, 1, 1)) == 0) {
6639 		vp = ITOV(xip);
6640 		*vpp = vp;
6641 	}
6642 
6643 	if (ulp) {
6644 		ufs_lockfs_end(ulp);
6645 	}
6646 
6647 	if (error == EAGAIN)
6648 		goto retry_lookup;
6649 
6650 	return (error);
6651 }
6652