xref: /titanic_41/usr/src/uts/common/fs/vnode.c (revision 418e2f3050b6a419bd7c37e2ed3d8dd99b7cc261)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
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 #include <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/t_lock.h>
42 #include <sys/errno.h>
43 #include <sys/cred.h>
44 #include <sys/user.h>
45 #include <sys/uio.h>
46 #include <sys/file.h>
47 #include <sys/pathname.h>
48 #include <sys/vfs.h>
49 #include <sys/vfs_opreg.h>
50 #include <sys/vnode.h>
51 #include <sys/rwstlock.h>
52 #include <sys/fem.h>
53 #include <sys/stat.h>
54 #include <sys/mode.h>
55 #include <sys/conf.h>
56 #include <sys/sysmacros.h>
57 #include <sys/cmn_err.h>
58 #include <sys/systm.h>
59 #include <sys/kmem.h>
60 #include <sys/debug.h>
61 #include <c2/audit.h>
62 #include <sys/acl.h>
63 #include <sys/nbmlock.h>
64 #include <sys/fcntl.h>
65 #include <fs/fs_subr.h>
66 #include <sys/taskq.h>
67 #include <fs/fs_reparse.h>
68 
69 /* Determine if this vnode is a file that is read-only */
70 #define	ISROFILE(vp)	\
71 	((vp)->v_type != VCHR && (vp)->v_type != VBLK && \
72 	    (vp)->v_type != VFIFO && vn_is_readonly(vp))
73 
74 /* Tunable via /etc/system; used only by admin/install */
75 int nfs_global_client_only;
76 
77 /*
78  * Array of vopstats_t for per-FS-type vopstats.  This array has the same
79  * number of entries as and parallel to the vfssw table.  (Arguably, it could
80  * be part of the vfssw table.)  Once it's initialized, it's accessed using
81  * the same fstype index that is used to index into the vfssw table.
82  */
83 vopstats_t **vopstats_fstype;
84 
85 /* vopstats initialization template used for fast initialization via bcopy() */
86 static vopstats_t *vs_templatep;
87 
88 /* Kmem cache handle for vsk_anchor_t allocations */
89 kmem_cache_t *vsk_anchor_cache;
90 
91 /* file events cleanup routine */
92 extern void free_fopdata(vnode_t *);
93 
94 /*
95  * Root of AVL tree for the kstats associated with vopstats.  Lock protects
96  * updates to vsktat_tree.
97  */
98 avl_tree_t	vskstat_tree;
99 kmutex_t	vskstat_tree_lock;
100 
101 /* Global variable which enables/disables the vopstats collection */
102 int vopstats_enabled = 1;
103 
104 /*
105  * forward declarations for internal vnode specific data (vsd)
106  */
107 static void *vsd_realloc(void *, size_t, size_t);
108 
109 /*
110  * forward declarations for reparse point functions
111  */
112 static int fs_reparse_mark(char *target, vattr_t *vap, xvattr_t *xvattr);
113 
114 /*
115  * VSD -- VNODE SPECIFIC DATA
116  * The v_data pointer is typically used by a file system to store a
117  * pointer to the file system's private node (e.g. ufs inode, nfs rnode).
118  * However, there are times when additional project private data needs
119  * to be stored separately from the data (node) pointed to by v_data.
120  * This additional data could be stored by the file system itself or
121  * by a completely different kernel entity.  VSD provides a way for
122  * callers to obtain a key and store a pointer to private data associated
123  * with a vnode.
124  *
125  * Callers are responsible for protecting the vsd by holding v_vsd_lock
126  * for calls to vsd_set() and vsd_get().
127  */
128 
129 /*
130  * vsd_lock protects:
131  *   vsd_nkeys - creation and deletion of vsd keys
132  *   vsd_list - insertion and deletion of vsd_node in the vsd_list
133  *   vsd_destructor - adding and removing destructors to the list
134  */
135 static kmutex_t		vsd_lock;
136 static uint_t		vsd_nkeys;	 /* size of destructor array */
137 /* list of vsd_node's */
138 static list_t *vsd_list = NULL;
139 /* per-key destructor funcs */
140 static void 		(**vsd_destructor)(void *);
141 
142 /*
143  * The following is the common set of actions needed to update the
144  * vopstats structure from a vnode op.  Both VOPSTATS_UPDATE() and
145  * VOPSTATS_UPDATE_IO() do almost the same thing, except for the
146  * recording of the bytes transferred.  Since the code is similar
147  * but small, it is nearly a duplicate.  Consequently any changes
148  * to one may need to be reflected in the other.
149  * Rundown of the variables:
150  * vp - Pointer to the vnode
151  * counter - Partial name structure member to update in vopstats for counts
152  * bytecounter - Partial name structure member to update in vopstats for bytes
153  * bytesval - Value to update in vopstats for bytes
154  * fstype - Index into vsanchor_fstype[], same as index into vfssw[]
155  * vsp - Pointer to vopstats structure (either in vfs or vsanchor_fstype[i])
156  */
157 
158 #define	VOPSTATS_UPDATE(vp, counter) {					\
159 	vfs_t *vfsp = (vp)->v_vfsp;					\
160 	if (vfsp && vfsp->vfs_implp &&					\
161 	    (vfsp->vfs_flag & VFS_STATS) && (vp)->v_type != VBAD) {	\
162 		vopstats_t *vsp = &vfsp->vfs_vopstats;			\
163 		uint64_t *stataddr = &(vsp->n##counter.value.ui64);	\
164 		extern void __dtrace_probe___fsinfo_##counter(vnode_t *, \
165 		    size_t, uint64_t *);				\
166 		__dtrace_probe___fsinfo_##counter(vp, 0, stataddr);	\
167 		(*stataddr)++;						\
168 		if ((vsp = vfsp->vfs_fstypevsp) != NULL) {		\
169 			vsp->n##counter.value.ui64++;			\
170 		}							\
171 	}								\
172 }
173 
174 #define	VOPSTATS_UPDATE_IO(vp, counter, bytecounter, bytesval) {	\
175 	vfs_t *vfsp = (vp)->v_vfsp;					\
176 	if (vfsp && vfsp->vfs_implp &&					\
177 	    (vfsp->vfs_flag & VFS_STATS) && (vp)->v_type != VBAD) {	\
178 		vopstats_t *vsp = &vfsp->vfs_vopstats;			\
179 		uint64_t *stataddr = &(vsp->n##counter.value.ui64);	\
180 		extern void __dtrace_probe___fsinfo_##counter(vnode_t *, \
181 		    size_t, uint64_t *);				\
182 		__dtrace_probe___fsinfo_##counter(vp, bytesval, stataddr); \
183 		(*stataddr)++;						\
184 		vsp->bytecounter.value.ui64 += bytesval;		\
185 		if ((vsp = vfsp->vfs_fstypevsp) != NULL) {		\
186 			vsp->n##counter.value.ui64++;			\
187 			vsp->bytecounter.value.ui64 += bytesval;	\
188 		}							\
189 	}								\
190 }
191 
192 /*
193  * If the filesystem does not support XIDs map credential
194  * If the vfsp is NULL, perhaps we should also map?
