xref: /titanic_50/usr/src/uts/common/fs/vnode.c (revision dfb96a4f56fb431b915bc67e5d9d5c8d4f4f6679)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*	Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T	*/
27 /*	  All Rights Reserved  	*/
28 
29 /*
30  * University Copyright- Copyright (c) 1982, 1986, 1988
31  * The Regents of the University of California
32  * All Rights Reserved
33  *
34  * University Acknowledgment- Portions of this document are derived from
35  * software developed by the University of California, Berkeley, and its
36  * contributors.
37  */
38 
39 
40 #pragma ident	"%Z%%M%	%I%	%E% SMI"
41 
42 #include <sys/types.h>
43 #include <sys/param.h>
44 #include <sys/t_lock.h>
45 #include <sys/errno.h>
46 #include <sys/cred.h>
47 #include <sys/user.h>
48 #include <sys/uio.h>
49 #include <sys/file.h>
50 #include <sys/pathname.h>
51 #include <sys/vfs.h>
52 #include <sys/vfs_opreg.h>
53 #include <sys/vnode.h>
54 #include <sys/rwstlock.h>
55 #include <sys/fem.h>
56 #include <sys/stat.h>
57 #include <sys/mode.h>
58 #include <sys/conf.h>
59 #include <sys/sysmacros.h>
60 #include <sys/cmn_err.h>
61 #include <sys/systm.h>
62 #include <sys/kmem.h>
63 #include <sys/debug.h>
64 #include <c2/audit.h>
65 #include <sys/acl.h>
66 #include <sys/nbmlock.h>
67 #include <sys/fcntl.h>
68 #include <fs/fs_subr.h>
69 
70 /* Determine if this vnode is a file that is read-only */
71 #define	ISROFILE(vp)	\
72 	((vp)->v_type != VCHR && (vp)->v_type != VBLK && \
73 	    (vp)->v_type != VFIFO && vn_is_readonly(vp))
74 
75 /* Tunable via /etc/system; used only by admin/install */
76 int nfs_global_client_only;
77 
78 /*
79  * Array of vopstats_t for per-FS-type vopstats.  This array has the same
80  * number of entries as and parallel to the vfssw table.  (Arguably, it could
81  * be part of the vfssw table.)  Once it's initialized, it's accessed using
82  * the same fstype index that is used to index into the vfssw table.
83  */
84 vopstats_t **vopstats_fstype;
85 
86 /* vopstats initialization template used for fast initialization via bcopy() */
87 static vopstats_t *vs_templatep;
88 
89 /* Kmem cache handle for vsk_anchor_t allocations */
90 kmem_cache_t *vsk_anchor_cache;
91 
92 /*
93  * Root of AVL tree for the kstats associated with vopstats.  Lock protects
94  * updates to vsktat_tree.
95  */
96 avl_tree_t	vskstat_tree;
97 kmutex_t	vskstat_tree_lock;
98 
99 /* Global variable which enables/disables the vopstats collection */
100 int vopstats_enabled = 1;
101 
102 /*
103  * The following is the common set of actions needed to update the
104  * vopstats structure from a vnode op.  Both VOPSTATS_UPDATE() and
105  * VOPSTATS_UPDATE_IO() do almost the same thing, except for the
106  * recording of the bytes transferred.  Since the code is similar
107  * but small, it is nearly a duplicate.  Consequently any changes
108  * to one may need to be reflected in the other.
109  * Rundown of the variables:
110  * vp - Pointer to the vnode
111  * counter - Partial name structure member to update in vopstats for counts
112  * bytecounter - Partial name structure member to update in vopstats for bytes
113  * bytesval - Value to update in vopstats for bytes
114  * fstype - Index into vsanchor_fstype[], same as index into vfssw[]
115  * vsp - Pointer to vopstats structure (either in vfs or vsanchor_fstype[i])
116  */
117 
118 #define	VOPSTATS_UPDATE(vp, counter) {					\
119 	vfs_t *vfsp = (vp)->v_vfsp;					\
120 	if (vfsp && vfsp->vfs_implp &&					\
121 	    (vfsp->vfs_flag & VFS_STATS) && (vp)->v_type != VBAD) {	\
122 		vopstats_t *vsp = &vfsp->vfs_vopstats;			\
123 		uint64_t *stataddr = &(vsp->n##counter.value.ui64);	\
124 		extern void __dtrace_probe___fsinfo_##counter(vnode_t *, \
125 		    size_t, uint64_t *);				\
126 		__dtrace_probe___fsinfo_##counter(vp, 0, stataddr);	\
127 		(*stataddr)++;						\
128 		if ((vsp = vfsp->vfs_fstypevsp) != NULL) {		\
129 			vsp->n##counter.value.ui64++;			\
130 		}							\
131 	}								\
132 }
133 
134 #define	VOPSTATS_UPDATE_IO(vp, counter, bytecounter, bytesval) {	\
135 	vfs_t *vfsp = (vp)->v_vfsp;					\
136 	if (vfsp && vfsp->vfs_implp &&					\
137 	    (vfsp->vfs_flag & VFS_STATS) && (vp)->v_type != VBAD) {	\
138 		vopstats_t *vsp = &vfsp->vfs_vopstats;			\
139 		uint64_t *stataddr = &(vsp->n##counter.value.ui64);	\
140 		extern void __dtrace_probe___fsinfo_##counter(vnode_t *, \
141 		    size_t, uint64_t *);				\
142 		__dtrace_probe___fsinfo_##counter(vp, bytesval, stataddr); \
143 		(*stataddr)++;						\
144 		vsp->bytecounter.value.ui64 += bytesval;		\
145 		if ((vsp = vfsp->vfs_fstypevsp) != NULL) {		\
146 			vsp->n##counter.value.ui64++;			\
147 			vsp->bytecounter.value.ui64 += bytesval;	\
148 		}							\
149 	}								\
150 }
151 
152 /*
153  * Convert stat(2) formats to vnode types and vice versa.  (Knows about
154  * numerical order of S_IFMT and vnode types.)
155  */
156 enum vtype iftovt_tab[] = {
157 	VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
158 	VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON
159 };
160 
161 ushort_t vttoif_tab[] = {
162 	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFIFO,
163 	S_IFDOOR, 0, S_IFSOCK, S_IFPORT, 0
164 };
165 
166 /*
167  * The system vnode cache.
168  */
169 
170 kmem_cache_t *vn_cache;
171 
172 
173 /*
174  * Vnode operations vector.
175  */
176 
177 static const fs_operation_trans_def_t vn_ops_table[] = {
178 	VOPNAME_OPEN, offsetof(struct vnodeops, vop_open),
179 	    fs_nosys, fs_nosys,
180 
181 	VOPNAME_CLOSE, offsetof(struct vnodeops, vop_close),
182 	    fs_nosys, fs_nosys,
183 
184 	VOPNAME_READ, offsetof(struct vnodeops, vop_read),
185 	    fs_nosys, fs_nosys,
186 
187 	VOPNAME_WRITE, offsetof(struct vnodeops, vop_write),
188 	    fs_nosys, fs_nosys,
189 
190 	VOPNAME_IOCTL, offsetof(struct vnodeops, vop_ioctl),
191 	    fs_nosys, fs_nosys,
192 
193 	VOPNAME_SETFL, offsetof(struct vnodeops, vop_setfl),
194 	    fs_setfl, fs_nosys,
195 
196 	VOPNAME_GETATTR, offsetof(struct vnodeops, vop_getattr),
197 	    fs_nosys, fs_nosys,
198 
199 	VOPNAME_SETATTR, offsetof(struct vnodeops, vop_setattr),
200 	    fs_nosys, fs_nosys,
201 
202 	VOPNAME_ACCESS, offsetof(struct vnodeops, vop_access),
203 	    fs_nosys, fs_nosys,
204 
205 	VOPNAME_LOOKUP, offsetof(struct vnodeops, vop_lookup),
206 	    fs_nosys, fs_nosys,
207 
208 	VOPNAME_CREATE, offsetof(struct vnodeops, vop_create),
209 	    fs_nosys, fs_nosys,
210 
211 	VOPNAME_REMOVE, offsetof(struct vnodeops, vop_remove),
212 	    fs_nosys, fs_nosys,
213 
214 	VOPNAME_LINK, offsetof(struct vnodeops, vop_link),
215 	    fs_nosys, fs_nosys,
216 
217 	VOPNAME_RENAME, offsetof(struct vnodeops, vop_rename),
218 	    fs_nosys, fs_nosys,
219 
220 	VOPNAME_MKDIR, offsetof(struct vnodeops, vop_mkdir),
221 	    fs_nosys, fs_nosys,
222 
223 	VOPNAME_RMDIR, offsetof(struct vnodeops, vop_rmdir),
224 	    fs_nosys, fs_nosys,
225 
226 	VOPNAME_READDIR, offsetof(struct vnodeops, vop_readdir),
227 	    fs_nosys, fs_nosys,
228 
229 	VOPNAME_SYMLINK, offsetof(struct vnodeops, vop_symlink),
230 	    fs_nosys, fs_nosys,
231 
232 	VOPNAME_READLINK, offsetof(struct vnodeops, vop_readlink),
233 	    fs_nosys, fs_nosys,
234 
235 	VOPNAME_FSYNC, offsetof(struct vnodeops, vop_fsync),
236 	    fs_nosys, fs_nosys,
237 
238 	VOPNAME_INACTIVE, offsetof(struct vnodeops, vop_inactive),
239 	    fs_nosys, fs_nosys,
240 
241 	VOPNAME_FID, offsetof(struct vnodeops, vop_fid),
242 	    fs_nosys, fs_nosys,
243 
244 	VOPNAME_RWLOCK, offsetof(struct vnodeops, vop_rwlock),
245 	    fs_rwlock, fs_rwlock,
246 
247 	VOPNAME_RWUNLOCK, offsetof(struct vnodeops, vop_rwunlock),
248 	    (fs_generic_func_p) fs_rwunlock,
249 	    (fs_generic_func_p) fs_rwunlock,	/* no errors allowed */
250 
251 	VOPNAME_SEEK, offsetof(struct vnodeops, vop_seek),
252 	    fs_nosys, fs_nosys,
253 
254 	VOPNAME_CMP, offsetof(struct vnodeops, vop_cmp),
255 	    fs_cmp, fs_cmp,		/* no errors allowed */
256 
257 	VOPNAME_FRLOCK, offsetof(struct vnodeops, vop_frlock),
258 	    fs_frlock, fs_nosys,
259 
260 	VOPNAME_SPACE, offsetof(struct vnodeops, vop_space),
261 	    fs_nosys, fs_nosys,
262 
263 	VOPNAME_REALVP, offsetof(struct vnodeops, vop_realvp),
264 	    fs_nosys, fs_nosys,
265 
266 	VOPNAME_GETPAGE, offsetof(struct vnodeops, vop_getpage),
267 	    fs_nosys, fs_nosys,
268 
269 	VOPNAME_PUTPAGE, offsetof(struct vnodeops, vop_putpage),
270 	    fs_nosys, fs_nosys,
271 
272 	VOPNAME_MAP, offsetof(struct vnodeops, vop_map),
273 	    (fs_generic_func_p) fs_nosys_map,
274 	    (fs_generic_func_p) fs_nosys_map,
275 
276 	VOPNAME_ADDMAP, offsetof(struct vnodeops, vop_addmap),
277 	    (fs_generic_func_p) fs_nosys_addmap,
278 	    (fs_generic_func_p) fs_nosys_addmap,
279 
280 	VOPNAME_DELMAP, offsetof(struct vnodeops, vop_delmap),
281 	    fs_nosys, fs_nosys,
282 
283 	VOPNAME_POLL, offsetof(struct vnodeops, vop_poll),
284 	    (fs_generic_func_p) fs_poll, (fs_generic_func_p) fs_nosys_poll,
285 
286 	VOPNAME_DUMP, offsetof(struct vnodeops, vop_dump),
287 	    fs_nosys, fs_nosys,
288 
289 	VOPNAME_PATHCONF, offsetof(struct vnodeops, vop_pathconf),
290 	    fs_pathconf, fs_nosys,
291 
292 	VOPNAME_PAGEIO, offsetof(struct vnodeops, vop_pageio),
293 	    fs_nosys, fs_nosys,
294 
295 	VOPNAME_DUMPCTL, offsetof(struct vnodeops, vop_dumpctl),
296 	    fs_nosys, fs_nosys,
297 
298 	VOPNAME_DISPOSE, offsetof(struct vnodeops, vop_dispose),
299 	    (fs_generic_func_p) fs_dispose,
300 	    (fs_generic_func_p) fs_nodispose,
301 
302 	VOPNAME_SETSECATTR, offsetof(struct vnodeops, vop_setsecattr),
303 	    fs_nosys, fs_nosys,
304 
305 	VOPNAME_GETSECATTR, offsetof(struct vnodeops, vop_getsecattr),
306 	    fs_fab_acl, fs_nosys,
307 
308 	VOPNAME_SHRLOCK, offsetof(struct vnodeops, vop_shrlock),
309 	    fs_shrlock, fs_nosys,
310 
311 	VOPNAME_VNEVENT, offsetof(struct vnodeops, vop_vnevent),
312 	    (fs_generic_func_p) fs_vnevent_nosupport,
313 	    (fs_generic_func_p) fs_vnevent_nosupport,
314 
315 	NULL, 0, NULL, NULL
316 };
317 
318 /*
319  * Used by the AVL routines to compare two vsk_anchor_t structures in the tree.
320  * We use the f_fsid reported by VFS_STATVFS() since we use that for the
321  * kstat name.
322  */
323 static int
324 vska_compar(const void *n1, const void *n2)
325 {
326 	int ret;
327 	ulong_t p1 = ((vsk_anchor_t *)n1)->vsk_fsid;
328 	ulong_t p2 = ((vsk_anchor_t *)n2)->vsk_fsid;
329 
330 	if (p1 < p2) {
331 		ret = -1;
332 	} else if (p1 > p2) {
333 		ret = 1;
334 	} else {
335 		ret = 0;
336 	}
337 
338 	return (ret);
339 }
340 
341 /*
342  * Used to create a single template which will be bcopy()ed to a newly
343  * allocated vsanchor_combo_t structure in new_vsanchor(), below.