195  */
196 #define	VOPXID_MAP_CR(vp, cr)	{					\
197 	vfs_t *vfsp = (vp)->v_vfsp;					\
198 	if (vfsp != NULL && (vfsp->vfs_flag & VFS_XID) == 0)		\
199 		cr = crgetmapped(cr);					\
200 	}
201 
202 /*
203  * Convert stat(2) formats to vnode types and vice versa.  (Knows about
204  * numerical order of S_IFMT and vnode types.)
205  */
206 enum vtype iftovt_tab[] = {
207 	VNON, VFIFO, VCHR, VNON, VDIR, VNON, VBLK, VNON,
208 	VREG, VNON, VLNK, VNON, VSOCK, VNON, VNON, VNON
209 };
210 
211 ushort_t vttoif_tab[] = {
212 	0, S_IFREG, S_IFDIR, S_IFBLK, S_IFCHR, S_IFLNK, S_IFIFO,
213 	S_IFDOOR, 0, S_IFSOCK, S_IFPORT, 0
214 };
215 
216 /*
217  * The system vnode cache.
218  */
219 
220 kmem_cache_t *vn_cache;
221 
222 
223 /*
224  * Vnode operations vector.
225  */
226 
227 static const fs_operation_trans_def_t vn_ops_table[] = {
228 	VOPNAME_OPEN, offsetof(struct vnodeops, vop_open),
229 	    fs_nosys, fs_nosys,
230 
231 	VOPNAME_CLOSE, offsetof(struct vnodeops, vop_close),
232 	    fs_nosys, fs_nosys,
233 
234 	VOPNAME_READ, offsetof(struct vnodeops, vop_read),
235 	    fs_nosys, fs_nosys,
236 
237 	VOPNAME_WRITE, offsetof(struct vnodeops, vop_write),
238 	    fs_nosys, fs_nosys,
239 
240 	VOPNAME_IOCTL, offsetof(struct vnodeops, vop_ioctl),
241 	    fs_nosys, fs_nosys,
242 
243 	VOPNAME_SETFL, offsetof(struct vnodeops, vop_setfl),
244 	    fs_setfl, fs_nosys,
245 
246 	VOPNAME_GETATTR, offsetof(struct vnodeops, vop_getattr),
247 	    fs_nosys, fs_nosys,
248 
249 	VOPNAME_SETATTR, offsetof(struct vnodeops, vop_setattr),
250 	    fs_nosys, fs_nosys,
251 
252 	VOPNAME_ACCESS, offsetof(struct vnodeops, vop_access),
253 	    fs_nosys, fs_nosys,
254 
255 	VOPNAME_LOOKUP, offsetof(struct vnodeops, vop_lookup),
256 	    fs_nosys, fs_nosys,
257 
258 	VOPNAME_CREATE, offsetof(struct vnodeops, vop_create),
259 	    fs_nosys, fs_nosys,
260 
261 	VOPNAME_REMOVE, offsetof(struct vnodeops, vop_remove),
262 	    fs_nosys, fs_nosys,
263 
264 	VOPNAME_LINK, offsetof(struct vnodeops, vop_link),
265 	    fs_nosys, fs_nosys,
266 
267 	VOPNAME_RENAME, offsetof(struct vnodeops, vop_rename),
268 	    fs_nosys, fs_nosys,
269 
270 	VOPNAME_MKDIR, offsetof(struct vnodeops, vop_mkdir),
271 	    fs_nosys, fs_nosys,
272 
273 	VOPNAME_RMDIR, offsetof(struct vnodeops, vop_rmdir),
274 	    fs_nosys, fs_nosys,
275 
276 	VOPNAME_READDIR, offsetof(struct vnodeops, vop_readdir),
277 	    fs_nosys, fs_nosys,
278 
279 	VOPNAME_SYMLINK, offsetof(struct vnodeops, vop_symlink),
280 	    fs_nosys, fs_nosys,
281 
282 	VOPNAME_READLINK, offsetof(struct vnodeops, vop_readlink),
283 	    fs_nosys, fs_nosys,
284 
285 	VOPNAME_FSYNC, offsetof(struct vnodeops, vop_fsync),
286 	    fs_nosys, fs_nosys,
287 
288 	VOPNAME_INACTIVE, offsetof(struct vnodeops, vop_inactive),
289 	    fs_nosys, fs_nosys,
290 
291 	VOPNAME_FID, offsetof(struct vnodeops, vop_fid),
292 	    fs_nosys, fs_nosys,
293 
294 	VOPNAME_RWLOCK, offsetof(struct vnodeops, vop_rwlock),
295 	    fs_rwlock, fs_rwlock,
296 
297 	VOPNAME_RWUNLOCK, offsetof(struct vnodeops, vop_rwunlock),
298 	    (fs_generic_func_p) fs_rwunlock,
299 	    (fs_generic_func_p) fs_rwunlock,	/* no errors allowed */
300 
301 	VOPNAME_SEEK, offsetof(struct vnodeops, vop_seek),
302 	    fs_nosys, fs_nosys,
303 
304 	VOPNAME_CMP, offsetof(struct vnodeops, vop_cmp),
305 	    fs_cmp, fs_cmp,		/* no errors allowed */
306 
307 	VOPNAME_FRLOCK, offsetof(struct vnodeops, vop_frlock),
308 	    fs_frlock, fs_nosys,
309 
310 	VOPNAME_SPACE, offsetof(struct vnodeops, vop_space),
311 	    fs_nosys, fs_nosys,
312 
313 	VOPNAME_REALVP, offsetof(struct vnodeops, vop_realvp),
314 	    fs_nosys, fs_nosys,
315 
316 	VOPNAME_GETPAGE, offsetof(struct vnodeops, vop_getpage),
317 	    fs_nosys, fs_nosys,
318 
319 	VOPNAME_PUTPAGE, offsetof(struct vnodeops, vop_putpage),
320 	    fs_nosys, fs_nosys,
321 
322 	VOPNAME_MAP, offsetof(struct vnodeops, vop_map),
323 	    (fs_generic_func_p) fs_nosys_map,
324 	    (fs_generic_func_p) fs_nosys_map,
325 
326 	VOPNAME_ADDMAP, offsetof(struct vnodeops, vop_addmap),
327 	    (fs_generic_func_p) fs_nosys_addmap,
328 	    (fs_generic_func_p) fs_nosys_addmap,
329 
330 	VOPNAME_DELMAP, offsetof(struct vnodeops, vop_delmap),
331 	    fs_nosys, fs_nosys,
332 
333 	VOPNAME_POLL, offsetof(struct vnodeops, vop_poll),
334 	    (fs_generic_func_p) fs_poll, (fs_generic_func_p) fs_nosys_poll,
335 
336 	VOPNAME_DUMP, offsetof(struct vnodeops, vop_dump),
337 	    fs_nosys, fs_nosys,
338 
339 	VOPNAME_PATHCONF, offsetof(struct vnodeops, vop_pathconf),
340 	    fs_pathconf, fs_nosys,
341 
342 	VOPNAME_PAGEIO, offsetof(struct vnodeops, vop_pageio),
343 	    fs_nosys, fs_nosys,
344 
345 	VOPNAME_DUMPCTL, offsetof(struct vnodeops, vop_dumpctl),
346 	    fs_nosys, fs_nosys,
347 
348 	VOPNAME_DISPOSE, offsetof(struct vnodeops, vop_dispose),
349 	    (fs_generic_func_p) fs_dispose,
350 	    (fs_generic_func_p) fs_nodispose,
351 
352 	VOPNAME_SETSECATTR, offsetof(struct vnodeops, vop_setsecattr),
353 	    fs_nosys, fs_nosys,
354 
355 	VOPNAME_GETSECATTR, offsetof(struct vnodeops, vop_getsecattr),
356 	    fs_fab_acl, fs_nosys,
357 
358 	VOPNAME_SHRLOCK, offsetof(struct vnodeops, vop_shrlock),
359 	    fs_shrlock, fs_nosys,
360 
361 	VOPNAME_VNEVENT, offsetof(struct vnodeops, vop_vnevent),
362 	    (fs_generic_func_p) fs_vnevent_nosupport,
363 	    (fs_generic_func_p) fs_vnevent_nosupport,
364 
365 	VOPNAME_REQZCBUF, offsetof(struct vnodeops, vop_reqzcbuf),
366 	    fs_nosys, fs_nosys,
367 
368 	VOPNAME_RETZCBUF, offsetof(struct vnodeops, vop_retzcbuf),
369 	    fs_nosys, fs_nosys,
370 
371 	NULL, 0, NULL, NULL
372 };
373 
374 /* Extensible attribute (xva) routines. */
375 
376 /*
377  * Zero out the structure, set the size of the requested/returned bitmaps,
378  * set AT_XVATTR in the embedded vattr_t's va_mask, and set up the pointer
379  * to the returned attributes array.
380  */
381 void
382 xva_init(xvattr_t *xvap)
383 {
384 	bzero(xvap, sizeof (xvattr_t));
385 	xvap->xva_mapsize = XVA_MAPSIZE;
386 	xvap->xva_magic = XVA_MAGIC;
387 	xvap->xva_vattr.va_mask = AT_XVATTR;
388 	xvap->xva_rtnattrmapp = &(xvap->xva_rtnattrmap)[0];
389 }
390 
391 /*
392  * If AT_XVATTR is set, returns a pointer to the embedded xoptattr_t
393  * structure.  Otherwise, returns NULL.
394  */
395 xoptattr_t *
396 xva_getxoptattr(xvattr_t *xvap)
397 {
398 	xoptattr_t *xoap = NULL;
399 	if (xvap->xva_vattr.va_mask & AT_XVATTR)
400 		xoap = &xvap->xva_xoptattrs;
401 	return (xoap);
402 }
403 
404 /*
405  * Used by the AVL routines to compare two vsk_anchor_t structures in the tree.
406  * We use the f_fsid reported by VFS_STATVFS() since we use that for the
407  * kstat name.
408  */
409 static int
410 vska_compar(const void *n1, const void *n2)
411 {
412 	int ret;
413 	ulong_t p1 = ((vsk_anchor_t *)n1)->vsk_fsid;
414 	ulong_t p2 = ((vsk_anchor_t *)n2)->vsk_fsid;
415 
416 	if (p1 < p2) {
417 		ret = -1;
418 	} else if (p1 > p2) {
419 		ret = 1;
420 	} else {
421 		ret = 0;
422 	}
423 
424 	return (ret);
425 }
426 
427 /*
428  * Used to create a single template which will be bcopy()ed to a newly
429  * allocated vsanchor_combo_t structure in new_vsanchor(), below.