344  */
345 static vopstats_t *
346 create_vopstats_template()
347 {
348 	vopstats_t		*vsp;
349 
350 	vsp = kmem_alloc(sizeof (vopstats_t), KM_SLEEP);
351 	bzero(vsp, sizeof (*vsp));	/* Start fresh */
352 
353 	/* VOP_OPEN */
354 	kstat_named_init(&vsp->nopen, "nopen", KSTAT_DATA_UINT64);
355 	/* VOP_CLOSE */
356 	kstat_named_init(&vsp->nclose, "nclose", KSTAT_DATA_UINT64);
357 	/* VOP_READ I/O */
358 	kstat_named_init(&vsp->nread, "nread", KSTAT_DATA_UINT64);
359 	kstat_named_init(&vsp->read_bytes, "read_bytes", KSTAT_DATA_UINT64);
360 	/* VOP_WRITE I/O */
361 	kstat_named_init(&vsp->nwrite, "nwrite", KSTAT_DATA_UINT64);
362 	kstat_named_init(&vsp->write_bytes, "write_bytes", KSTAT_DATA_UINT64);
363 	/* VOP_IOCTL */
364 	kstat_named_init(&vsp->nioctl, "nioctl", KSTAT_DATA_UINT64);
365 	/* VOP_SETFL */
366 	kstat_named_init(&vsp->nsetfl, "nsetfl", KSTAT_DATA_UINT64);
367 	/* VOP_GETATTR */
368 	kstat_named_init(&vsp->ngetattr, "ngetattr", KSTAT_DATA_UINT64);
369 	/* VOP_SETATTR */
370 	kstat_named_init(&vsp->nsetattr, "nsetattr", KSTAT_DATA_UINT64);
371 	/* VOP_ACCESS */
372 	kstat_named_init(&vsp->naccess, "naccess", KSTAT_DATA_UINT64);
373 	/* VOP_LOOKUP */
374 	kstat_named_init(&vsp->nlookup, "nlookup", KSTAT_DATA_UINT64);
375 	/* VOP_CREATE */
376 	kstat_named_init(&vsp->ncreate, "ncreate", KSTAT_DATA_UINT64);
377 	/* VOP_REMOVE */
378 	kstat_named_init(&vsp->nremove, "nremove", KSTAT_DATA_UINT64);
379 	/* VOP_LINK */
380 	kstat_named_init(&vsp->nlink, "nlink", KSTAT_DATA_UINT64);
381 	/* VOP_RENAME */
382 	kstat_named_init(&vsp->nrename, "nrename", KSTAT_DATA_UINT64);
383 	/* VOP_MKDIR */
384 	kstat_named_init(&vsp->nmkdir, "nmkdir", KSTAT_DATA_UINT64);
385 	/* VOP_RMDIR */
386 	kstat_named_init(&vsp->nrmdir, "nrmdir", KSTAT_DATA_UINT64);
387 	/* VOP_READDIR I/O */
388 	kstat_named_init(&vsp->nreaddir, "nreaddir", KSTAT_DATA_UINT64);
389 	kstat_named_init(&vsp->readdir_bytes, "readdir_bytes",
390 	    KSTAT_DATA_UINT64);
391 	/* VOP_SYMLINK */
392 	kstat_named_init(&vsp->nsymlink, "nsymlink", KSTAT_DATA_UINT64);
393 	/* VOP_READLINK */
394 	kstat_named_init(&vsp->nreadlink, "nreadlink", KSTAT_DATA_UINT64);
395 	/* VOP_FSYNC */
396 	kstat_named_init(&vsp->nfsync, "nfsync", KSTAT_DATA_UINT64);
397 	/* VOP_INACTIVE */
398 	kstat_named_init(&vsp->ninactive, "ninactive", KSTAT_DATA_UINT64);
399 	/* VOP_FID */
400 	kstat_named_init(&vsp->nfid, "nfid", KSTAT_DATA_UINT64);
401 	/* VOP_RWLOCK */
402 	kstat_named_init(&vsp->nrwlock, "nrwlock", KSTAT_DATA_UINT64);
403 	/* VOP_RWUNLOCK */
404 	kstat_named_init(&vsp->nrwunlock, "nrwunlock", KSTAT_DATA_UINT64);
405 	/* VOP_SEEK */
406 	kstat_named_init(&vsp->nseek, "nseek", KSTAT_DATA_UINT64);
407 	/* VOP_CMP */
408 	kstat_named_init(&vsp->ncmp, "ncmp", KSTAT_DATA_UINT64);
409 	/* VOP_FRLOCK */
410 	kstat_named_init(&vsp->nfrlock, "nfrlock", KSTAT_DATA_UINT64);
411 	/* VOP_SPACE */
412 	kstat_named_init(&vsp->nspace, "nspace", KSTAT_DATA_UINT64);
413 	/* VOP_REALVP */
414 	kstat_named_init(&vsp->nrealvp, "nrealvp", KSTAT_DATA_UINT64);
415 	/* VOP_GETPAGE */
416 	kstat_named_init(&vsp->ngetpage, "ngetpage", KSTAT_DATA_UINT64);
417 	/* VOP_PUTPAGE */
418 	kstat_named_init(&vsp->nputpage, "nputpage", KSTAT_DATA_UINT64);
419 	/* VOP_MAP */
420 	kstat_named_init(&vsp->nmap, "nmap", KSTAT_DATA_UINT64);
421 	/* VOP_ADDMAP */
422 	kstat_named_init(&vsp->naddmap, "naddmap", KSTAT_DATA_UINT64);
423 	/* VOP_DELMAP */
424 	kstat_named_init(&vsp->ndelmap, "ndelmap", KSTAT_DATA_UINT64);
425 	/* VOP_POLL */
426 	kstat_named_init(&vsp->npoll, "npoll", KSTAT_DATA_UINT64);
427 	/* VOP_DUMP */
428 	kstat_named_init(&vsp->ndump, "ndump", KSTAT_DATA_UINT64);
429 	/* VOP_PATHCONF */
430 	kstat_named_init(&vsp->npathconf, "npathconf", KSTAT_DATA_UINT64);
431 	/* VOP_PAGEIO */
432 	kstat_named_init(&vsp->npageio, "npageio", KSTAT_DATA_UINT64);
433 	/* VOP_DUMPCTL */
434 	kstat_named_init(&vsp->ndumpctl, "ndumpctl", KSTAT_DATA_UINT64);
435 	/* VOP_DISPOSE */
436 	kstat_named_init(&vsp->ndispose, "ndispose", KSTAT_DATA_UINT64);
437 	/* VOP_SETSECATTR */
438 	kstat_named_init(&vsp->nsetsecattr, "nsetsecattr", KSTAT_DATA_UINT64);
439 	/* VOP_GETSECATTR */
440 	kstat_named_init(&vsp->ngetsecattr, "ngetsecattr", KSTAT_DATA_UINT64);
441 	/* VOP_SHRLOCK */
442 	kstat_named_init(&vsp->nshrlock, "nshrlock", KSTAT_DATA_UINT64);
443 	/* VOP_VNEVENT */
444 	kstat_named_init(&vsp->nvnevent, "nvnevent", KSTAT_DATA_UINT64);
445 
446 	return (vsp);
447 }
448 
449 /*
450  * Creates a kstat structure associated with a vopstats structure.
451  */
452 kstat_t *
453 new_vskstat(char *ksname, vopstats_t *vsp)
454 {
455 	kstat_t		*ksp;
456 
457 	if (!vopstats_enabled) {
458 		return (NULL);
459 	}
460 
461 	ksp = kstat_create("unix", 0, ksname, "misc", KSTAT_TYPE_NAMED,
462 	    sizeof (vopstats_t)/sizeof (kstat_named_t),
463 	    KSTAT_FLAG_VIRTUAL|KSTAT_FLAG_WRITABLE);
464 	if (ksp) {
465 		ksp->ks_data = vsp;
466 		kstat_install(ksp);
467 	}
468 
469 	return (ksp);
470 }
471 
472 /*
473  * Called from vfsinit() to initialize the support mechanisms for vopstats
474  */
475 void
476 vopstats_startup()
477 {
478 	if (!vopstats_enabled)
479 		return;
480 
481 	/*
482 	 * Creates the AVL tree which holds per-vfs vopstat anchors.  This
483 	 * is necessary since we need to check if a kstat exists before we
484 	 * attempt to create it.  Also, initialize its lock.
485 	 */
486 	avl_create(&vskstat_tree, vska_compar, sizeof (vsk_anchor_t),
487 	    offsetof(vsk_anchor_t, vsk_node));
488 	mutex_init(&vskstat_tree_lock, NULL, MUTEX_DEFAULT, NULL);
489 
490 	vsk_anchor_cache = kmem_cache_create("vsk_anchor_cache",
491 	    sizeof (vsk_anchor_t), sizeof (uintptr_t), NULL, NULL, NULL,
492 	    NULL, NULL, 0);
493 
494 	/*
495 	 * Set up the array of pointers for the vopstats-by-FS-type.
496 	 * The entries will be allocated/initialized as each file system
497 	 * goes through modload/mod_installfs.
498 	 */
499 	vopstats_fstype = (vopstats_t **)kmem_zalloc(
500 	    (sizeof (vopstats_t *) * nfstype), KM_SLEEP);
501 
502 	/* Set up the global vopstats initialization template */
503 	vs_templatep = create_vopstats_template();
504 }
505 
506 /*
507  * We need to have the all of the counters zeroed.
508  * The initialization of the vopstats_t includes on the order of
509  * 50 calls to kstat_named_init().  Rather that do that on every call,
510  * we do it once in a template (vs_templatep) then bcopy it over.
511  */
512 void
513 initialize_vopstats(vopstats_t *vsp)
514 {
515 	if (vsp == NULL)
516 		return;
517 
518 	bcopy(vs_templatep, vsp, sizeof (vopstats_t));
519 }
520 
521 /*
522  * If possible, determine which vopstats by fstype to use and
523  * return a pointer to the caller.
524  */
525 vopstats_t *
526 get_fstype_vopstats(vfs_t *vfsp, struct vfssw *vswp)
527 {
528 	int		fstype = 0;	/* Index into vfssw[] */
529 	vopstats_t	*vsp = NULL;
530 
531 	if (vfsp == NULL || (vfsp->vfs_flag & VFS_STATS) == 0 ||
532 	    !vopstats_enabled)
533 		return (NULL);
534 	/*
535 	 * Set up the fstype.  We go to so much trouble because all versions
536 	 * of NFS use the same fstype in their vfs even though they have
537 	 * distinct entries in the vfssw[] table.
538 	 * NOTE: A special vfs (e.g., EIO_vfs) may not have an entry.
539 	 */
540 	if (vswp) {
541 		fstype = vswp - vfssw;	/* Gets us the index */
542 	} else {
543 		fstype = vfsp->vfs_fstype;
544 	}
545 
546 	/*
547 	 * Point to the per-fstype vopstats. The only valid values are
548 	 * non-zero positive values less than the number of vfssw[] table
549 	 * entries.
550 	 */
551 	if (fstype > 0 && fstype < nfstype) {
552 		vsp = vopstats_fstype[fstype];
553 	}
554 
555 	return (vsp);
556 }
557 
558 /*
559  * Generate a kstat name, create the kstat structure, and allocate a
560  * vsk_anchor_t to hold it together.  Return the pointer to the vsk_anchor_t
561  * to the caller.  This must only be called from a mount.
562  */
563 vsk_anchor_t *
564 get_vskstat_anchor(vfs_t *vfsp)
565 {
566 	char		kstatstr[KSTAT_STRLEN]; /* kstat name for vopstats */
567 	statvfs64_t	statvfsbuf;		/* Needed to find f_fsid */
568 	vsk_anchor_t	*vskp = NULL;		/* vfs <--> kstat anchor */
569 	kstat_t		*ksp;			/* Ptr to new kstat */
570 	avl_index_t	where;			/* Location in the AVL tree */
571 
572 	if (vfsp == NULL || vfsp->vfs_implp == NULL ||
573 	    (vfsp->vfs_flag & VFS_STATS) == 0 || !vopstats_enabled)
574 		return (NULL);
575 
576 	/* Need to get the fsid to build a kstat name */
577 	if (VFS_STATVFS(vfsp, &statvfsbuf) == 0) {
578 		/* Create a name for our kstats based on fsid */
579 		(void) snprintf(kstatstr, KSTAT_STRLEN, "%s%lx",
580 		    VOPSTATS_STR, statvfsbuf.f_fsid);
581 
582 		/* Allocate and initialize the vsk_anchor_t */
583 		vskp = kmem_cache_alloc(vsk_anchor_cache, KM_SLEEP);
584 		bzero(vskp, sizeof (*vskp));
585 		vskp->vsk_fsid = statvfsbuf.f_fsid;
586 
587 		mutex_enter(&vskstat_tree_lock);
588 		if (avl_find(&vskstat_tree, vskp, &where) == NULL) {
589 			avl_insert(&vskstat_tree, vskp, where);
590 			mutex_exit(&vskstat_tree_lock);
591 
592 			/*
593 			 * Now that we've got the anchor in the AVL
594 			 * tree, we can create the kstat.
595 			 */
596 			ksp = new_vskstat(kstatstr, &vfsp->vfs_vopstats);
597 			if (ksp) {
598 				vskp->vsk_ksp = ksp;
599 			}
600 		} else {
601 			/* Oops, found one! Release memory and lock. */
602 			mutex_exit(&vskstat_tree_lock);
603 			kmem_cache_free(vsk_anchor_cache, vskp);
604 			vskp = NULL;
605 		}
606 	}
607 	return (vskp);
608 }
609 
610 /*
611  * We're in the process of tearing down the vfs and need to cleanup
612  * the data structures associated with the vopstats. Must only be called
613  * from dounmount().
614  */
615 void
616 teardown_vopstats(vfs_t *vfsp)
617 {
618 	vsk_anchor_t	*vskap;
619 	avl_index_t	where;
620 
621 	if (vfsp == NULL || vfsp->vfs_implp == NULL ||
622 	    (vfsp->vfs_flag & VFS_STATS) == 0 || !vopstats_enabled)
623 		return;
624 
625 	/* This is a safe check since VFS_STATS must be set (see above) */
626 	if ((vskap = vfsp->vfs_vskap) == NULL)
627 		return;
628 
629 	/* Whack the pointer right away */
630 	vfsp->vfs_vskap = NULL;
631 
632 	/* Lock the tree, remove the node, and delete the kstat */
633 	mutex_enter(&vskstat_tree_lock);
634 	if (avl_find(&vskstat_tree, vskap, &where)) {
635 		avl_remove(&vskstat_tree, vskap);
636 	}
637 
638 	if (vskap->vsk_ksp) {
639 		kstat_delete(vskap->vsk_ksp);
640 	}
641 	mutex_exit(&vskstat_tree_lock);
642 
643 	kmem_cache_free(vsk_anchor_cache, vskap);
644 }
645 
646 /*
647  * Read or write a vnode.  Called from kernel code.
648  */
649 int
650 vn_rdwr(
651 	enum uio_rw rw,
652 	struct vnode *vp,
653 	caddr_t base,
654 	ssize_t len,
655 	offset_t offset,
656 	enum uio_seg seg,
657 	int ioflag,
658 	rlim64_t ulimit,	/* meaningful only if rw is UIO_WRITE */
659 	cred_t *cr,
660 	ssize_t *residp)
661 {
662 	struct uio uio;
663 	struct iovec iov;
664 	int error;
665 	int in_crit = 0;
666 
667 	if (rw == UIO_WRITE && ISROFILE(vp))
668 		return (EROFS);
669 
670 	if (len < 0)
671 		return (EIO);
672 
673 	iov.iov_base = base;
674 	iov.iov_len = len;
675 	uio.uio_iov = &iov;
676 	uio.uio_iovcnt = 1;
677 	uio.uio_loffset = offset;
678 	uio.uio_segflg = (short)seg;
679 	uio.uio_resid = len;
680 	uio.uio_llimit = ulimit;
681 
682 	/*
683 	 * We have to enter the critical region before calling VOP_RWLOCK
684 	 * to avoid a deadlock with ufs.
685 	 */
686 	if (nbl_need_check(vp)) {
687 		int svmand;
688 
689 		nbl_start_crit(vp, RW_READER);
690 		in_crit = 1;
691 		error = nbl_svmand(vp, cr, &svmand);
692 		if (error != 0)
693 			goto done;
694 		if (nbl_conflict(vp, rw == UIO_WRITE ? NBL_WRITE : NBL_READ,
695 		    uio.uio_offset, uio.uio_resid, svmand)) {
696 			error = EACCES;
697 			goto done;
698 		}
699 	}
700 
701 	(void) VOP_RWLOCK(vp,
702 		rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE, NULL);
703 	if (rw == UIO_WRITE) {
704 		uio.uio_fmode = FWRITE;
705 		uio.uio_extflg = UIO_COPY_DEFAULT;
706 		error = VOP_WRITE(vp, &uio, ioflag, cr, NULL);
707 	} else {
708 		uio.uio_fmode = FREAD;
709 		uio.uio_extflg = UIO_COPY_CACHED;
710 		error = VOP_READ(vp, &uio, ioflag, cr, NULL);
711 	}
712 	VOP_RWUNLOCK(vp, rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE,
713 									NULL);
714 	if (residp)
715 		*residp = uio.uio_resid;
716 	else if (uio.uio_resid)
717 		error = EIO;
718 
719 done:
720 	if (in_crit)
721 		nbl_end_crit(vp);
722 	return (error);
723 }
724 
725 /*
726  * Release a vnode.  Call VOP_INACTIVE on last reference or
727  * decrement reference count.