430  */
431 static vopstats_t *
432 create_vopstats_template()
433 {
434 	vopstats_t		*vsp;
435 
436 	vsp = kmem_alloc(sizeof (vopstats_t), KM_SLEEP);
437 	bzero(vsp, sizeof (*vsp));	/* Start fresh */
438 
439 	/* VOP_OPEN */
440 	kstat_named_init(&vsp->nopen, "nopen", KSTAT_DATA_UINT64);
441 	/* VOP_CLOSE */
442 	kstat_named_init(&vsp->nclose, "nclose", KSTAT_DATA_UINT64);
443 	/* VOP_READ I/O */
444 	kstat_named_init(&vsp->nread, "nread", KSTAT_DATA_UINT64);
445 	kstat_named_init(&vsp->read_bytes, "read_bytes", KSTAT_DATA_UINT64);
446 	/* VOP_WRITE I/O */
447 	kstat_named_init(&vsp->nwrite, "nwrite", KSTAT_DATA_UINT64);
448 	kstat_named_init(&vsp->write_bytes, "write_bytes", KSTAT_DATA_UINT64);
449 	/* VOP_IOCTL */
450 	kstat_named_init(&vsp->nioctl, "nioctl", KSTAT_DATA_UINT64);
451 	/* VOP_SETFL */
452 	kstat_named_init(&vsp->nsetfl, "nsetfl", KSTAT_DATA_UINT64);
453 	/* VOP_GETATTR */
454 	kstat_named_init(&vsp->ngetattr, "ngetattr", KSTAT_DATA_UINT64);
455 	/* VOP_SETATTR */
456 	kstat_named_init(&vsp->nsetattr, "nsetattr", KSTAT_DATA_UINT64);
457 	/* VOP_ACCESS */
458 	kstat_named_init(&vsp->naccess, "naccess", KSTAT_DATA_UINT64);
459 	/* VOP_LOOKUP */
460 	kstat_named_init(&vsp->nlookup, "nlookup", KSTAT_DATA_UINT64);
461 	/* VOP_CREATE */
462 	kstat_named_init(&vsp->ncreate, "ncreate", KSTAT_DATA_UINT64);
463 	/* VOP_REMOVE */
464 	kstat_named_init(&vsp->nremove, "nremove", KSTAT_DATA_UINT64);
465 	/* VOP_LINK */
466 	kstat_named_init(&vsp->nlink, "nlink", KSTAT_DATA_UINT64);
467 	/* VOP_RENAME */
468 	kstat_named_init(&vsp->nrename, "nrename", KSTAT_DATA_UINT64);
469 	/* VOP_MKDIR */
470 	kstat_named_init(&vsp->nmkdir, "nmkdir", KSTAT_DATA_UINT64);
471 	/* VOP_RMDIR */
472 	kstat_named_init(&vsp->nrmdir, "nrmdir", KSTAT_DATA_UINT64);
473 	/* VOP_READDIR I/O */
474 	kstat_named_init(&vsp->nreaddir, "nreaddir", KSTAT_DATA_UINT64);
475 	kstat_named_init(&vsp->readdir_bytes, "readdir_bytes",
476 	    KSTAT_DATA_UINT64);
477 	/* VOP_SYMLINK */
478 	kstat_named_init(&vsp->nsymlink, "nsymlink", KSTAT_DATA_UINT64);
479 	/* VOP_READLINK */
480 	kstat_named_init(&vsp->nreadlink, "nreadlink", KSTAT_DATA_UINT64);
481 	/* VOP_FSYNC */
482 	kstat_named_init(&vsp->nfsync, "nfsync", KSTAT_DATA_UINT64);
483 	/* VOP_INACTIVE */
484 	kstat_named_init(&vsp->ninactive, "ninactive", KSTAT_DATA_UINT64);
485 	/* VOP_FID */
486 	kstat_named_init(&vsp->nfid, "nfid", KSTAT_DATA_UINT64);
487 	/* VOP_RWLOCK */
488 	kstat_named_init(&vsp->nrwlock, "nrwlock", KSTAT_DATA_UINT64);
489 	/* VOP_RWUNLOCK */
490 	kstat_named_init(&vsp->nrwunlock, "nrwunlock", KSTAT_DATA_UINT64);
491 	/* VOP_SEEK */
492 	kstat_named_init(&vsp->nseek, "nseek", KSTAT_DATA_UINT64);
493 	/* VOP_CMP */
494 	kstat_named_init(&vsp->ncmp, "ncmp", KSTAT_DATA_UINT64);
495 	/* VOP_FRLOCK */
496 	kstat_named_init(&vsp->nfrlock, "nfrlock", KSTAT_DATA_UINT64);
497 	/* VOP_SPACE */
498 	kstat_named_init(&vsp->nspace, "nspace", KSTAT_DATA_UINT64);
499 	/* VOP_REALVP */
500 	kstat_named_init(&vsp->nrealvp, "nrealvp", KSTAT_DATA_UINT64);
501 	/* VOP_GETPAGE */
502 	kstat_named_init(&vsp->ngetpage, "ngetpage", KSTAT_DATA_UINT64);
503 	/* VOP_PUTPAGE */
504 	kstat_named_init(&vsp->nputpage, "nputpage", KSTAT_DATA_UINT64);
505 	/* VOP_MAP */
506 	kstat_named_init(&vsp->nmap, "nmap", KSTAT_DATA_UINT64);
507 	/* VOP_ADDMAP */
508 	kstat_named_init(&vsp->naddmap, "naddmap", KSTAT_DATA_UINT64);
509 	/* VOP_DELMAP */
510 	kstat_named_init(&vsp->ndelmap, "ndelmap", KSTAT_DATA_UINT64);
511 	/* VOP_POLL */
512 	kstat_named_init(&vsp->npoll, "npoll", KSTAT_DATA_UINT64);
513 	/* VOP_DUMP */
514 	kstat_named_init(&vsp->ndump, "ndump", KSTAT_DATA_UINT64);
515 	/* VOP_PATHCONF */
516 	kstat_named_init(&vsp->npathconf, "npathconf", KSTAT_DATA_UINT64);
517 	/* VOP_PAGEIO */
518 	kstat_named_init(&vsp->npageio, "npageio", KSTAT_DATA_UINT64);
519 	/* VOP_DUMPCTL */
520 	kstat_named_init(&vsp->ndumpctl, "ndumpctl", KSTAT_DATA_UINT64);
521 	/* VOP_DISPOSE */
522 	kstat_named_init(&vsp->ndispose, "ndispose", KSTAT_DATA_UINT64);
523 	/* VOP_SETSECATTR */
524 	kstat_named_init(&vsp->nsetsecattr, "nsetsecattr", KSTAT_DATA_UINT64);
525 	/* VOP_GETSECATTR */
526 	kstat_named_init(&vsp->ngetsecattr, "ngetsecattr", KSTAT_DATA_UINT64);
527 	/* VOP_SHRLOCK */
528 	kstat_named_init(&vsp->nshrlock, "nshrlock", KSTAT_DATA_UINT64);
529 	/* VOP_VNEVENT */
530 	kstat_named_init(&vsp->nvnevent, "nvnevent", KSTAT_DATA_UINT64);
531 	/* VOP_REQZCBUF */
532 	kstat_named_init(&vsp->nreqzcbuf, "nreqzcbuf", KSTAT_DATA_UINT64);
533 	/* VOP_RETZCBUF */
534 	kstat_named_init(&vsp->nretzcbuf, "nretzcbuf", KSTAT_DATA_UINT64);
535 
536 	return (vsp);
537 }
538 
539 /*
540  * Creates a kstat structure associated with a vopstats structure.
541  */
542 kstat_t *
543 new_vskstat(char *ksname, vopstats_t *vsp)
544 {
545 	kstat_t		*ksp;
546 
547 	if (!vopstats_enabled) {
548 		return (NULL);
549 	}
550 
551 	ksp = kstat_create("unix", 0, ksname, "misc", KSTAT_TYPE_NAMED,
552 	    sizeof (vopstats_t)/sizeof (kstat_named_t),
553 	    KSTAT_FLAG_VIRTUAL|KSTAT_FLAG_WRITABLE);
554 	if (ksp) {
555 		ksp->ks_data = vsp;
556 		kstat_install(ksp);
557 	}
558 
559 	return (ksp);
560 }
561 
562 /*
563  * Called from vfsinit() to initialize the support mechanisms for vopstats
564  */
565 void
566 vopstats_startup()
567 {
568 	if (!vopstats_enabled)
569 		return;
570 
571 	/*
572 	 * Creates the AVL tree which holds per-vfs vopstat anchors.  This
573 	 * is necessary since we need to check if a kstat exists before we
574 	 * attempt to create it.  Also, initialize its lock.
575 	 */
576 	avl_create(&vskstat_tree, vska_compar, sizeof (vsk_anchor_t),
577 	    offsetof(vsk_anchor_t, vsk_node));
578 	mutex_init(&vskstat_tree_lock, NULL, MUTEX_DEFAULT, NULL);
579 
580 	vsk_anchor_cache = kmem_cache_create("vsk_anchor_cache",
581 	    sizeof (vsk_anchor_t), sizeof (uintptr_t), NULL, NULL, NULL,
582 	    NULL, NULL, 0);
583 
584 	/*
585 	 * Set up the array of pointers for the vopstats-by-FS-type.
586 	 * The entries will be allocated/initialized as each file system
587 	 * goes through modload/mod_installfs.
588 	 */
589 	vopstats_fstype = (vopstats_t **)kmem_zalloc(
590 	    (sizeof (vopstats_t *) * nfstype), KM_SLEEP);
591 
592 	/* Set up the global vopstats initialization template */
593 	vs_templatep = create_vopstats_template();
594 }
595 
596 /*
597  * We need to have the all of the counters zeroed.
598  * The initialization of the vopstats_t includes on the order of
599  * 50 calls to kstat_named_init().  Rather that do that on every call,
600  * we do it once in a template (vs_templatep) then bcopy it over.
601  */
602 void
603 initialize_vopstats(vopstats_t *vsp)
604 {
605 	if (vsp == NULL)
606 		return;
607 
608 	bcopy(vs_templatep, vsp, sizeof (vopstats_t));
609 }
610 
611 /*
612  * If possible, determine which vopstats by fstype to use and
613  * return a pointer to the caller.
614  */
615 vopstats_t *
616 get_fstype_vopstats(vfs_t *vfsp, struct vfssw *vswp)
617 {
618 	int		fstype = 0;	/* Index into vfssw[] */
619 	vopstats_t	*vsp = NULL;
620 
621 	if (vfsp == NULL || (vfsp->vfs_flag & VFS_STATS) == 0 ||
622 	    !vopstats_enabled)
623 		return (NULL);
624 	/*
625 	 * Set up the fstype.  We go to so much trouble because all versions
626 	 * of NFS use the same fstype in their vfs even though they have
627 	 * distinct entries in the vfssw[] table.
628 	 * NOTE: A special vfs (e.g., EIO_vfs) may not have an entry.
629 	 */
630 	if (vswp) {
631 		fstype = vswp - vfssw;	/* Gets us the index */
632 	} else {
633 		fstype = vfsp->vfs_fstype;
634 	}
635 
636 	/*
637 	 * Point to the per-fstype vopstats. The only valid values are
638 	 * non-zero positive values less than the number of vfssw[] table
639 	 * entries.
640 	 */
641 	if (fstype > 0 && fstype < nfstype) {
642 		vsp = vopstats_fstype[fstype];
643 	}
644 
645 	return (vsp);
646 }
647 
648 /*
649  * Generate a kstat name, create the kstat structure, and allocate a
650  * vsk_anchor_t to hold it together.  Return the pointer to the vsk_anchor_t
651  * to the caller.  This must only be called from a mount.
652  */
653 vsk_anchor_t *
654 get_vskstat_anchor(vfs_t *vfsp)
655 {
656 	char		kstatstr[KSTAT_STRLEN]; /* kstat name for vopstats */
657 	statvfs64_t	statvfsbuf;		/* Needed to find f_fsid */
658 	vsk_anchor_t	*vskp = NULL;		/* vfs <--> kstat anchor */
659 	kstat_t		*ksp;			/* Ptr to new kstat */
660 	avl_index_t	where;			/* Location in the AVL tree */
661 
662 	if (vfsp == NULL || vfsp->vfs_implp == NULL ||
663 	    (vfsp->vfs_flag & VFS_STATS) == 0 || !vopstats_enabled)
664 		return (NULL);
665 
666 	/* Need to get the fsid to build a kstat name */
667 	if (VFS_STATVFS(vfsp, &statvfsbuf) == 0) {
668 		/* Create a name for our kstats based on fsid */
669 		(void) snprintf(kstatstr, KSTAT_STRLEN, "%s%lx",
670 		    VOPSTATS_STR, statvfsbuf.f_fsid);
671 
672 		/* Allocate and initialize the vsk_anchor_t */
673 		vskp = kmem_cache_alloc(vsk_anchor_cache, KM_SLEEP);
674 		bzero(vskp, sizeof (*vskp));
675 		vskp->vsk_fsid = statvfsbuf.f_fsid;
676 
677 		mutex_enter(&vskstat_tree_lock);
678 		if (avl_find(&vskstat_tree, vskp, &where) == NULL) {
679 			avl_insert(&vskstat_tree, vskp, where);
680 			mutex_exit(&vskstat_tree_lock);
681 
682 			/*
683 			 * Now that we've got the anchor in the AVL
684 			 * tree, we can create the kstat.