728  *
729  * To avoid race conditions, the v_count is left at 1 for
730  * the call to VOP_INACTIVE. This prevents another thread
731  * from reclaiming and releasing the vnode *before* the
732  * VOP_INACTIVE routine has a chance to destroy the vnode.
733  * We can't have more than 1 thread calling VOP_INACTIVE
734  * on a vnode.
735  */
736 void
737 vn_rele(vnode_t *vp)
738 {
739 	if (vp->v_count == 0)
740 		cmn_err(CE_PANIC, "vn_rele: vnode ref count 0");
741 	mutex_enter(&vp->v_lock);
742 	if (vp->v_count == 1) {
743 		mutex_exit(&vp->v_lock);
744 		VOP_INACTIVE(vp, CRED());
745 	} else {
746 		vp->v_count--;
747 		mutex_exit(&vp->v_lock);
748 	}
749 }
750 
751 /*
752  * Like vn_rele() except that it clears v_stream under v_lock.
753  * This is used by sockfs when it dismantels the association between
754  * the sockfs node and the vnode in the underlaying file system.
755  * v_lock has to be held to prevent a thread coming through the lookupname
756  * path from accessing a stream head that is going away.
757  */
758 void
759 vn_rele_stream(vnode_t *vp)
760 {
761 	if (vp->v_count == 0)
762 		cmn_err(CE_PANIC, "vn_rele: vnode ref count 0");
763 	mutex_enter(&vp->v_lock);
764 	vp->v_stream = NULL;
765 	if (vp->v_count == 1) {
766 		mutex_exit(&vp->v_lock);
767 		VOP_INACTIVE(vp, CRED());
768 	} else {
769 		vp->v_count--;
770 		mutex_exit(&vp->v_lock);
771 	}
772 }
773 
774 int
775 vn_open(
776 	char *pnamep,
777 	enum uio_seg seg,
778 	int filemode,
779 	int createmode,
780 	struct vnode **vpp,
781 	enum create crwhy,
782 	mode_t umask)
783 {
784 	return (vn_openat(pnamep, seg, filemode,
785 			createmode, vpp, crwhy, umask, NULL));
786 }
787 
788 
789 /*
790  * Open/create a vnode.
791  * This may be callable by the kernel, the only known use
792  * of user context being that the current user credentials
793  * are used for permissions.  crwhy is defined iff filemode & FCREAT.
794  */
795 int
796 vn_openat(
797 	char *pnamep,
798 	enum uio_seg seg,
799 	int filemode,
800 	int createmode,
801 	struct vnode **vpp,
802 	enum create crwhy,
803 	mode_t umask,
804 	struct vnode *startvp)
805 {
806 	struct vnode *vp;
807 	int mode;
808 	int error;
809 	int in_crit = 0;
810 	struct vattr vattr;
811 	enum symfollow follow;
812 	int estale_retry = 0;
813 
814 	mode = 0;
815 	if (filemode & FREAD)
816 		mode |= VREAD;
817 	if (filemode & (FWRITE|FTRUNC))
818 		mode |= VWRITE;
819 
820 	/* symlink interpretation */
821 	if (filemode & FNOFOLLOW)
822 		follow = NO_FOLLOW;
823 	else
824 		follow = FOLLOW;
825 
826 top:
827 	if (filemode & FCREAT) {
828 		enum vcexcl excl;
829 
830 		/*
831 		 * Wish to create a file.
832 		 */
833 		vattr.va_type = VREG;
834 		vattr.va_mode = createmode;
835 		vattr.va_mask = AT_TYPE|AT_MODE;
836 		if (filemode & FTRUNC) {
837 			vattr.va_size = 0;
838 			vattr.va_mask |= AT_SIZE;
839 		}
840 		if (filemode & FEXCL)
841 			excl = EXCL;
842 		else
843 			excl = NONEXCL;
844 
845 		if (error =
846 		    vn_createat(pnamep, seg, &vattr, excl, mode, &vp, crwhy,
847 					(filemode & ~(FTRUNC|FEXCL)),
848 						umask, startvp))
849 			return (error);
850 	} else {
851 		/*
852 		 * Wish to open a file.  Just look it up.
853 		 */
854 		if (error = lookupnameat(pnamep, seg, follow,
855 		    NULLVPP, &vp, startvp)) {
856 			if ((error == ESTALE) &&
857 			    fs_need_estale_retry(estale_retry++))
858 				goto top;
859 			return (error);
860 		}
861 
862 		/*
863 		 * Get the attributes to check whether file is large.
864 		 * We do this only if the FOFFMAX flag is not set and
865 		 * only for regular files.
866 		 */
867 
868 		if (!(filemode & FOFFMAX) && (vp->v_type == VREG)) {
869 			vattr.va_mask = AT_SIZE;
870 			if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
871 				goto out;
872 			}
873 			if (vattr.va_size > (u_offset_t)MAXOFF32_T) {
874 				/*
875 				 * Large File API - regular open fails
876 				 * if FOFFMAX flag is set in file mode
877 				 */
878 				error = EOVERFLOW;
879 				goto out;
880 			}
881 		}
882 		/*
883 		 * Can't write directories, active texts, or
884 		 * read-only filesystems.  Can't truncate files
885 		 * on which mandatory locking is in effect.
886 		 */
887 		if (filemode & (FWRITE|FTRUNC)) {
888 			/*
889 			 * Allow writable directory if VDIROPEN flag is set.
890 			 */
891 			if (vp->v_type == VDIR && !(vp->v_flag & VDIROPEN)) {
892 				error = EISDIR;
893 				goto out;
894 			}
895 			if (ISROFILE(vp)) {
896 				error = EROFS;
897 				goto out;
898 			}
899 			/*
900 			 * Can't truncate files on which mandatory locking
901 			 * or non-blocking mandatory locking is in effect.
902 			 */
903 			if (filemode & FTRUNC) {
904 				vnode_t *rvp;
905 
906 				if (VOP_REALVP(vp, &rvp) != 0)
907 					rvp = vp;
908 				if (nbl_need_check(vp)) {
909 					nbl_start_crit(vp, RW_READER);
910 					in_crit = 1;
911 					vattr.va_mask = AT_MODE|AT_SIZE;
912 					if ((error = VOP_GETATTR(vp, &vattr, 0,
913 					    CRED())) == 0) {
914 						if (rvp->v_filocks != NULL)
915 							if (MANDLOCK(vp,
916 							    vattr.va_mode))
917 								error = EAGAIN;
918 						if (!error) {
919 							if (nbl_conflict(vp,
920 							    NBL_WRITE, 0,
921 							    vattr.va_size, 0))
922 								error = EACCES;
923 						}
924 					}
925 				} else if (rvp->v_filocks != NULL) {
926 					vattr.va_mask = AT_MODE;
927 					if ((error = VOP_GETATTR(vp, &vattr,
928 					    0, CRED())) == 0 && MANDLOCK(vp,
929 					    vattr.va_mode))
930 						error = EAGAIN;
931 				}
932 			}
933 			if (error)
934 				goto out;
935 		}
936 		/*
937 		 * Check permissions.
938 		 */
939 		if (error = VOP_ACCESS(vp, mode, 0, CRED()))
940 			goto out;
941 	}
942 
943 	/*
944 	 * Do remaining checks for FNOFOLLOW and FNOLINKS.
945 	 */
946 	if ((filemode & FNOFOLLOW) && vp->v_type == VLNK) {
947 		error = ELOOP;
948 		goto out;
949 	}
950 	if (filemode & FNOLINKS) {
951 		vattr.va_mask = AT_NLINK;
952 		if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
953 			goto out;
954 		}
955 		if (vattr.va_nlink != 1) {
956 			error = EMLINK;
957 			goto out;
958 		}
959 	}
960 
961 	/*
962 	 * Opening a socket corresponding to the AF_UNIX pathname
963 	 * in the filesystem name space is not supported.
964 	 * However, VSOCK nodes in namefs are supported in order
965 	 * to make fattach work for sockets.
966 	 *
967 	 * XXX This uses VOP_REALVP to distinguish between
968 	 * an unopened namefs node (where VOP_REALVP returns a
969 	 * different VSOCK vnode) and a VSOCK created by vn_create
970 	 * in some file system (where VOP_REALVP would never return
971 	 * a different vnode).
972 	 */
973 	if (vp->v_type == VSOCK) {
974 		struct vnode *nvp;
975 
976 		error = VOP_REALVP(vp, &nvp);
977 		if (error != 0 || nvp == NULL || nvp == vp ||
978 		    nvp->v_type != VSOCK) {
979 			error = EOPNOTSUPP;
980 			goto out;
981 		}
982 	}
983 	/*
984 	 * Do opening protocol.
985 	 */
986 	error = VOP_OPEN(&vp, filemode, CRED());
987 	/*
988 	 * Truncate if required.
989 	 */
990 	if (error == 0 && (filemode & FTRUNC) && !(filemode & FCREAT)) {
991 		vattr.va_size = 0;
992 		vattr.va_mask = AT_SIZE;
993 		if ((error = VOP_SETATTR(vp, &vattr, 0, CRED(), NULL)) != 0)
994 			(void) VOP_CLOSE(vp, filemode, 1, (offset_t)0, CRED());
995 	}
996 out:
997 	ASSERT(vp->v_count > 0);
998 
999 	if (in_crit) {
1000 		nbl_end_crit(vp);
1001 		in_crit = 0;
1002 	}
1003 	if (error) {
1004 		/*
1005 		 * The following clause was added to handle a problem
1006 		 * with NFS consistency.  It is possible that a lookup
1007 		 * of the file to be opened succeeded, but the file
1008 		 * itself doesn't actually exist on the server.  This
1009 		 * is chiefly due to the DNLC containing an entry for
1010 		 * the file which has been removed on the server.  In
1011 		 * this case, we just start over.  If there was some
1012 		 * other cause for the ESTALE error, then the lookup
1013 		 * of the file will fail and the error will be returned
1014 		 * above instead of looping around from here.
1015 		 */
1016 		VN_RELE(vp);
1017 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1018 			goto top;
1019 	} else
1020 		*vpp = vp;
1021 	return (error);
1022 }
1023 
1024 int
1025 vn_create(
1026 	char *pnamep,
1027 	enum uio_seg seg,
1028 	struct vattr *vap,
1029 	enum vcexcl excl,
1030 	int mode,
1031 	struct vnode **vpp,
1032 	enum create why,
1033 	int flag,
1034 	mode_t umask)
1035 {
1036 	return (vn_createat(pnamep, seg, vap, excl, mode, vpp,
1037 			why, flag, umask, NULL));
1038 }
1039 
1040 /*
1041  * Create a vnode (makenode).
1042  */
1043 int
1044 vn_createat(
1045 	char *pnamep,
1046 	enum uio_seg seg,
1047 	struct vattr *vap,
1048 	enum vcexcl excl,
1049 	int mode,
1050 	struct vnode **vpp,
1051 	enum create why,
1052 	int flag,
1053 	mode_t umask,
1054 	struct vnode *startvp)
1055 {
1056 	struct vnode *dvp;	/* ptr to parent dir vnode */
1057 	struct vnode *vp = NULL;
1058 	struct pathname pn;
1059 	int error;
1060 	int in_crit = 0;
1061 	struct vattr vattr;
1062 	enum symfollow follow;
1063 	int estale_retry = 0;
1064 
1065 	ASSERT((vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));
1066 
1067 	/* symlink interpretation */
1068 	if ((flag & FNOFOLLOW) || excl == EXCL)
1069 		follow = NO_FOLLOW;
1070 	else
1071 		follow = FOLLOW;
1072 	flag &= ~(FNOFOLLOW|FNOLINKS);
1073 
1074 top:
1075 	/*
1076 	 * Lookup directory.
1077 	 * If new object is a file, call lower level to create it.
1078 	 * Note that it is up to the lower level to enforce exclusive
1079 	 * creation, if the file is already there.
1080 	 * This allows the lower level to do whatever
1081 	 * locking or protocol that is needed to prevent races.
1082 	 * If the new object is directory call lower level to make
1083 	 * the new directory, with "." and "..".
1084 	 */
1085 	if (error = pn_get(pnamep, seg, &pn))
1086 		return (error);
1087 #ifdef  C2_AUDIT
1088 	if (audit_active)
1089 		audit_vncreate_start();
1090 #endif /* C2_AUDIT */
1091 	dvp = NULL;
1092 	*vpp = NULL;
1093 	/*
1094 	 * lookup will find the parent directory for the vnode.
1095 	 * When it is done the pn holds the name of the entry
1096 	 * in the directory.
1097 	 * If this is a non-exclusive create we also find the node itself.
1098 	 */
1099 	error = lookuppnat(&pn, NULL, follow, &dvp,
1100 	    (excl == EXCL) ? NULLVPP : vpp, startvp);
1101 	if (error) {
1102 		pn_free(&pn);
1103 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1104 			goto top;
1105 		if (why == CRMKDIR && error == EINVAL)
1106 			error = EEXIST;		/* SVID */
1107 		return (error);
1108 	}
1109 
1110 	if (why != CRMKNOD)
1111 		vap->va_mode &= ~VSVTX;
1112 
1113 	/*
1114 	 * If default ACLs are defined for the directory don't apply the
1115 	 * umask if umask is passed.
1116 	 */
1117 
1118 	if (umask) {
1119 
1120 		vsecattr_t vsec;
1121 
1122 		vsec.vsa_aclcnt = 0;
1123 		vsec.vsa_aclentp = NULL;
1124 		vsec.vsa_dfaclcnt = 0;
1125 		vsec.vsa_dfaclentp = NULL;
1126 		vsec.vsa_mask = VSA_DFACLCNT;
1127 		error =  VOP_GETSECATTR(dvp, &vsec, 0, CRED());
1128 		/*
1129 		 * If error is ENOSYS then treat it as no error
1130 		 * Don't want to force all file systems to support
1131 		 * aclent_t style of ACL's.
1132 		 */
1133 		if (error == ENOSYS)
1134 			error = 0;
1135 		if (error) {
1136 			if (*vpp != NULL)
1137 				VN_RELE(*vpp);
1138 			goto out;
1139 		} else {
1140 			/*
1141 			 * Apply the umask if no default ACLs.
1142 			 */
1143 			if (vsec.vsa_dfaclcnt == 0)
1144 				vap->va_mode &= ~umask;
1145 
1146 			/*
1147 			 * VOP_GETSECATTR() may have allocated memory for
1148 			 * ACLs we didn't request, so double-check and
1149 			 * free it if necessary.
1150 			 */
1151 			if (vsec.vsa_aclcnt && vsec.vsa_aclentp != NULL)
1152 				kmem_free((caddr_t)vsec.vsa_aclentp,
1153 				    vsec.vsa_aclcnt * sizeof (aclent_t));
1154 			if (vsec.vsa_dfaclcnt && vsec.vsa_dfaclentp != NULL)
1155 				kmem_free((caddr_t)vsec.vsa_dfaclentp,
1156 				    vsec.vsa_dfaclcnt * sizeof (aclent_t));
1157 		}
1158 	}
1159 
1160 	/*
1161 	 * In general we want to generate EROFS if the file system is
1162 	 * readonly.  However, POSIX (IEEE Std. 1003.1) section 5.3.1
1163 	 * documents the open system call, and it says that O_CREAT has no
1164 	 * effect if the file already exists.  Bug 1119649 states
1165 	 * that open(path, O_CREAT, ...) fails when attempting to open an
1166 	 * existing file on a read only file system.  Thus, the first part
1167 	 * of the following if statement has 3 checks:
1168 	 *	if the file exists &&
1169 	 *		it is being open with write access &&
1170 	 *		the file system is read only
1171 	 *	then generate EROFS
1172 	 */
1173 	if ((*vpp != NULL && (mode & VWRITE) && ISROFILE(*vpp)) ||
1174 	    (*vpp == NULL && dvp->v_vfsp->vfs_flag & VFS_RDONLY)) {
1175 		if (*vpp)
1176 			VN_RELE(*vpp);
1177 		error = EROFS;
1178 	} else if (excl == NONEXCL && *vpp != NULL) {
1179 		vnode_t *rvp;
1180 
1181 		/*
1182 		 * File already exists.  If a mandatory lock has been
1183 		 * applied, return error.