685 			 */
686 			ksp = new_vskstat(kstatstr, &vfsp->vfs_vopstats);
687 			if (ksp) {
688 				vskp->vsk_ksp = ksp;
689 			}
690 		} else {
691 			/* Oops, found one! Release memory and lock. */
692 			mutex_exit(&vskstat_tree_lock);
693 			kmem_cache_free(vsk_anchor_cache, vskp);
694 			vskp = NULL;
695 		}
696 	}
697 	return (vskp);
698 }
699 
700 /*
701  * We're in the process of tearing down the vfs and need to cleanup
702  * the data structures associated with the vopstats. Must only be called
703  * from dounmount().
704  */
705 void
706 teardown_vopstats(vfs_t *vfsp)
707 {
708 	vsk_anchor_t	*vskap;
709 	avl_index_t	where;
710 
711 	if (vfsp == NULL || vfsp->vfs_implp == NULL ||
712 	    (vfsp->vfs_flag & VFS_STATS) == 0 || !vopstats_enabled)
713 		return;
714 
715 	/* This is a safe check since VFS_STATS must be set (see above) */
716 	if ((vskap = vfsp->vfs_vskap) == NULL)
717 		return;
718 
719 	/* Whack the pointer right away */
720 	vfsp->vfs_vskap = NULL;
721 
722 	/* Lock the tree, remove the node, and delete the kstat */
723 	mutex_enter(&vskstat_tree_lock);
724 	if (avl_find(&vskstat_tree, vskap, &where)) {
725 		avl_remove(&vskstat_tree, vskap);
726 	}
727 
728 	if (vskap->vsk_ksp) {
729 		kstat_delete(vskap->vsk_ksp);
730 	}
731 	mutex_exit(&vskstat_tree_lock);
732 
733 	kmem_cache_free(vsk_anchor_cache, vskap);
734 }
735 
736 /*
737  * Read or write a vnode.  Called from kernel code.
738  */
739 int
740 vn_rdwr(
741 	enum uio_rw rw,
742 	struct vnode *vp,
743 	caddr_t base,
744 	ssize_t len,
745 	offset_t offset,
746 	enum uio_seg seg,
747 	int ioflag,
748 	rlim64_t ulimit,	/* meaningful only if rw is UIO_WRITE */
749 	cred_t *cr,
750 	ssize_t *residp)
751 {
752 	struct uio uio;
753 	struct iovec iov;
754 	int error;
755 	int in_crit = 0;
756 
757 	if (rw == UIO_WRITE && ISROFILE(vp))
758 		return (EROFS);
759 
760 	if (len < 0)
761 		return (EIO);
762 
763 	VOPXID_MAP_CR(vp, cr);
764 
765 	iov.iov_base = base;
766 	iov.iov_len = len;
767 	uio.uio_iov = &iov;
768 	uio.uio_iovcnt = 1;
769 	uio.uio_loffset = offset;
770 	uio.uio_segflg = (short)seg;
771 	uio.uio_resid = len;
772 	uio.uio_llimit = ulimit;
773 
774 	/*
775 	 * We have to enter the critical region before calling VOP_RWLOCK
776 	 * to avoid a deadlock with ufs.
777 	 */
778 	if (nbl_need_check(vp)) {
779 		int svmand;
780 
781 		nbl_start_crit(vp, RW_READER);
782 		in_crit = 1;
783 		error = nbl_svmand(vp, cr, &svmand);
784 		if (error != 0)
785 			goto done;
786 		if (nbl_conflict(vp, rw == UIO_WRITE ? NBL_WRITE : NBL_READ,
787 		    uio.uio_offset, uio.uio_resid, svmand, NULL)) {
788 			error = EACCES;
789 			goto done;
790 		}
791 	}
792 
793 	(void) VOP_RWLOCK(vp,
794 	    rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE, NULL);
795 	if (rw == UIO_WRITE) {
796 		uio.uio_fmode = FWRITE;
797 		uio.uio_extflg = UIO_COPY_DEFAULT;
798 		error = VOP_WRITE(vp, &uio, ioflag, cr, NULL);
799 	} else {
800 		uio.uio_fmode = FREAD;
801 		uio.uio_extflg = UIO_COPY_CACHED;
802 		error = VOP_READ(vp, &uio, ioflag, cr, NULL);
803 	}
804 	VOP_RWUNLOCK(vp,
805 	    rw == UIO_WRITE ? V_WRITELOCK_TRUE : V_WRITELOCK_FALSE, NULL);
806 	if (residp)
807 		*residp = uio.uio_resid;
808 	else if (uio.uio_resid)
809 		error = EIO;
810 
811 done:
812 	if (in_crit)
813 		nbl_end_crit(vp);
814 	return (error);
815 }
816 
817 /*
818  * Release a vnode.  Call VOP_INACTIVE on last reference or
819  * decrement reference count.
820  *
821  * To avoid race conditions, the v_count is left at 1 for
822  * the call to VOP_INACTIVE. This prevents another thread
823  * from reclaiming and releasing the vnode *before* the
824  * VOP_INACTIVE routine has a chance to destroy the vnode.
825  * We can't have more than 1 thread calling VOP_INACTIVE
826  * on a vnode.
827  */
828 void
829 vn_rele(vnode_t *vp)
830 {
831 	VERIFY(vp->v_count > 0);
832 	mutex_enter(&vp->v_lock);
833 	if (vp->v_count == 1) {
834 		mutex_exit(&vp->v_lock);
835 		VOP_INACTIVE(vp, CRED(), NULL);
836 		return;
837 	}
838 	vp->v_count--;
839 	mutex_exit(&vp->v_lock);
840 }
841 
842 /*
843  * Release a vnode referenced by the DNLC. Multiple DNLC references are treated
844  * as a single reference, so v_count is not decremented until the last DNLC hold
845  * is released. This makes it possible to distinguish vnodes that are referenced
846  * only by the DNLC.