1184 		 */
1185 		vp = *vpp;
1186 		if (VOP_REALVP(vp, &rvp) != 0)
1187 			rvp = vp;
1188 		if ((vap->va_mask & AT_SIZE) && nbl_need_check(vp)) {
1189 			nbl_start_crit(vp, RW_READER);
1190 			in_crit = 1;
1191 		}
1192 		if (rvp->v_filocks != NULL || rvp->v_shrlocks != NULL) {
1193 			vattr.va_mask = AT_MODE|AT_SIZE;
1194 			if (error = VOP_GETATTR(vp, &vattr, 0, CRED())) {
1195 				goto out;
1196 			}
1197 			if (MANDLOCK(vp, vattr.va_mode)) {
1198 				error = EAGAIN;
1199 				goto out;
1200 			}
1201 			/*
1202 			 * File cannot be truncated if non-blocking mandatory
1203 			 * locks are currently on the file.
1204 			 */
1205 			if ((vap->va_mask & AT_SIZE) && in_crit) {
1206 				u_offset_t offset;
1207 				ssize_t length;
1208 
1209 				offset = vap->va_size > vattr.va_size ?
1210 						vattr.va_size : vap->va_size;
1211 				length = vap->va_size > vattr.va_size ?
1212 						vap->va_size - vattr.va_size :
1213 						vattr.va_size - vap->va_size;
1214 				if (nbl_conflict(vp, NBL_WRITE, offset,
1215 						length, 0)) {
1216 					error = EACCES;
1217 					goto out;
1218 				}
1219 			}
1220 		}
1221 
1222 		/*
1223 		 * If the file is the root of a VFS, we've crossed a
1224 		 * mount point and the "containing" directory that we
1225 		 * acquired above (dvp) is irrelevant because it's in
1226 		 * a different file system.  We apply VOP_CREATE to the
1227 		 * target itself instead of to the containing directory
1228 		 * and supply a null path name to indicate (conventionally)
1229 		 * the node itself as the "component" of interest.
1230 		 *
1231 		 * The intercession of the file system is necessary to
1232 		 * ensure that the appropriate permission checks are
1233 		 * done.
1234 		 */
1235 		if (vp->v_flag & VROOT) {
1236 			ASSERT(why != CRMKDIR);
1237 			error =
1238 			    VOP_CREATE(vp, "", vap, excl, mode, vpp, CRED(),
1239 				    flag);
1240 			/*
1241 			 * If the create succeeded, it will have created
1242 			 * a new reference to the vnode.  Give up the
1243 			 * original reference.  The assertion should not
1244 			 * get triggered because NBMAND locks only apply to
1245 			 * VREG files.  And if in_crit is non-zero for some
1246 			 * reason, detect that here, rather than when we
1247 			 * deference a null vp.
1248 			 */
1249 			ASSERT(in_crit == 0);
1250 			VN_RELE(vp);
1251 			vp = NULL;
1252 			goto out;
1253 		}
1254 
1255 		/*
1256 		 * Large File API - non-large open (FOFFMAX flag not set)
1257 		 * of regular file fails if the file size exceeds MAXOFF32_T.
1258 		 */
1259 		if (why != CRMKDIR &&
1260 		    !(flag & FOFFMAX) &&
1261 		    (vp->v_type == VREG)) {
1262 			vattr.va_mask = AT_SIZE;
1263 			if ((error = VOP_GETATTR(vp, &vattr, 0, CRED()))) {
1264 				goto out;
1265 			}
1266 			if ((vattr.va_size > (u_offset_t)MAXOFF32_T)) {
1267 				error = EOVERFLOW;
1268 				goto out;
1269 			}
1270 		}
1271 	}
1272 
1273 	if (error == 0) {
1274 		/*
1275 		 * Call mkdir() if specified, otherwise create().
1276 		 */
1277 		int must_be_dir = pn_fixslash(&pn);	/* trailing '/'? */
1278 
1279 		if (why == CRMKDIR)
1280 			error = VOP_MKDIR(dvp, pn.pn_path, vap, vpp, CRED());
1281 		else if (!must_be_dir)
1282 			error = VOP_CREATE(dvp, pn.pn_path, vap,
1283 			    excl, mode, vpp, CRED(), flag);
1284 		else
1285 			error = ENOTDIR;
1286 	}
1287 
1288 out:
1289 
1290 #ifdef C2_AUDIT
1291 	if (audit_active)
1292 		audit_vncreate_finish(*vpp, error);
1293 #endif  /* C2_AUDIT */
1294 	if (in_crit) {
1295 		nbl_end_crit(vp);
1296 		in_crit = 0;
1297 	}
1298 	if (vp != NULL) {
1299 		VN_RELE(vp);
1300 		vp = NULL;
1301 	}
1302 	pn_free(&pn);
1303 	VN_RELE(dvp);
1304 	/*
1305 	 * The following clause was added to handle a problem
1306 	 * with NFS consistency.  It is possible that a lookup
1307 	 * of the file to be created succeeded, but the file
1308 	 * itself doesn't actually exist on the server.  This
1309 	 * is chiefly due to the DNLC containing an entry for
1310 	 * the file which has been removed on the server.  In
1311 	 * this case, we just start over.  If there was some
1312 	 * other cause for the ESTALE error, then the lookup
1313 	 * of the file will fail and the error will be returned
1314 	 * above instead of looping around from here.
1315 	 */
1316 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1317 		goto top;
1318 	return (error);
1319 }
1320 
1321 int
1322 vn_link(char *from, char *to, enum uio_seg seg)
1323 {
1324 	struct vnode *fvp;		/* from vnode ptr */
1325 	struct vnode *tdvp;		/* to directory vnode ptr */
1326 	struct pathname pn;
1327 	int error;
1328 	struct vattr vattr;
1329 	dev_t fsid;
1330 	int estale_retry = 0;
1331 
1332 top:
1333 	fvp = tdvp = NULL;
1334 	if (error = pn_get(to, seg, &pn))
1335 		return (error);
1336 	if (error = lookupname(from, seg, NO_FOLLOW, NULLVPP, &fvp))
1337 		goto out;
1338 	if (error = lookuppn(&pn, NULL, NO_FOLLOW, &tdvp, NULLVPP))
1339 		goto out;
1340 	/*
1341 	 * Make sure both source vnode and target directory vnode are
1342 	 * in the same vfs and that it is writeable.
1343 	 */
1344 	vattr.va_mask = AT_FSID;
1345 	if (error = VOP_GETATTR(fvp, &vattr, 0, CRED()))
1346 		goto out;
1347 	fsid = vattr.va_fsid;
1348 	vattr.va_mask = AT_FSID;
1349 	if (error = VOP_GETATTR(tdvp, &vattr, 0, CRED()))
1350 		goto out;
1351 	if (fsid != vattr.va_fsid) {
1352 		error = EXDEV;
1353 		goto out;
1354 	}
1355 	if (tdvp->v_vfsp->vfs_flag & VFS_RDONLY) {
1356 		error = EROFS;
1357 		goto out;
1358 	}
1359 	/*
1360 	 * Do the link.
1361 	 */
1362 	(void) pn_fixslash(&pn);
1363 	error = VOP_LINK(tdvp, fvp, pn.pn_path, CRED());
1364 out:
1365 	pn_free(&pn);
1366 	if (fvp)
1367 		VN_RELE(fvp);
1368 	if (tdvp)
1369 		VN_RELE(tdvp);
1370 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1371 		goto top;
1372 	return (error);
1373 }
1374 
1375 int
1376 vn_rename(char *from, char *to, enum uio_seg seg)
1377 {
1378 	return (vn_renameat(NULL, from, NULL, to, seg));
1379 }
1380 
1381 int
1382 vn_renameat(vnode_t *fdvp, char *fname, vnode_t *tdvp,
1383 		char *tname, enum uio_seg seg)
1384 {
1385 	int error;
1386 	struct vattr vattr;
1387 	struct pathname fpn;		/* from pathname */
1388 	struct pathname tpn;		/* to pathname */
1389 	dev_t fsid;
1390 	int in_crit = 0;
1391 	vnode_t *fromvp, *fvp;
1392 	vnode_t *tovp;
1393 	int estale_retry = 0;
1394 
1395 top:
1396 	fvp = fromvp = tovp = NULL;
1397 	/*
1398 	 * Get to and from pathnames.
1399 	 */
1400 	if (error = pn_get(fname, seg, &fpn))
1401 		return (error);
1402 	if (error = pn_get(tname, seg, &tpn)) {
1403 		pn_free(&fpn);
1404 		return (error);
1405 	}
1406 
1407 	/*
1408 	 * First we need to resolve the correct directories
1409 	 * The passed in directories may only be a starting point,
1410 	 * but we need the real directories the file(s) live in.
1411 	 * For example the fname may be something like usr/lib/sparc
1412 	 * and we were passed in the / directory, but we need to
1413 	 * use the lib directory for the rename.
1414 	 */
1415 
1416 #ifdef  C2_AUDIT
1417 	if (audit_active)
1418 		audit_setfsat_path(1);
1419 #endif /* C2_AUDIT */
1420 	/*
1421 	 * Lookup to and from directories.
1422 	 */
1423 	if (error = lookuppnat(&fpn, NULL, NO_FOLLOW, &fromvp, &fvp, fdvp)) {
1424 		goto out;
1425 	}
1426 
1427 	/*
1428 	 * Make sure there is an entry.
1429 	 */
1430 	if (fvp == NULL) {
1431 		error = ENOENT;
1432 		goto out;
1433 	}
1434 
1435 #ifdef  C2_AUDIT
1436 	if (audit_active)
1437 		audit_setfsat_path(3);
1438 #endif /* C2_AUDIT */
1439 	if (error = lookuppnat(&tpn, NULL, NO_FOLLOW, &tovp, NULLVPP, tdvp)) {
1440 		goto out;
1441 	}
1442 
1443 	/*
1444 	 * Make sure both the from vnode directory and the to directory
1445 	 * are in the same vfs and the to directory is writable.
1446 	 * We check fsid's, not vfs pointers, so loopback fs works.
1447 	 */
1448 	if (fromvp != tovp) {
1449 		vattr.va_mask = AT_FSID;
1450 		if (error = VOP_GETATTR(fromvp, &vattr, 0, CRED()))
1451 			goto out;
1452 		fsid = vattr.va_fsid;
1453 		vattr.va_mask = AT_FSID;
1454 		if (error = VOP_GETATTR(tovp, &vattr, 0, CRED()))
1455 			goto out;
1456 		if (fsid != vattr.va_fsid) {
1457 			error = EXDEV;
1458 			goto out;
1459 		}
1460 	}
1461 
1462 	if (tovp->v_vfsp->vfs_flag & VFS_RDONLY) {
1463 		error = EROFS;
1464 		goto out;
1465 	}
1466 
1467 	if (nbl_need_check(fvp)) {
1468 		nbl_start_crit(fvp, RW_READER);
1469 		in_crit = 1;
1470 		if (nbl_conflict(fvp, NBL_RENAME, 0, 0, 0)) {
1471 			error = EACCES;
1472 			goto out;
1473 		}
1474 	}
1475 
1476 	/*
1477 	 * Do the rename.
1478 	 */
1479 	(void) pn_fixslash(&tpn);
1480 	error = VOP_RENAME(fromvp, fpn.pn_path, tovp, tpn.pn_path, CRED());
1481 
1482 out:
1483 	pn_free(&fpn);
1484 	pn_free(&tpn);
1485 	if (in_crit) {
1486 		nbl_end_crit(fvp);
1487 		in_crit = 0;
1488 	}
1489 	if (fromvp)
1490 		VN_RELE(fromvp);
1491 	if (tovp)
1492 		VN_RELE(tovp);
1493 	if (fvp)
1494 		VN_RELE(fvp);
1495 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1496 		goto top;
1497 	return (error);
1498 }
1499 
1500 /*
1501  * Remove a file or directory.
1502  */
1503 int
1504 vn_remove(char *fnamep, enum uio_seg seg, enum rm dirflag)
1505 {
1506 	return (vn_removeat(NULL, fnamep, seg, dirflag));
1507 }
1508 
1509 int
1510 vn_removeat(vnode_t *startvp, char *fnamep, enum uio_seg seg, enum rm dirflag)
1511 {
1512 	struct vnode *vp;		/* entry vnode */
1513 	struct vnode *dvp;		/* ptr to parent dir vnode */
1514 	struct vnode *coveredvp;
1515 	struct pathname pn;		/* name of entry */
1516 	enum vtype vtype;
1517 	int error;
1518 	struct vfs *vfsp;
1519 	struct vfs *dvfsp;	/* ptr to parent dir vfs */
1520 	int in_crit = 0;
1521 	int estale_retry = 0;
1522 
1523 top:
1524 	if (error = pn_get(fnamep, seg, &pn))
1525 		return (error);
1526 	dvp = vp = NULL;
1527 	if (error = lookuppnat(&pn, NULL, NO_FOLLOW, &dvp, &vp, startvp)) {
1528 		pn_free(&pn);
1529 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1530 			goto top;
1531 		return (error);
1532 	}
1533 
1534 	/*
1535 	 * Make sure there is an entry.
1536 	 */
1537 	if (vp == NULL) {
1538 		error = ENOENT;
1539 		goto out;
1540 	}
1541 
1542 	vfsp = vp->v_vfsp;
1543 	dvfsp = dvp->v_vfsp;
1544 
1545 	/*
1546 	 * If the named file is the root of a mounted filesystem, fail,
1547 	 * unless it's marked unlinkable.  In that case, unmount the
1548 	 * filesystem and proceed to unlink the covered vnode.  (If the
1549 	 * covered vnode is a directory, use rmdir instead of unlink,
1550 	 * to avoid file system corruption.)
1551 	 */
1552 	if (vp->v_flag & VROOT) {
1553 		if (vfsp->vfs_flag & VFS_UNLINKABLE) {
1554 			if (dirflag == RMDIRECTORY) {
1555 				/*
1556 				 * User called rmdir(2) on a file that has
1557 				 * been namefs mounted on top of.  Since
1558 				 * namefs doesn't allow directories to
1559 				 * be mounted on other files we know
1560 				 * vp is not of type VDIR so fail to operation.
1561 				 */
1562 				error = ENOTDIR;
1563 				goto out;
1564 			}
1565 			coveredvp = vfsp->vfs_vnodecovered;
1566 			VN_HOLD(coveredvp);
1567 			VN_RELE(vp);
1568 			vp = NULL;
1569 			if ((error = vn_vfswlock(coveredvp)) == 0)
1570 				error = dounmount(vfsp, 0, CRED());
1571 			/*
1572 			 * Unmounted the namefs file system; now get
1573 			 * the object it was mounted over.
1574 			 */
1575 			vp = coveredvp;
1576 			/*
1577 			 * If namefs was mounted over a directory, then
1578 			 * we want to use rmdir() instead of unlink().
1579 			 */
1580 			if (vp->v_type == VDIR)
1581 				dirflag = RMDIRECTORY;
1582 		} else
1583 			error = EBUSY;
1584 
1585 		if (error)
1586 			goto out;
1587 	}
1588 
1589 	/*
1590 	 * Make sure filesystem is writeable.
1591 	 * We check the parent directory's vfs in case this is an lofs vnode.
1592 	 */
1593 	if (dvfsp && dvfsp->vfs_flag & VFS_RDONLY) {
1594 		error = EROFS;
1595 		goto out;
1596 	}
1597 
1598 	vtype = vp->v_type;
1599 
1600 	/*
1601 	 * If there is the possibility of an nbmand share reservation, make
1602 	 * sure it's okay to remove the file.  Keep a reference to the
1603 	 * vnode, so that we can exit the nbl critical region after
1604 	 * calling VOP_REMOVE.