847  */
848 void
849 vn_rele_dnlc(vnode_t *vp)
850 {
851 	VERIFY((vp->v_count > 0) && (vp->v_count_dnlc > 0));
852 	mutex_enter(&vp->v_lock);
853 	if (--vp->v_count_dnlc == 0) {
854 		if (vp->v_count == 1) {
855 			mutex_exit(&vp->v_lock);
856 			VOP_INACTIVE(vp, CRED(), NULL);
857 			return;
858 		}
859 		vp->v_count--;
860 	}
861 	mutex_exit(&vp->v_lock);
862 }
863 
864 /*
865  * Like vn_rele() except that it clears v_stream under v_lock.
866  * This is used by sockfs when it dismantels the association between
867  * the sockfs node and the vnode in the underlaying file system.
868  * v_lock has to be held to prevent a thread coming through the lookupname
869  * path from accessing a stream head that is going away.
870  */
871 void
872 vn_rele_stream(vnode_t *vp)
873 {
874 	VERIFY(vp->v_count > 0);
875 	mutex_enter(&vp->v_lock);
876 	vp->v_stream = NULL;
877 	if (vp->v_count == 1) {
878 		mutex_exit(&vp->v_lock);
879 		VOP_INACTIVE(vp, CRED(), NULL);
880 		return;
881 	}
882 	vp->v_count--;
883 	mutex_exit(&vp->v_lock);
884 }
885 
886 static void
887 vn_rele_inactive(vnode_t *vp)
888 {
889 	VOP_INACTIVE(vp, CRED(), NULL);
890 }
891 
892 /*
893  * Like vn_rele() except if we are going to call VOP_INACTIVE() then do it
894  * asynchronously using a taskq. This can avoid deadlocks caused by re-entering
895  * the file system as a result of releasing the vnode. Note, file systems
896  * already have to handle the race where the vnode is incremented before the
897  * inactive routine is called and does its locking.
898  *
899  * Warning: Excessive use of this routine can lead to performance problems.
900  * This is because taskqs throttle back allocation if too many are created.
901  */
902 void
903 vn_rele_async(vnode_t *vp, taskq_t *taskq)
904 {
905 	VERIFY(vp->v_count > 0);
906 	mutex_enter(&vp->v_lock);
907 	if (vp->v_count == 1) {
908 		mutex_exit(&vp->v_lock);
909 		VERIFY(taskq_dispatch(taskq, (task_func_t *)vn_rele_inactive,
910 		    vp, TQ_SLEEP) != NULL);
911 		return;
912 	}
913 	vp->v_count--;
914 	mutex_exit(&vp->v_lock);
915 }
916 
917 int
918 vn_open(
919 	char *pnamep,
920 	enum uio_seg seg,
921 	int filemode,
922 	int createmode,
923 	struct vnode **vpp,
924 	enum create crwhy,
925 	mode_t umask)
926 {
927 	return (vn_openat(pnamep, seg, filemode, createmode, vpp, crwhy,
928 	    umask, NULL, -1));
929 }
930 
931 
932 /*
933  * Open/create a vnode.
934  * This may be callable by the kernel, the only known use
935  * of user context being that the current user credentials
936  * are used for permissions.  crwhy is defined iff filemode & FCREAT.
937  */
938 int
939 vn_openat(
940 	char *pnamep,
941 	enum uio_seg seg,
942 	int filemode,
943 	int createmode,
944 	struct vnode **vpp,
945 	enum create crwhy,
946 	mode_t umask,
947 	struct vnode *startvp,
948 	int fd)
949 {
950 	struct vnode *vp;
951 	int mode;
952 	int accessflags;
953 	int error;
954 	int in_crit = 0;
955 	int open_done = 0;
956 	int shrlock_done = 0;
957 	struct vattr vattr;
958 	enum symfollow follow;
959 	int estale_retry = 0;
960 	struct shrlock shr;
961 	struct shr_locowner shr_own;
962 
963 	mode = 0;
964 	accessflags = 0;
965 	if (filemode & FREAD)
966 		mode |= VREAD;
967 	if (filemode & (FWRITE|FTRUNC))
968 		mode |= VWRITE;
969 	if (filemode & (FSEARCH|FEXEC|FXATTRDIROPEN))
970 		mode |= VEXEC;
971 
972 	/* symlink interpretation */
973 	if (filemode & FNOFOLLOW)
974 		follow = NO_FOLLOW;
975 	else
976 		follow = FOLLOW;
977 
978 	if (filemode & FAPPEND)
979 		accessflags |= V_APPEND;
980 
981 top:
982 	if (filemode & FCREAT) {
983 		enum vcexcl excl;
984 
985 		/*
986 		 * Wish to create a file.
987 		 */
988 		vattr.va_type = VREG;
989 		vattr.va_mode = createmode;
990 		vattr.va_mask = AT_TYPE|AT_MODE;
991 		if (filemode & FTRUNC) {
992 			vattr.va_size = 0;
993 			vattr.va_mask |= AT_SIZE;
994 		}
995 		if (filemode & FEXCL)
996 			excl = EXCL;
997 		else
998 			excl = NONEXCL;
999 
1000 		if (error =
1001 		    vn_createat(pnamep, seg, &vattr, excl, mode, &vp, crwhy,
1002 		    (filemode & ~(FTRUNC|FEXCL)), umask, startvp))
1003 			return (error);
1004 	} else {
1005 		/*
1006 		 * Wish to open a file.  Just look it up.
1007 		 */
1008 		if (error = lookupnameat(pnamep, seg, follow,
1009 		    NULLVPP, &vp, startvp)) {
1010 			if ((error == ESTALE) &&
1011 			    fs_need_estale_retry(estale_retry++))
1012 				goto top;
1013 			return (error);
1014 		}
1015 
1016 		/*
1017 		 * Get the attributes to check whether file is large.
1018 		 * We do this only if the FOFFMAX flag is not set and
1019 		 * only for regular files.
1020 		 */
1021 
1022 		if (!(filemode & FOFFMAX) && (vp->v_type == VREG)) {
1023 			vattr.va_mask = AT_SIZE;
1024 			if ((error = VOP_GETATTR(vp, &vattr, 0,
1025 			    CRED(), NULL))) {
1026 				goto out;
1027 			}
1028 			if (vattr.va_size > (u_offset_t)MAXOFF32_T) {
1029 				/*
1030 				 * Large File API - regular open fails
1031 				 * if FOFFMAX flag is set in file mode
1032 				 */
1033 				error = EOVERFLOW;
1034 				goto out;
1035 			}
1036 		}
1037 		/*
1038 		 * Can't write directories, active texts, or
1039 		 * read-only filesystems.  Can't truncate files
1040 		 * on which mandatory locking is in effect.