1605 	 * If there is no possibility of an nbmand share reservation,
1606 	 * release the vnode reference now.  Filesystems like NFS may
1607 	 * behave differently if there is an extra reference, so get rid of
1608 	 * this one.  Fortunately, we can't have nbmand mounts on NFS
1609 	 * filesystems.
1610 	 */
1611 	if (nbl_need_check(vp)) {
1612 		nbl_start_crit(vp, RW_READER);
1613 		in_crit = 1;
1614 		if (nbl_conflict(vp, NBL_REMOVE, 0, 0, 0)) {
1615 			error = EACCES;
1616 			goto out;
1617 		}
1618 	} else {
1619 		VN_RELE(vp);
1620 		vp = NULL;
1621 	}
1622 
1623 	if (dirflag == RMDIRECTORY) {
1624 		/*
1625 		 * Caller is using rmdir(2), which can only be applied to
1626 		 * directories.
1627 		 */
1628 		if (vtype != VDIR) {
1629 			error = ENOTDIR;
1630 		} else {
1631 			vnode_t *cwd;
1632 			proc_t *pp = curproc;
1633 
1634 			mutex_enter(&pp->p_lock);
1635 			cwd = PTOU(pp)->u_cdir;
1636 			VN_HOLD(cwd);
1637 			mutex_exit(&pp->p_lock);
1638 			error = VOP_RMDIR(dvp, pn.pn_path, cwd, CRED());
1639 			VN_RELE(cwd);
1640 		}
1641 	} else {
1642 		/*
1643 		 * Unlink(2) can be applied to anything.
1644 		 */
1645 		error = VOP_REMOVE(dvp, pn.pn_path, CRED());
1646 	}
1647 
1648 out:
1649 	pn_free(&pn);
1650 	if (in_crit) {
1651 		nbl_end_crit(vp);
1652 		in_crit = 0;
1653 	}
1654 	if (vp != NULL)
1655 		VN_RELE(vp);
1656 	if (dvp != NULL)
1657 		VN_RELE(dvp);
1658 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1659 		goto top;
1660 	return (error);
1661 }
1662 
1663 /*
1664  * Utility function to compare equality of vnodes.
1665  * Compare the underlying real vnodes, if there are underlying vnodes.
1666  * This is a more thorough comparison than the VN_CMP() macro provides.
1667  */
1668 int
1669 vn_compare(vnode_t *vp1, vnode_t *vp2)
1670 {
1671 	vnode_t *realvp;
1672 
1673 	if (vp1 != NULL && VOP_REALVP(vp1, &realvp) == 0)
1674 		vp1 = realvp;
1675 	if (vp2 != NULL && VOP_REALVP(vp2, &realvp) == 0)
1676 		vp2 = realvp;
1677 	return (VN_CMP(vp1, vp2));
1678 }
1679 
1680 /*
1681  * The number of locks to hash into.  This value must be a power
1682  * of 2 minus 1 and should probably also be prime.
1683  */
1684 #define	NUM_BUCKETS	1023
1685 
1686 struct  vn_vfslocks_bucket {
1687 	kmutex_t vb_lock;
1688 	vn_vfslocks_entry_t *vb_list;
1689 	char pad[64 - sizeof (kmutex_t) - sizeof (void *)];
1690 };
1691 
1692 /*
1693  * Total number of buckets will be NUM_BUCKETS + 1 .
1694  */
1695 
1696 #pragma	align	64(vn_vfslocks_buckets)
1697 static	struct vn_vfslocks_bucket	vn_vfslocks_buckets[NUM_BUCKETS + 1];
1698 
1699 #define	VN_VFSLOCKS_SHIFT	9
1700 
1701 #define	VN_VFSLOCKS_HASH(vfsvpptr)	\
1702 	((((intptr_t)(vfsvpptr)) >> VN_VFSLOCKS_SHIFT) & NUM_BUCKETS)
1703 
1704 /*
1705  * vn_vfslocks_getlock() uses an HASH scheme to generate
1706  * rwstlock using vfs/vnode pointer passed to it.
1707  *
1708  * vn_vfslocks_rele() releases a reference in the
1709  * HASH table which allows the entry allocated by
1710  * vn_vfslocks_getlock() to be freed at a later
1711  * stage when the refcount drops to zero.
1712  */
1713 
1714 vn_vfslocks_entry_t *
1715 vn_vfslocks_getlock(void *vfsvpptr)
1716 {
1717 	struct vn_vfslocks_bucket *bp;
1718 	vn_vfslocks_entry_t *vep;
1719 	vn_vfslocks_entry_t *tvep;
1720 
1721 	ASSERT(vfsvpptr != NULL);
1722 	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vfsvpptr)];
1723 
1724 	mutex_enter(&bp->vb_lock);
1725 	for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
1726 		if (vep->ve_vpvfs == vfsvpptr) {
1727 			vep->ve_refcnt++;
1728 			mutex_exit(&bp->vb_lock);
1729 			return (vep);
1730 		}
1731 	}
1732 	mutex_exit(&bp->vb_lock);
1733 	vep = kmem_alloc(sizeof (*vep), KM_SLEEP);
1734 	rwst_init(&vep->ve_lock, NULL, RW_DEFAULT, NULL);
1735 	vep->ve_vpvfs = (char *)vfsvpptr;
1736 	vep->ve_refcnt = 1;
1737 	mutex_enter(&bp->vb_lock);
1738 	for (tvep = bp->vb_list; tvep != NULL; tvep = tvep->ve_next) {
1739 		if (tvep->ve_vpvfs == vfsvpptr) {
1740 			tvep->ve_refcnt++;
1741 			mutex_exit(&bp->vb_lock);
1742 
1743 			/*
1744 			 * There is already an entry in the hash
1745 			 * destroy what we just allocated.
1746 			 */
1747 			rwst_destroy(&vep->ve_lock);
1748 			kmem_free(vep, sizeof (*vep));
1749 			return (tvep);
1750 		}
1751 	}
1752 	vep->ve_next = bp->vb_list;
1753 	bp->vb_list = vep;
1754 	mutex_exit(&bp->vb_lock);
1755 	return (vep);
1756 }
1757 
1758 void
1759 vn_vfslocks_rele(vn_vfslocks_entry_t *vepent)
1760 {
1761 	struct vn_vfslocks_bucket *bp;
1762 	vn_vfslocks_entry_t *vep;
1763 	vn_vfslocks_entry_t *pvep;
1764 
1765 	ASSERT(vepent != NULL);
1766 	ASSERT(vepent->ve_vpvfs != NULL);
1767 
1768 	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vepent->ve_vpvfs)];
1769 
1770 	mutex_enter(&bp->vb_lock);
1771 	vepent->ve_refcnt--;
1772 
1773 	if ((int32_t)vepent->ve_refcnt < 0)
1774 		cmn_err(CE_PANIC, "vn_vfslocks_rele: refcount negative");
1775 
1776 	if (vepent->ve_refcnt == 0) {
1777 		for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
1778 			if (vep->ve_vpvfs == vepent->ve_vpvfs) {
1779 				if (bp->vb_list == vep)
1780 					bp->vb_list = vep->ve_next;
1781 				else {
1782 					/* LINTED */
1783 					pvep->ve_next = vep->ve_next;
1784 				}
1785 				mutex_exit(&bp->vb_lock);
1786 				rwst_destroy(&vep->ve_lock);
1787 				kmem_free(vep, sizeof (*vep));
1788 				return;
1789 			}
1790 			pvep = vep;
1791 		}
1792 		cmn_err(CE_PANIC, "vn_vfslocks_rele: vp/vfs not found");
1793 	}
1794 	mutex_exit(&bp->vb_lock);
1795 }
1796 
1797 /*
1798  * vn_vfswlock_wait is used to implement a lock which is logically a writers
1799  * lock protecting the v_vfsmountedhere field.
1800  * vn_vfswlock_wait has been modified to be similar to vn_vfswlock,
1801  * except that it blocks to acquire the lock VVFSLOCK.
1802  *
1803  * traverse() and routines re-implementing part of traverse (e.g. autofs)
1804  * need to hold this lock. mount(), vn_rename(), vn_remove() and so on
1805  * need the non-blocking version of the writers lock i.e. vn_vfswlock
1806  */
1807 int
1808 vn_vfswlock_wait(vnode_t *vp)
1809 {
1810 	int retval;
1811 	vn_vfslocks_entry_t *vpvfsentry;
1812 	ASSERT(vp != NULL);
1813 
1814 	vpvfsentry = vn_vfslocks_getlock(vp);
1815 	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_WRITER);
1816 
1817 	if (retval == EINTR) {
1818 		vn_vfslocks_rele(vpvfsentry);
1819 		return (EINTR);
1820 	}
1821 	return (retval);
1822 }
1823 
1824 int
1825 vn_vfsrlock_wait(vnode_t *vp)
1826 {
1827 	int retval;
1828 	vn_vfslocks_entry_t *vpvfsentry;
1829 	ASSERT(vp != NULL);
1830 
1831 	vpvfsentry = vn_vfslocks_getlock(vp);
1832 	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_READER);
1833 
1834 	if (retval == EINTR) {
1835 		vn_vfslocks_rele(vpvfsentry);
1836 		return (EINTR);
1837 	}
1838 
1839 	return (retval);
1840 }
1841 
1842 
1843 /*
1844  * vn_vfswlock is used to implement a lock which is logically a writers lock
1845  * protecting the v_vfsmountedhere field.
1846  */
1847 int
1848 vn_vfswlock(vnode_t *vp)
1849 {
1850 	vn_vfslocks_entry_t *vpvfsentry;
1851 
1852 	/*
1853 	 * If vp is NULL then somebody is trying to lock the covered vnode
1854 	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
1855 	 * only happen when unmounting /.  Since that operation will fail
1856 	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
1857 	 */
1858 	if (vp == NULL)
1859 		return (EBUSY);
1860 
1861 	vpvfsentry = vn_vfslocks_getlock(vp);
1862 
1863 	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_WRITER))
1864 		return (0);
1865 
1866 	vn_vfslocks_rele(vpvfsentry);
1867 	return (EBUSY);
1868 }
1869 
1870 int
1871 vn_vfsrlock(vnode_t *vp)
1872 {
1873 	vn_vfslocks_entry_t *vpvfsentry;
1874 
1875 	/*
1876 	 * If vp is NULL then somebody is trying to lock the covered vnode
1877 	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
1878 	 * only happen when unmounting /.  Since that operation will fail
1879 	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
1880 	 */
1881 	if (vp == NULL)
1882 		return (EBUSY);
1883 
1884 	vpvfsentry = vn_vfslocks_getlock(vp);
1885 
1886 	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_READER))
1887 		return (0);
1888 
1889 	vn_vfslocks_rele(vpvfsentry);
1890 	return (EBUSY);
1891 }
1892 
1893 void
1894 vn_vfsunlock(vnode_t *vp)
1895 {
1896 	vn_vfslocks_entry_t *vpvfsentry;
1897 
1898 	/*
1899 	 * ve_refcnt needs to be decremented twice.
1900 	 * 1. To release refernce after a call to vn_vfslocks_getlock()
1901 	 * 2. To release the reference from the locking routines like
1902 	 *    vn_vfsrlock/vn_vfswlock etc,.
1903 	 */
1904 	vpvfsentry = vn_vfslocks_getlock(vp);
1905 	vn_vfslocks_rele(vpvfsentry);
1906 
1907 	rwst_exit(&vpvfsentry->ve_lock);
1908 	vn_vfslocks_rele(vpvfsentry);
1909 }
1910 
1911 int
1912 vn_vfswlock_held(vnode_t *vp)
1913 {
1914 	int held;
1915 	vn_vfslocks_entry_t *vpvfsentry;
1916 
1917 	ASSERT(vp != NULL);
1918 
1919 	vpvfsentry = vn_vfslocks_getlock(vp);
1920 	held = rwst_lock_held(&vpvfsentry->ve_lock, RW_WRITER);
1921 
1922 	vn_vfslocks_rele(vpvfsentry);
1923 	return (held);
1924 }
1925 
1926 
1927 int
1928 vn_make_ops(
1929 	const char *name,			/* Name of file system */
1930 	const fs_operation_def_t *templ,	/* Operation specification */
1931 	vnodeops_t **actual)			/* Return the vnodeops */
1932 {
1933 	int unused_ops;
1934 	int error;
1935 
1936 	*actual = (vnodeops_t *)kmem_alloc(sizeof (vnodeops_t), KM_SLEEP);
1937 
1938 	(*actual)->vnop_name = name;
1939 
1940 	error = fs_build_vector(*actual, &unused_ops, vn_ops_table, templ);
1941 	if (error) {
1942 		kmem_free(*actual, sizeof (vnodeops_t));
1943 	}
1944 
1945 #if DEBUG
1946 	if (unused_ops != 0)
1947 		cmn_err(CE_WARN, "vn_make_ops: %s: %d operations supplied "
1948 		    "but not used", name, unused_ops);
1949 #endif
1950 
1951 	return (error);
1952 }
1953 
1954 /*
1955  * Free the vnodeops created as a result of vn_make_ops()
1956  */
1957 void
1958 vn_freevnodeops(vnodeops_t *vnops)
1959 {
1960 	kmem_free(vnops, sizeof (vnodeops_t));
1961 }
1962 
1963 /*
1964  * Vnode cache.
1965  */
1966 
1967 /* ARGSUSED */
1968 static int
1969 vn_cache_constructor(void *buf, void *cdrarg, int kmflags)
1970 {
1971 	struct vnode *vp;
1972 
1973 	vp = buf;
1974 
1975 	mutex_init(&vp->v_lock, NULL, MUTEX_DEFAULT, NULL);
1976 	cv_init(&vp->v_cv, NULL, CV_DEFAULT, NULL);
1977 	rw_init(&vp->v_nbllock, NULL, RW_DEFAULT, NULL);
1978 	rw_init(&vp->v_mslock, NULL, RW_DEFAULT, NULL);
1979 
1980 	vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
1981 	vp->v_path = NULL;
1982 	vp->v_mpssdata = NULL;
1983 
1984 	return (0);
1985 }
1986 
1987 /* ARGSUSED */
1988 static void
1989 vn_cache_destructor(void *buf, void *cdrarg)
1990 {
1991 	struct vnode *vp;
1992 
1993 	vp = buf;
1994 
1995 	rw_destroy(&vp->v_mslock);
1996 	rw_destroy(&vp->v_nbllock);
1997 	cv_destroy(&vp->v_cv);
1998 	mutex_destroy(&vp->v_lock);
1999 }
2000 
2001 void
2002 vn_create_cache(void)
2003 {
2004 	vn_cache = kmem_cache_create("vn_cache", sizeof (struct vnode), 64,
2005 	    vn_cache_constructor, vn_cache_destructor, NULL, NULL,
2006 	    NULL, 0);
2007 }
2008 
2009 void
2010 vn_destroy_cache(void)
2011 {
2012 	kmem_cache_destroy(vn_cache);
2013 }
2014 
2015 /*
2016  * Used by file systems when fs-specific nodes (e.g., ufs inodes) are
2017  * cached by the file system and vnodes remain associated.
2018  */
2019 void
2020 vn_recycle(vnode_t *vp)
2021 {
2022 	ASSERT(vp->v_pages == NULL);
2023 
2024 	/*
2025 	 * XXX - This really belongs in vn_reinit(), but we have some issues
2026 	 * with the counts.  Best to have it here for clean initialization.
2027 	 */
2028 	vp->v_rdcnt = 0;
2029 	vp->v_wrcnt = 0;
2030 	vp->v_mmap_read = 0;
2031 	vp->v_mmap_write = 0;
2032 
2033 	/*
2034 	 * If FEM was in use, make sure everything gets cleaned up
2035 	 * NOTE: vp->v_femhead is initialized to NULL in the vnode
2036 	 * constructor.
2037 	 */
2038 	if (vp->v_femhead) {
2039 		/* XXX - There should be a free_femhead() that does all this */
2040 		ASSERT(vp->v_femhead->femh_list == NULL);
2041 		mutex_destroy(&vp->v_femhead->femh_lock);
2042 		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
2043 		vp->v_femhead = NULL;
2044 	}
2045 	if (vp->v_path) {
2046 		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
2047 		vp->v_path = NULL;
2048 	}
2049 	vp->v_mpssdata = NULL;
2050 }
2051 
2052 /*
2053  * Used to reset the vnode fields including those that are directly accessible
2054  * as well as those which require an accessor function.
2055  *
2056  * Does not initialize:
2057  *	synchronization objects: v_lock, v_nbllock, v_cv
2058  *	v_data (since FS-nodes and vnodes point to each other and should
2059  *		be updated simultaneously)
2060  *	v_op (in case someone needs to make a VOP call on this object)
2061  */
2062 void
2063 vn_reinit(vnode_t *vp)
2064 {
2065 	vp->v_count = 1;
2066 	vp->v_vfsp = NULL;
2067 	vp->v_stream = NULL;
2068 	vp->v_vfsmountedhere = NULL;
2069 	vp->v_flag = 0;
2070 	vp->v_type = VNON;
2071 	vp->v_rdev = NODEV;
2072 
2073 	vp->v_filocks = NULL;
2074 	vp->v_shrlocks = NULL;
2075 	vp->v_pages = NULL;
2076 	vp->v_npages = 0;
2077 	vp->v_msnpages = 0;
2078 	vp->v_scanfront = NULL;
2079 	vp->v_scanback = NULL;
2080 
2081 	vp->v_locality = NULL;
2082 	vp->v_scantime = 0;
2083 	vp->v_mset = 0;
2084 	vp->v_msflags = 0;
2085 	vp->v_msnext = NULL;
2086 	vp->v_msprev = NULL;
2087 
2088 	/* Handles v_femhead, v_path, and the r/w/map counts */
2089 	vn_recycle(vp);
2090 }
2091 
2092 vnode_t *
2093 vn_alloc(int kmflag)
2094 {
2095 	vnode_t *vp;
2096 
2097 	vp = kmem_cache_alloc(vn_cache, kmflag);
2098 
2099 	if (vp != NULL) {
2100 		vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
2101 		vn_reinit(vp);
2102 	}
2103 
2104 	return (vp);
2105 }
2106 
2107 void
2108 vn_free(vnode_t *vp)
2109 {
2110 	/*
2111 	 * Some file systems call vn_free() with v_count of zero,
2112 	 * some with v_count of 1.  In any case, the value should
2113 	 * never be anything else.
2114 	 */
2115 	ASSERT((vp->v_count == 0) || (vp->v_count == 1));
2116 	if (vp->v_path != NULL) {
2117 		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
2118 		vp->v_path = NULL;
2119 	}
2120 
2121 	/* If FEM was in use, make sure everything gets cleaned up */
2122 	if (vp->v_femhead) {
2123 		/* XXX - There should be a free_femhead() that does all this */
2124 		ASSERT(vp->v_femhead->femh_list == NULL);
2125 		mutex_destroy(&vp->v_femhead->femh_lock);
2126 		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
2127 		vp->v_femhead = NULL;
2128 	}
2129 	vp->v_mpssdata = NULL;
2130 	kmem_cache_free(vn_cache, vp);
2131 }
2132 
2133 /*
2134  * vnode status changes, should define better states than 1, 0.
2135  */
2136 void
2137 vn_reclaim(vnode_t *vp)
2138 {
2139 	vfs_t   *vfsp = vp->v_vfsp;
2140 
2141 	if (vfsp == NULL ||
2142 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2143 		return;
2144 	}
2145 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_RECLAIMED);
2146 }
2147 
2148 void
2149 vn_idle(vnode_t *vp)
2150 {
2151 	vfs_t   *vfsp = vp->v_vfsp;
2152 
2153 	if (vfsp == NULL ||
2154 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2155 		return;
2156 	}
2157 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_IDLED);
2158 }
2159 void
2160 vn_exists(vnode_t *vp)
2161 {
2162 	vfs_t   *vfsp = vp->v_vfsp;
2163 
2164 	if (vfsp == NULL ||
2165 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2166 		return;
2167 	}
2168 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_EXISTS);
2169 }
2170 
2171 void
2172 vn_invalid(vnode_t *vp)
2173 {
2174 	vfs_t   *vfsp = vp->v_vfsp;
2175 
2176 	if (vfsp == NULL ||
2177 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2178 		return;
2179 	}
2180 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_DESTROYED);
2181 }
2182 
2183 /* Vnode event notification */
2184 
2185 int
2186 vnevent_support(vnode_t *vp)
2187 {
2188 	if (vp == NULL)
2189 		return (EINVAL);
2190 
2191 	return (VOP_VNEVENT(vp, VE_SUPPORT));
2192 }
2193 
2194 void
2195 vnevent_rename_src(vnode_t *vp)
2196 {
2197 	if (vp == NULL || vp->v_femhead == NULL) {
2198 		return;
2199 	}
2200 	(void) VOP_VNEVENT(vp, VE_RENAME_SRC);
2201 }
2202 
2203 void
2204 vnevent_rename_dest(vnode_t *vp)
2205 {
2206 	if (vp == NULL || vp->v_femhead == NULL) {
2207 		return;
2208 	}
2209 	(void) VOP_VNEVENT(vp, VE_RENAME_DEST);
2210 }
2211 
2212 void
2213 vnevent_remove(vnode_t *vp)
2214 {
2215 	if (vp == NULL || vp->v_femhead == NULL) {
2216 		return;
2217 	}
2218 	(void) VOP_VNEVENT(vp, VE_REMOVE);
2219 }
2220 
2221 void
2222 vnevent_rmdir(vnode_t *vp)
2223 {
2224 	if (vp == NULL || vp->v_femhead == NULL) {
2225 		return;
2226 	}
2227 	(void) VOP_VNEVENT(vp, VE_RMDIR);
2228 }
2229 
2230 /*
2231  * Vnode accessors.
2232  */
2233 
2234 int
2235 vn_is_readonly(vnode_t *vp)
2236 {
2237 	return (vp->v_vfsp->vfs_flag & VFS_RDONLY);
2238 }
2239 
2240 int
2241 vn_has_flocks(vnode_t *vp)
2242 {
2243 	return (vp->v_filocks != NULL);
2244 }
2245 
2246 int
2247 vn_has_mandatory_locks(vnode_t *vp, int mode)
2248 {
2249 	return ((vp->v_filocks != NULL) && (MANDLOCK(vp, mode)));
2250 }
2251 
2252 int
2253 vn_has_cached_data(vnode_t *vp)
2254 {
2255 	return (vp->v_pages != NULL);
2256 }
2257 
2258 /*
2259  * Return 0 if the vnode in question shouldn't be permitted into a zone via
2260  * zone_enter(2).
2261  */
2262 int
2263 vn_can_change_zones(vnode_t *vp)
2264 {
2265 	struct vfssw *vswp;
2266 	int allow = 1;
2267 	vnode_t *rvp;
2268 
2269 	if (nfs_global_client_only != 0)
2270 		return (1);
2271 
2272 	/*
2273 	 * We always want to look at the underlying vnode if there is one.
2274 	 */
2275 	if (VOP_REALVP(vp, &rvp) != 0)
2276 		rvp = vp;
2277 	/*
2278 	 * Some pseudo filesystems (including doorfs) don't actually register
2279 	 * their vfsops_t, so the following may return NULL; we happily let
2280 	 * such vnodes switch zones.
2281 	 */
2282 	vswp = vfs_getvfsswbyvfsops(vfs_getops(rvp->v_vfsp));
2283 	if (vswp != NULL) {
2284 		if (vswp->vsw_flag & VSW_NOTZONESAFE)
2285 			allow = 0;
2286 		vfs_unrefvfssw(vswp);
2287 	}
2288 	return (allow);
2289 }
2290 
2291 /*
2292  * Return nonzero if the vnode is a mount point, zero if not.
2293  */
2294 int
2295 vn_ismntpt(vnode_t *vp)
2296 {
2297 	return (vp->v_vfsmountedhere != NULL);
2298 }
2299 
2300 /* Retrieve the vfs (if any) mounted on this vnode */
2301 vfs_t *
2302 vn_mountedvfs(vnode_t *vp)
2303 {
2304 	return (vp->v_vfsmountedhere);
2305 }
2306 
2307 /*
2308  * vn_is_opened() checks whether a particular file is opened and
2309  * whether the open is for read and/or write.
2310  *
2311  * Vnode counts are only kept on regular files (v_type=VREG).
2312  */
2313 int
2314 vn_is_opened(
2315 	vnode_t *vp,
2316 	v_mode_t mode)
2317 {
2318 
2319 	ASSERT(vp != NULL);
2320 
2321 	switch (mode) {
2322 	case V_WRITE:
2323 		if (vp->v_wrcnt)
2324 			return (V_TRUE);
2325 		break;
2326 	case V_RDANDWR:
2327 		if (vp->v_rdcnt && vp->v_wrcnt)
2328 			return (V_TRUE);
2329 		break;
2330 	case V_RDORWR:
2331 		if (vp->v_rdcnt || vp->v_wrcnt)
2332 			return (V_TRUE);
2333 		break;
2334 	case V_READ:
2335 		if (vp->v_rdcnt)
2336 			return (V_TRUE);
2337 		break;
2338 	}
2339 
2340 	return (V_FALSE);
2341 }
2342 
2343 /*
2344  * vn_is_mapped() checks whether a particular file is mapped and whether
2345  * the file is mapped read and/or write.
2346  */
2347 int
2348 vn_is_mapped(
2349 	vnode_t *vp,
2350 	v_mode_t mode)
2351 {
2352 
2353 	ASSERT(vp != NULL);
2354 
2355 #if !defined(_LP64)
2356 	switch (mode) {
2357 	/*
2358 	 * The atomic_add_64_nv functions force atomicity in the
2359 	 * case of 32 bit architectures. Otherwise the 64 bit values
2360 	 * require two fetches. The value of the fields may be
2361 	 * (potentially) changed between the first fetch and the
2362 	 * second
2363 	 */
2364 	case V_WRITE:
2365 		if (atomic_add_64_nv((&(vp->v_mmap_write)), 0))
2366 			return (V_TRUE);
2367 		break;
2368 	case V_RDANDWR:
2369 		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) &&
2370 		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
2371 			return (V_TRUE);
2372 		break;
2373 	case V_RDORWR:
2374 		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) ||
2375 		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
2376 			return (V_TRUE);
2377 		break;
2378 	case V_READ:
2379 		if (atomic_add_64_nv((&(vp->v_mmap_read)), 0))
2380 			return (V_TRUE);
2381 		break;
2382 	}
2383 #else
2384 	switch (mode) {
2385 	case V_WRITE:
2386 		if (vp->v_mmap_write)
2387 			return (V_TRUE);
2388 		break;
2389 	case V_RDANDWR:
2390 		if (vp->v_mmap_read && vp->v_mmap_write)
2391 			return (V_TRUE);
2392 		break;
2393 	case V_RDORWR:
2394 		if (vp->v_mmap_read || vp->v_mmap_write)
2395 			return (V_TRUE);
2396 		break;
2397 	case V_READ:
2398 		if (vp->v_mmap_read)
2399 			return (V_TRUE);
2400 		break;
2401 	}
2402 #endif
2403 
2404 	return (V_FALSE);
2405 }
2406 
2407 /*
2408  * Set the operations vector for a vnode.
2409  *
2410  * FEM ensures that the v_femhead pointer is filled in before the
2411  * v_op pointer is changed.  This means that if the v_femhead pointer
2412  * is NULL, and the v_op field hasn't changed since before which checked
2413  * the v_femhead pointer; then our update is ok - we are not racing with
2414  * FEM.
2415  */
2416 void
2417 vn_setops(vnode_t *vp, vnodeops_t *vnodeops)
2418 {
2419 	vnodeops_t	*op;
2420 
2421 	ASSERT(vp != NULL);
2422 	ASSERT(vnodeops != NULL);
2423 
2424 	op = vp->v_op;
2425 	membar_consumer();
2426 	/*
2427 	 * If vp->v_femhead == NULL, then we'll call casptr() to do the
2428 	 * compare-and-swap on vp->v_op.  If either fails, then FEM is
2429 	 * in effect on the vnode and we need to have FEM deal with it.
2430 	 */
2431 	if (vp->v_femhead != NULL || casptr(&vp->v_op, op, vnodeops) != op) {
2432 		fem_setvnops(vp, vnodeops);
2433 	}
2434 }
2435 
2436 /*
2437  * Retrieve the operations vector for a vnode
2438  * As with vn_setops(above); make sure we aren't racing with FEM.
2439  * FEM sets the v_op to a special, internal, vnodeops that wouldn't
2440  * make sense to the callers of this routine.
2441  */
2442 vnodeops_t *
2443 vn_getops(vnode_t *vp)
2444 {
2445 	vnodeops_t	*op;
2446 
2447 	ASSERT(vp != NULL);
2448 
2449 	op = vp->v_op;
2450 	membar_consumer();
2451 	if (vp->v_femhead == NULL && op == vp->v_op) {
2452 		return (op);
2453 	} else {
2454 		return (fem_getvnops(vp));
2455 	}
2456 }
2457 
2458 /*
2459  * Returns non-zero (1) if the vnodeops matches that of the vnode.
2460  * Returns zero (0) if not.
2461  */
2462 int
2463 vn_matchops(vnode_t *vp, vnodeops_t *vnodeops)
2464 {
2465 	return (vn_getops(vp) == vnodeops);
2466 }
2467 
2468 /*
2469  * Returns non-zero (1) if the specified operation matches the
2470  * corresponding operation for that the vnode.
2471  * Returns zero (0) if not.
2472  */
2473 
2474 #define	MATCHNAME(n1, n2) (((n1)[0] == (n2)[0]) && (strcmp((n1), (n2)) == 0))
2475 
2476 int
2477 vn_matchopval(vnode_t *vp, char *vopname, fs_generic_func_p funcp)
2478 {
2479 	const fs_operation_trans_def_t *otdp;
2480 	fs_generic_func_p *loc = NULL;
2481 	vnodeops_t	*vop = vn_getops(vp);
2482 
2483 	ASSERT(vopname != NULL);
2484 
2485 	for (otdp = vn_ops_table; otdp->name != NULL; otdp++) {
2486 		if (MATCHNAME(otdp->name, vopname)) {
2487 			loc = (fs_generic_func_p *)((char *)(vop)
2488 							+ otdp->offset);
2489 			break;
2490 		}
2491 	}
2492 
2493 	return ((loc != NULL) && (*loc == funcp));
2494 }
2495 
2496 /*
2497  * fs_new_caller_id() needs to return a unique ID on a given local system.
2498  * The IDs do not need to survive across reboots.  These are primarily
2499  * used so that (FEM) monitors can detect particular callers (such as
2500  * the NFS server) to a given vnode/vfs operation.
2501  */
2502 u_longlong_t
2503 fs_new_caller_id()
2504 {
2505 	static uint64_t next_caller_id = 0LL; /* First call returns 1 */
2506 
2507 	return ((u_longlong_t)atomic_add_64_nv(&next_caller_id, 1));
2508 }
2509 
2510 /*
2511  * Given a starting vnode and a path, updates the path in the target vnode in
2512  * a safe manner.  If the vnode already has path information embedded, then the
2513  * cached path is left untouched.
2514  */
2515 
2516 size_t max_vnode_path = 4 * MAXPATHLEN;
2517 
2518 void
2519 vn_setpath(vnode_t *rootvp, struct vnode *startvp, struct vnode *vp,
2520     const char *path, size_t plen)
2521 {
2522 	char	*rpath;
2523 	vnode_t	*base;
2524 	size_t	rpathlen, rpathalloc;
2525 	int	doslash = 1;
2526 
2527 	if (*path == '/') {
2528 		base = rootvp;
2529 		path++;
2530 		plen--;
2531 	} else {
2532 		base = startvp;
2533 	}
2534 
2535 	/*
2536 	 * We cannot grab base->v_lock while we hold vp->v_lock because of
2537 	 * the potential for deadlock.
2538 	 */
2539 	mutex_enter(&base->v_lock);
2540 	if (base->v_path == NULL) {
2541 		mutex_exit(&base->v_lock);
2542 		return;
2543 	}
2544 
2545 	rpathlen = strlen(base->v_path);
2546 	rpathalloc = rpathlen + plen + 1;
2547 	/* Avoid adding a slash if there's already one there */
2548 	if (base->v_path[rpathlen-1] == '/')
2549 		doslash = 0;
2550 	else
2551 		rpathalloc++;
2552 
2553 	/*
2554 	 * We don't want to call kmem_alloc(KM_SLEEP) with kernel locks held,
2555 	 * so we must do this dance.  If, by chance, something changes the path,
2556 	 * just give up since there is no real harm.
2557 	 */
2558 	mutex_exit(&base->v_lock);
2559 
2560 	/* Paths should stay within reason */
2561 	if (rpathalloc > max_vnode_path)
2562 		return;
2563 
2564 	rpath = kmem_alloc(rpathalloc, KM_SLEEP);
2565 
2566 	mutex_enter(&base->v_lock);
2567 	if (base->v_path == NULL || strlen(base->v_path) != rpathlen) {
2568 		mutex_exit(&base->v_lock);
2569 		kmem_free(rpath, rpathalloc);
2570 		return;
2571 	}
2572 	bcopy(base->v_path, rpath, rpathlen);
2573 	mutex_exit(&base->v_lock);
2574 
2575 	if (doslash)
2576 		rpath[rpathlen++] = '/';
2577 	bcopy(path, rpath + rpathlen, plen);
2578 	rpath[rpathlen + plen] = '\0';
2579 
2580 	mutex_enter(&vp->v_lock);
2581 	if (vp->v_path != NULL) {
2582 		mutex_exit(&vp->v_lock);
2583 		kmem_free(rpath, rpathalloc);
2584 	} else {
2585 		vp->v_path = rpath;
2586 		mutex_exit(&vp->v_lock);
2587 	}
2588 }
2589 
2590 /*
2591  * Sets the path to the vnode to be the given string, regardless of current
2592  * context.  The string must be a complete path from rootdir.  This is only used
2593  * by fsop_root() for setting the path based on the mountpoint.
2594  */
2595 void
2596 vn_setpath_str(struct vnode *vp, const char *str, size_t len)
2597 {
2598 	char *buf = kmem_alloc(len + 1, KM_SLEEP);
2599 
2600 	mutex_enter(&vp->v_lock);
2601 	if (vp->v_path != NULL) {
2602 		mutex_exit(&vp->v_lock);
2603 		kmem_free(buf, len + 1);
2604 		return;
2605 	}
2606 
2607 	vp->v_path = buf;
2608 	bcopy(str, vp->v_path, len);
2609 	vp->v_path[len] = '\0';
2610 
2611 	mutex_exit(&vp->v_lock);
2612 }
2613 
2614 /*
2615  * Similar to vn_setpath_str(), this function sets the path of the destination
2616  * vnode to the be the same as the source vnode.
2617  */
2618 void
2619 vn_copypath(struct vnode *src, struct vnode *dst)
2620 {
2621 	char *buf;
2622 	int alloc;
2623 
2624 	mutex_enter(&src->v_lock);
2625 	if (src->v_path == NULL) {
2626 		mutex_exit(&src->v_lock);
2627 		return;
2628 	}
2629 	alloc = strlen(src->v_path) + 1;
2630 
2631 	/* avoid kmem_alloc() with lock held */
2632 	mutex_exit(&src->v_lock);
2633 	buf = kmem_alloc(alloc, KM_SLEEP);
2634 	mutex_enter(&src->v_lock);
2635 	if (src->v_path == NULL || strlen(src->v_path) + 1 != alloc) {
2636 		mutex_exit(&src->v_lock);
2637 		kmem_free(buf, alloc);
2638 		return;
2639 	}
2640 	bcopy(src->v_path, buf, alloc);
2641 	mutex_exit(&src->v_lock);
2642 
2643 	mutex_enter(&dst->v_lock);
2644 	if (dst->v_path != NULL) {
2645 		mutex_exit(&dst->v_lock);
2646 		kmem_free(buf, alloc);
2647 		return;
2648 	}
2649 	dst->v_path = buf;
2650 	mutex_exit(&dst->v_lock);
2651 }
2652 
2653 /*
2654  * XXX Private interface for segvn routines that handle vnode
2655  * large page segments.
2656  *
2657  * return 1 if vp's file system VOP_PAGEIO() implementation
2658  * can be safely used instead of VOP_GETPAGE() for handling
2659  * pagefaults against regular non swap files. VOP_PAGEIO()
2660  * interface is considered safe here if its implementation
2661  * is very close to VOP_GETPAGE() implementation.
2662  * e.g. It zero's out the part of the page beyond EOF. Doesn't
2663  * panic if there're file holes but instead returns an error.
2664  * Doesn't assume file won't be changed by user writes, etc.
2665  *
2666  * return 0 otherwise.
2667  *
2668  * For now allow segvn to only use VOP_PAGEIO() with ufs and nfs.
2669  */
2670 int
2671 vn_vmpss_usepageio(vnode_t *vp)
2672 {
2673 	vfs_t   *vfsp = vp->v_vfsp;
2674 	char *fsname = vfssw[vfsp->vfs_fstype].vsw_name;
2675 	char *pageio_ok_fss[] = {"ufs", "nfs", NULL};
2676 	char **fsok = pageio_ok_fss;
2677 
2678 	if (fsname == NULL) {
2679 		return (0);
2680 	}
2681 
2682 	for (; *fsok; fsok++) {
2683 		if (strcmp(*fsok, fsname) == 0) {
2684 			return (1);
2685 		}
2686 	}
2687 	return (0);
2688 }
2689 
2690 /* VOP_XXX() macros call the corresponding fop_xxx() function */
2691 
2692 int
2693 fop_open(
2694 	vnode_t **vpp,
2695 	int mode,
2696 	cred_t *cr)
2697 {
2698 	int ret;
2699 	vnode_t *vp = *vpp;
2700 
2701 	VN_HOLD(vp);
2702 	/*
2703 	 * Adding to the vnode counts before calling open
2704 	 * avoids the need for a mutex. It circumvents a race
2705 	 * condition where a query made on the vnode counts results in a
2706 	 * false negative. The inquirer goes away believing the file is
2707 	 * not open when there is an open on the file already under way.
2708 	 *
2709 	 * The counts are meant to prevent NFS from granting a delegation
2710 	 * when it would be dangerous to do so.
2711 	 *
2712 	 * The vnode counts are only kept on regular files
2713 	 */
2714 	if ((*vpp)->v_type == VREG) {
2715 		if (mode & FREAD)
2716 			atomic_add_32(&((*vpp)->v_rdcnt), 1);
2717 		if (mode & FWRITE)
2718 			atomic_add_32(&((*vpp)->v_wrcnt), 1);
2719 	}
2720 
2721 	ret = (*(*(vpp))->v_op->vop_open)(vpp, mode, cr);
2722 
2723 	if (ret) {
2724 		/*
2725 		 * Use the saved vp just in case the vnode ptr got trashed
2726 		 * by the error.
2727 		 */
2728 		VOPSTATS_UPDATE(vp, open);
2729 		if ((vp->v_type == VREG) && (mode & FREAD))
2730 			atomic_add_32(&(vp->v_rdcnt), -1);
2731 		if ((vp->v_type == VREG) && (mode & FWRITE))
2732 			atomic_add_32(&(vp->v_wrcnt), -1);
2733 	} else {
2734 		/*
2735 		 * Some filesystems will return a different vnode,
2736 		 * but the same path was still used to open it.
2737 		 * So if we do change the vnode and need to
2738 		 * copy over the path, do so here, rather than special
2739 		 * casing each filesystem. Adjust the vnode counts to
2740 		 * reflect the vnode switch.
2741 		 */
2742 		VOPSTATS_UPDATE(*vpp, open);
2743 		if (*vpp != vp && *vpp != NULL) {
2744 			vn_copypath(vp, *vpp);
2745 			if (((*vpp)->v_type == VREG) && (mode & FREAD))
2746 				atomic_add_32(&((*vpp)->v_rdcnt), 1);
2747 			if ((vp->v_type == VREG) && (mode & FREAD))
2748 				atomic_add_32(&(vp->v_rdcnt), -1);
2749 			if (((*vpp)->v_type == VREG) && (mode & FWRITE))
2750 				atomic_add_32(&((*vpp)->v_wrcnt), 1);
2751 			if ((vp->v_type == VREG) && (mode & FWRITE))
2752 				atomic_add_32(&(vp->v_wrcnt), -1);
2753 		}
2754 	}
2755 	VN_RELE(vp);
2756 	return (ret);
2757 }
2758 
2759 int
2760 fop_close(
2761 	vnode_t *vp,
2762 	int flag,
2763 	int count,
2764 	offset_t offset,
2765 	cred_t *cr)
2766 {
2767 	int err;
2768 
2769 	err = (*(vp)->v_op->vop_close)(vp, flag, count, offset, cr);
2770 	VOPSTATS_UPDATE(vp, close);
2771 	/*
2772 	 * Check passed in count to handle possible dups. Vnode counts are only
2773 	 * kept on regular files
2774 	 */
2775 	if ((vp->v_type == VREG) && (count == 1))  {
2776 		if (flag & FREAD) {
2777 			ASSERT(vp->v_rdcnt > 0);
2778 			atomic_add_32(&(vp->v_rdcnt), -1);
2779 		}
2780 		if (flag & FWRITE) {
2781 			ASSERT(vp->v_wrcnt > 0);
2782 			atomic_add_32(&(vp->v_wrcnt), -1);
2783 		}
2784 	}
2785 	return (err);
2786 }
2787 
2788 int
2789 fop_read(
2790 	vnode_t *vp,
2791 	uio_t *uiop,
2792 	int ioflag,
2793 	cred_t *cr,
2794 	struct caller_context *ct)
2795 {
2796 	int	err;
2797 	ssize_t	resid_start = uiop->uio_resid;
2798 
2799 	err = (*(vp)->v_op->vop_read)(vp, uiop, ioflag, cr, ct);
2800 	VOPSTATS_UPDATE_IO(vp, read,
2801 	    read_bytes, (resid_start - uiop->uio_resid));
2802 	return (err);
2803 }
2804 
2805 int
2806 fop_write(
2807 	vnode_t *vp,
2808 	uio_t *uiop,
2809 	int ioflag,
2810 	cred_t *cr,
2811 	struct caller_context *ct)
2812 {
2813 	int	err;
2814 	ssize_t	resid_start = uiop->uio_resid;
2815 
2816 	err = (*(vp)->v_op->vop_write)(vp, uiop, ioflag, cr, ct);
2817 	VOPSTATS_UPDATE_IO(vp, write,
2818 	    write_bytes, (resid_start - uiop->uio_resid));
2819 	return (err);
2820 }
2821 
2822 int
2823 fop_ioctl(
2824 	vnode_t *vp,
2825 	int cmd,
2826 	intptr_t arg,
2827 	int flag,
2828 	cred_t *cr,
2829 	int *rvalp)
2830 {
2831 	int	err;
2832 
2833 	err = (*(vp)->v_op->vop_ioctl)(vp, cmd, arg, flag, cr, rvalp);
2834 	VOPSTATS_UPDATE(vp, ioctl);
2835 	return (err);
2836 }
2837 
2838 int
2839 fop_setfl(
2840 	vnode_t *vp,
2841 	int oflags,
2842 	int nflags,
2843 	cred_t *cr)
2844 {
2845 	int	err;
2846 
2847 	err = (*(vp)->v_op->vop_setfl)(vp, oflags, nflags, cr);
2848 	VOPSTATS_UPDATE(vp, setfl);
2849 	return (err);
2850 }
2851 
2852 int
2853 fop_getattr(
2854 	vnode_t *vp,
2855 	vattr_t *vap,
2856 	int flags,
2857 	cred_t *cr)
2858 {
2859 	int	err;
2860 
2861 	err = (*(vp)->v_op->vop_getattr)(vp, vap, flags, cr);
2862 	VOPSTATS_UPDATE(vp, getattr);
2863 	return (err);
2864 }
2865 
2866 int
2867 fop_setattr(
2868 	vnode_t *vp,
2869 	vattr_t *vap,
2870 	int flags,
2871 	cred_t *cr,
2872 	caller_context_t *ct)
2873 {
2874 	int	err;
2875 
2876 	err = (*(vp)->v_op->vop_setattr)(vp, vap, flags, cr, ct);
2877 	VOPSTATS_UPDATE(vp, setattr);
2878 	return (err);
2879 }
2880 
2881 int
2882 fop_access(
2883 	vnode_t *vp,
2884 	int mode,
2885 	int flags,
2886 	cred_t *cr)
2887 {
2888 	int	err;
2889 
2890 	err = (*(vp)->v_op->vop_access)(vp, mode, flags, cr);
2891 	VOPSTATS_UPDATE(vp, access);
2892 	return (err);
2893 }
2894 
2895 int
2896 fop_lookup(
2897 	vnode_t *dvp,
2898 	char *nm,
2899 	vnode_t **vpp,
2900 	pathname_t *pnp,
2901 	int flags,
2902 	vnode_t *rdir,
2903 	cred_t *cr)
2904 {
2905 	int ret;
2906 
2907 	ret = (*(dvp)->v_op->vop_lookup)(dvp, nm, vpp, pnp, flags, rdir, cr);
2908 	if (ret == 0 && *vpp) {
2909 		VOPSTATS_UPDATE(*vpp, lookup);
2910 		if ((*vpp)->v_path == NULL) {
2911 			vn_setpath(rootdir, dvp, *vpp, nm, strlen(nm));
2912 		}
2913 	}
2914 
2915 	return (ret);
2916 }
2917 
2918 int
2919 fop_create(
2920 	vnode_t *dvp,
2921 	char *name,
2922 	vattr_t *vap,
2923 	vcexcl_t excl,
2924 	int mode,
2925 	vnode_t **vpp,
2926 	cred_t *cr,
2927 	int flag)
2928 {
2929 	int ret;
2930 
2931 	ret = (*(dvp)->v_op->vop_create)
2932 				(dvp, name, vap, excl, mode, vpp, cr, flag);
2933 	if (ret == 0 && *vpp) {
2934 		VOPSTATS_UPDATE(*vpp, create);
2935 		if ((*vpp)->v_path == NULL) {
2936 			vn_setpath(rootdir, dvp, *vpp, name, strlen(name));
2937 		}
2938 	}
2939 
2940 	return (ret);
2941 }
2942 
2943 int
2944 fop_remove(
2945 	vnode_t *dvp,
2946 	char *nm,
2947 	cred_t *cr)
2948 {
2949 	int	err;
2950 
2951 	err = (*(dvp)->v_op->vop_remove)(dvp, nm, cr);
2952 	VOPSTATS_UPDATE(dvp, remove);
2953 	return (err);
2954 }
2955 
2956 int
2957 fop_link(
2958 	vnode_t *tdvp,
2959 	vnode_t *svp,
2960 	char *tnm,
2961 	cred_t *cr)
2962 {
2963 	int	err;
2964 
2965 	err = (*(tdvp)->v_op->vop_link)(tdvp, svp, tnm, cr);
2966 	VOPSTATS_UPDATE(tdvp, link);
2967 	return (err);
2968 }
2969 
2970 int
2971 fop_rename(
2972 	vnode_t *sdvp,
2973 	char *snm,
2974 	vnode_t *tdvp,
2975 	char *tnm,
2976 	cred_t *cr)
2977 {
2978 	int	err;
2979 
2980 	err = (*(sdvp)->v_op->vop_rename)(sdvp, snm, tdvp, tnm, cr);
2981 	VOPSTATS_UPDATE(sdvp, rename);
2982 	return (err);
2983 }
2984 
2985 int
2986 fop_mkdir(
2987 	vnode_t *dvp,
2988 	char *dirname,
2989 	vattr_t *vap,
2990 	vnode_t **vpp,
2991 	cred_t *cr)
2992 {
2993 	int ret;
2994 
2995 	ret = (*(dvp)->v_op->vop_mkdir)(dvp, dirname, vap, vpp, cr);
2996 	if (ret == 0 && *vpp) {
2997 		VOPSTATS_UPDATE(*vpp, mkdir);
2998 		if ((*vpp)->v_path == NULL) {
2999 			vn_setpath(rootdir, dvp, *vpp, dirname,
3000 			    strlen(dirname));
3001 		}
3002 	}
3003 
3004 	return (ret);
3005 }
3006 
3007 int
3008 fop_rmdir(
3009 	vnode_t *dvp,
3010 	char *nm,
3011 	vnode_t *cdir,
3012 	cred_t *cr)
3013 {
3014 	int	err;
3015 
3016 	err = (*(dvp)->v_op->vop_rmdir)(dvp, nm, cdir, cr);
3017 	VOPSTATS_UPDATE(dvp, rmdir);
3018 	return (err);
3019 }
3020 
3021 int
3022 fop_readdir(
3023 	vnode_t *vp,
3024 	uio_t *uiop,
3025 	cred_t *cr,
3026 	int *eofp)
3027 {
3028 	int	err;
3029 	ssize_t	resid_start = uiop->uio_resid;
3030 
3031 	err = (*(vp)->v_op->vop_readdir)(vp, uiop, cr, eofp);
3032 	VOPSTATS_UPDATE_IO(vp, readdir,
3033 	    readdir_bytes, (resid_start - uiop->uio_resid));
3034 	return (err);
3035 }
3036 
3037 int
3038 fop_symlink(
3039 	vnode_t *dvp,
3040 	char *linkname,
3041 	vattr_t *vap,
3042 	char *target,
3043 	cred_t *cr)
3044 {
3045 	int	err;
3046 
3047 	err = (*(dvp)->v_op->vop_symlink) (dvp, linkname, vap, target, cr);
3048 	VOPSTATS_UPDATE(dvp, symlink);
3049 	return (err);
3050 }
3051 
3052 int
3053 fop_readlink(
3054 	vnode_t *vp,
3055 	uio_t *uiop,
3056 	cred_t *cr)
3057 {
3058 	int	err;
3059 
3060 	err = (*(vp)->v_op->vop_readlink)(vp, uiop, cr);
3061 	VOPSTATS_UPDATE(vp, readlink);
3062 	return (err);
3063 }
3064 
3065 int
3066 fop_fsync(
3067 	vnode_t *vp,
3068 	int syncflag,
3069 	cred_t *cr)
3070 {
3071 	int	err;
3072 
3073 	err = (*(vp)->v_op->vop_fsync)(vp, syncflag, cr);
3074 	VOPSTATS_UPDATE(vp, fsync);
3075 	return (err);
3076 }
3077 
3078 void
3079 fop_inactive(
3080 	vnode_t *vp,
3081 	cred_t *cr)
3082 {
3083 	/* Need to update stats before vop call since we may lose the vnode */
3084 	VOPSTATS_UPDATE(vp, inactive);
3085 	(*(vp)->v_op->vop_inactive)(vp, cr);
3086 }
3087 
3088 int
3089 fop_fid(
3090 	vnode_t *vp,
3091 	fid_t *fidp)
3092 {
3093 	int	err;
3094 
3095 	err = (*(vp)->v_op->vop_fid)(vp, fidp);
3096 	VOPSTATS_UPDATE(vp, fid);
3097 	return (err);
3098 }
3099 
3100 int
3101 fop_rwlock(
3102 	vnode_t *vp,
3103 	int write_lock,
3104 	caller_context_t *ct)
3105 {
3106 	int	ret;
3107 
3108 	ret = ((*(vp)->v_op->vop_rwlock)(vp, write_lock, ct));
3109 	VOPSTATS_UPDATE(vp, rwlock);
3110 	return (ret);
3111 }
3112 
3113 void
3114 fop_rwunlock(
3115 	vnode_t *vp,
3116 	int write_lock,
3117 	caller_context_t *ct)
3118 {
3119 	(*(vp)->v_op->vop_rwunlock)(vp, write_lock, ct);
3120 	VOPSTATS_UPDATE(vp, rwunlock);
3121 }
3122 
3123 int
3124 fop_seek(
3125 	vnode_t *vp,
3126 	offset_t ooff,
3127 	offset_t *noffp)
3128 {
3129 	int	err;
3130 
3131 	err = (*(vp)->v_op->vop_seek)(vp, ooff, noffp);
3132 	VOPSTATS_UPDATE(vp, seek);
3133 	return (err);
3134 }
3135 
3136 int
3137 fop_cmp(
3138 	vnode_t *vp1,
3139 	vnode_t *vp2)
3140 {
3141 	int	err;
3142 
3143 	err = (*(vp1)->v_op->vop_cmp)(vp1, vp2);
3144 	VOPSTATS_UPDATE(vp1, cmp);
3145 	return (err);
3146 }
3147 
3148 int
3149 fop_frlock(
3150 	vnode_t *vp,
3151 	int cmd,
3152 	flock64_t *bfp,
3153 	int flag,
3154 	offset_t offset,
3155 	struct flk_callback *flk_cbp,
3156 	cred_t *cr)
3157 {
3158 	int	err;
3159 
3160 	err = (*(vp)->v_op->vop_frlock)
3161 				(vp, cmd, bfp, flag, offset, flk_cbp, cr);
3162 	VOPSTATS_UPDATE(vp, frlock);
3163 	return (err);
3164 }
3165 
3166 int
3167 fop_space(
3168 	vnode_t *vp,
3169 	int cmd,
3170 	flock64_t *bfp,
3171 	int flag,
3172 	offset_t offset,
3173 	cred_t *cr,
3174 	caller_context_t *ct)
3175 {
3176 	int	err;
3177 
3178 	err = (*(vp)->v_op->vop_space)(vp, cmd, bfp, flag, offset, cr, ct);
3179 	VOPSTATS_UPDATE(vp, space);
3180 	return (err);
3181 }
3182 
3183 int
3184 fop_realvp(
3185 	vnode_t *vp,
3186 	vnode_t **vpp)
3187 {
3188 	int	err;
3189 
3190 	err = (*(vp)->v_op->vop_realvp)(vp, vpp);
3191 	VOPSTATS_UPDATE(vp, realvp);
3192 	return (err);
3193 }
3194 
3195 int
3196 fop_getpage(
3197 	vnode_t *vp,
3198 	offset_t off,
3199 	size_t len,
3200 	uint_t *protp,
3201 	page_t **plarr,
3202 	size_t plsz,
3203 	struct seg *seg,
3204 	caddr_t addr,
3205 	enum seg_rw rw,
3206 	cred_t *cr)
3207 {
3208 	int	err;
3209 
3210 	err = (*(vp)->v_op->vop_getpage)
3211 			(vp, off, len, protp, plarr, plsz, seg, addr, rw, cr);
3212 	VOPSTATS_UPDATE(vp, getpage);
3213 	return (err);
3214 }
3215 
3216 int
3217 fop_putpage(
3218 	vnode_t *vp,
3219 	offset_t off,
3220 	size_t len,
3221 	int flags,
3222 	cred_t *cr)
3223 {
3224 	int	err;
3225 
3226 	err = (*(vp)->v_op->vop_putpage)(vp, off, len, flags, cr);
3227 	VOPSTATS_UPDATE(vp, putpage);
3228 	return (err);
3229 }
3230 
3231 int
3232 fop_map(
3233 	vnode_t *vp,
3234 	offset_t off,
3235 	struct as *as,
3236 	caddr_t *addrp,
3237 	size_t len,
3238 	uchar_t prot,
3239 	uchar_t maxprot,
3240 	uint_t flags,
3241 	cred_t *cr)
3242 {
3243 	int	err;
3244 
3245 	err = (*(vp)->v_op->vop_map)
3246 			(vp, off, as, addrp, len, prot, maxprot, flags, cr);
3247 	VOPSTATS_UPDATE(vp, map);
3248 	return (err);
3249 }
3250 
3251 int
3252 fop_addmap(
3253 	vnode_t *vp,
3254 	offset_t off,
3255 	struct as *as,
3256 	caddr_t addr,
3257 	size_t len,
3258 	uchar_t prot,
3259 	uchar_t maxprot,
3260 	uint_t flags,
3261 	cred_t *cr)
3262 {
3263 	int error;
3264 	u_longlong_t delta;
3265 
3266 	error = (*(vp)->v_op->vop_addmap)
3267 			(vp, off, as, addr, len, prot, maxprot, flags, cr);
3268 
3269 	if ((!error) && (vp->v_type == VREG)) {
3270 		delta = (u_longlong_t)btopr(len);
3271 		/*
3272 		 * If file is declared MAP_PRIVATE, it can't be written back
3273 		 * even if open for write. Handle as read.
3274 		 */
3275 		if (flags & MAP_PRIVATE) {
3276 			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3277 				(int64_t)delta);
3278 		} else {
3279 			/*
3280 			 * atomic_add_64 forces the fetch of a 64 bit value to
3281 			 * be atomic on 32 bit machines
3282 			 */
3283 			if (maxprot & PROT_WRITE)
3284 				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
3285 					(int64_t)delta);
3286 			if (maxprot & PROT_READ)
3287 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3288 					(int64_t)delta);
3289 			if (maxprot & PROT_EXEC)
3290 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3291 					(int64_t)delta);
3292 		}
3293 	}
3294 	VOPSTATS_UPDATE(vp, addmap);
3295 	return (error);
3296 }
3297 
3298 int
3299 fop_delmap(
3300 	vnode_t *vp,
3301 	offset_t off,
3302 	struct as *as,
3303 	caddr_t addr,
3304 	size_t len,
3305 	uint_t prot,
3306 	uint_t maxprot,
3307 	uint_t flags,
3308 	cred_t *cr)
3309 {
3310 	int error;
3311 	u_longlong_t delta;
3312 	error = (*(vp)->v_op->vop_delmap)
3313 		(vp, off, as, addr, len, prot, maxprot, flags, cr);
3314 
3315 	/*
3316 	 * NFS calls into delmap twice, the first time
3317 	 * it simply establishes a callback mechanism and returns EAGAIN
3318 	 * while the real work is being done upon the second invocation.
3319 	 * We have to detect this here and only decrement the counts upon
3320 	 * the second delmap request.
3321 	 */
3322 	if ((error != EAGAIN) && (vp->v_type == VREG)) {
3323 
3324 		delta = (u_longlong_t)btopr(len);
3325 
3326 		if (flags & MAP_PRIVATE) {
3327 			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3328 				(int64_t)(-delta));
3329 		} else {
3330 			/*
3331 			 * atomic_add_64 forces the fetch of a 64 bit value
3332 			 * to be atomic on 32 bit machines
3333 			 */
3334 			if (maxprot & PROT_WRITE)
3335 				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
3336 					(int64_t)(-delta));
3337 			if (maxprot & PROT_READ)
3338 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3339 					(int64_t)(-delta));
3340 			if (maxprot & PROT_EXEC)
3341 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3342 					(int64_t)(-delta));
3343 		}
3344 	}
3345 	VOPSTATS_UPDATE(vp, delmap);
3346 	return (error);
3347 }
3348 
3349 
3350 int
3351 fop_poll(
3352 	vnode_t *vp,
3353 	short events,
3354 	int anyyet,
3355 	short *reventsp,
3356 	struct pollhead **phpp)
3357 {
3358 	int	err;
3359 
3360 	err = (*(vp)->v_op->vop_poll)(vp, events, anyyet, reventsp, phpp);
3361 	VOPSTATS_UPDATE(vp, poll);
3362 	return (err);
3363 }
3364 
3365 int
3366 fop_dump(
3367 	vnode_t *vp,
3368 	caddr_t addr,
3369 	int lbdn,
3370 	int dblks)
3371 {
3372 	int	err;
3373 
3374 	err = (*(vp)->v_op->vop_dump)(vp, addr, lbdn, dblks);
3375 	VOPSTATS_UPDATE(vp, dump);
3376 	return (err);
3377 }
3378 
3379 int
3380 fop_pathconf(
3381 	vnode_t *vp,
3382 	int cmd,
3383 	ulong_t *valp,
3384 	cred_t *cr)
3385 {
3386 	int	err;
3387 
3388 	err = (*(vp)->v_op->vop_pathconf)(vp, cmd, valp, cr);
3389 	VOPSTATS_UPDATE(vp, pathconf);
3390 	return (err);
3391 }
3392 
3393 int
3394 fop_pageio(
3395 	vnode_t *vp,
3396 	struct page *pp,
3397 	u_offset_t io_off,
3398 	size_t io_len,
3399 	int flags,
3400 	cred_t *cr)
3401 {
3402 	int	err;
3403 
3404 	err = (*(vp)->v_op->vop_pageio)(vp, pp, io_off, io_len, flags, cr);
3405 	VOPSTATS_UPDATE(vp, pageio);
3406 	return (err);
3407 }
3408 
3409 int
3410 fop_dumpctl(
3411 	vnode_t *vp,
3412 	int action,
3413 	int *blkp)
3414 {
3415 	int	err;
3416 	err = (*(vp)->v_op->vop_dumpctl)(vp, action, blkp);
3417 	VOPSTATS_UPDATE(vp, dumpctl);
3418 	return (err);
3419 }
3420 
3421 void
3422 fop_dispose(
3423 	vnode_t *vp,
3424 	page_t *pp,
3425 	int flag,
3426 	int dn,
3427 	cred_t *cr)
3428 {
3429 	/* Must do stats first since it's possible to lose the vnode */
3430 	VOPSTATS_UPDATE(vp, dispose);
3431 	(*(vp)->v_op->vop_dispose)(vp, pp, flag, dn, cr);
3432 }
3433 
3434 int
3435 fop_setsecattr(
3436 	vnode_t *vp,
3437 	vsecattr_t *vsap,
3438 	int flag,
3439 	cred_t *cr)
3440 {
3441 	int	err;
3442 
3443 	err = (*(vp)->v_op->vop_setsecattr) (vp, vsap, flag, cr);
3444 	VOPSTATS_UPDATE(vp, setsecattr);
3445 	return (err);
3446 }
3447 
3448 int
3449 fop_getsecattr(
3450 	vnode_t *vp,
3451 	vsecattr_t *vsap,
3452 	int flag,
3453 	cred_t *cr)
3454 {
3455 	int	err;
3456 
3457 	err = (*(vp)->v_op->vop_getsecattr) (vp, vsap, flag, cr);
3458 	VOPSTATS_UPDATE(vp, getsecattr);
3459 	return (err);
3460 }
3461 
3462 int
3463 fop_shrlock(
3464 	vnode_t *vp,
3465 	int cmd,
3466 	struct shrlock *shr,
3467 	int flag,
3468 	cred_t *cr)
3469 {
3470 	int	err;
3471 
3472 	err = (*(vp)->v_op->vop_shrlock)(vp, cmd, shr, flag, cr);
3473 	VOPSTATS_UPDATE(vp, shrlock);
3474 	return (err);
3475 }
3476 
3477 int
3478 fop_vnevent(vnode_t *vp, vnevent_t vnevent)
3479 {
3480 	int	err;
3481 
3482 	err = (*(vp)->v_op->vop_vnevent)(vp, vnevent);
3483 	VOPSTATS_UPDATE(vp, vnevent);
3484 	return (err);
3485 }
3486