1041 		 */
1042 		if (filemode & (FWRITE|FTRUNC)) {
1043 			/*
1044 			 * Allow writable directory if VDIROPEN flag is set.
1045 			 */
1046 			if (vp->v_type == VDIR && !(vp->v_flag & VDIROPEN)) {
1047 				error = EISDIR;
1048 				goto out;
1049 			}
1050 			if (ISROFILE(vp)) {
1051 				error = EROFS;
1052 				goto out;
1053 			}
1054 			/*
1055 			 * Can't truncate files on which
1056 			 * sysv mandatory locking is in effect.
1057 			 */
1058 			if (filemode & FTRUNC) {
1059 				vnode_t *rvp;
1060 
1061 				if (VOP_REALVP(vp, &rvp, NULL) != 0)
1062 					rvp = vp;
1063 				if (rvp->v_filocks != NULL) {
1064 					vattr.va_mask = AT_MODE;
1065 					if ((error = VOP_GETATTR(vp,
1066 					    &vattr, 0, CRED(), NULL)) == 0 &&
1067 					    MANDLOCK(vp, vattr.va_mode))
1068 						error = EAGAIN;
1069 				}
1070 			}
1071 			if (error)
1072 				goto out;
1073 		}
1074 		/*
1075 		 * Check permissions.
1076 		 */
1077 		if (error = VOP_ACCESS(vp, mode, accessflags, CRED(), NULL))
1078 			goto out;
1079 		/*
1080 		 * Require FSEARCH to return a directory.
1081 		 * Require FEXEC to return a regular file.
1082 		 */
1083 		if ((filemode & FSEARCH) && vp->v_type != VDIR) {
1084 			error = ENOTDIR;
1085 			goto out;
1086 		}
1087 		if ((filemode & FEXEC) && vp->v_type != VREG) {
1088 			error = ENOEXEC;	/* XXX: error code? */
1089 			goto out;
1090 		}
1091 	}
1092 
1093 	/*
1094 	 * Do remaining checks for FNOFOLLOW and FNOLINKS.
1095 	 */
1096 	if ((filemode & FNOFOLLOW) && vp->v_type == VLNK) {
1097 		error = ELOOP;
1098 		goto out;
1099 	}
1100 	if (filemode & FNOLINKS) {
1101 		vattr.va_mask = AT_NLINK;
1102 		if ((error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL))) {
1103 			goto out;
1104 		}
1105 		if (vattr.va_nlink != 1) {
1106 			error = EMLINK;
1107 			goto out;
1108 		}
1109 	}
1110 
1111 	/*
1112 	 * Opening a socket corresponding to the AF_UNIX pathname
1113 	 * in the filesystem name space is not supported.
1114 	 * However, VSOCK nodes in namefs are supported in order
1115 	 * to make fattach work for sockets.
1116 	 *
1117 	 * XXX This uses VOP_REALVP to distinguish between
1118 	 * an unopened namefs node (where VOP_REALVP returns a
1119 	 * different VSOCK vnode) and a VSOCK created by vn_create
1120 	 * in some file system (where VOP_REALVP would never return
1121 	 * a different vnode).
1122 	 */
1123 	if (vp->v_type == VSOCK) {
1124 		struct vnode *nvp;
1125 
1126 		error = VOP_REALVP(vp, &nvp, NULL);
1127 		if (error != 0 || nvp == NULL || nvp == vp ||
1128 		    nvp->v_type != VSOCK) {
1129 			error = EOPNOTSUPP;
1130 			goto out;
1131 		}
1132 	}
1133 
1134 	if ((vp->v_type == VREG) && nbl_need_check(vp)) {
1135 		/* get share reservation */
1136 		shr.s_access = 0;
1137 		if (filemode & FWRITE)
1138 			shr.s_access |= F_WRACC;
1139 		if (filemode & FREAD)
1140 			shr.s_access |= F_RDACC;
1141 		shr.s_deny = 0;
1142 		shr.s_sysid = 0;
1143 		shr.s_pid = ttoproc(curthread)->p_pid;
1144 		shr_own.sl_pid = shr.s_pid;
1145 		shr_own.sl_id = fd;
1146 		shr.s_own_len = sizeof (shr_own);
1147 		shr.s_owner = (caddr_t)&shr_own;
1148 		error = VOP_SHRLOCK(vp, F_SHARE_NBMAND, &shr, filemode, CRED(),
1149 		    NULL);
1150 		if (error)
1151 			goto out;
1152 		shrlock_done = 1;
1153 
1154 		/* nbmand conflict check if truncating file */
1155 		if ((filemode & FTRUNC) && !(filemode & FCREAT)) {
1156 			nbl_start_crit(vp, RW_READER);
1157 			in_crit = 1;
1158 
1159 			vattr.va_mask = AT_SIZE;
1160 			if (error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL))
1161 				goto out;
1162 			if (nbl_conflict(vp, NBL_WRITE, 0, vattr.va_size, 0,
1163 			    NULL)) {
1164 				error = EACCES;
1165 				goto out;
1166 			}
1167 		}
1168 	}
1169 
1170 	/*
1171 	 * Do opening protocol.
1172 	 */
1173 	error = VOP_OPEN(&vp, filemode, CRED(), NULL);
1174 	if (error)
1175 		goto out;
1176 	open_done = 1;
1177 
1178 	/*
1179 	 * Truncate if required.
1180 	 */
1181 	if ((filemode & FTRUNC) && !(filemode & FCREAT)) {
1182 		vattr.va_size = 0;
1183 		vattr.va_mask = AT_SIZE;
1184 		if ((error = VOP_SETATTR(vp, &vattr, 0, CRED(), NULL)) != 0)
1185 			goto out;
1186 	}
1187 out:
1188 	ASSERT(vp->v_count > 0);
1189 
1190 	if (in_crit) {
1191 		nbl_end_crit(vp);
1192 		in_crit = 0;
1193 	}
1194 	if (error) {
1195 		if (open_done) {
1196 			(void) VOP_CLOSE(vp, filemode, 1, (offset_t)0, CRED(),
1197 			    NULL);
1198 			open_done = 0;
1199 			shrlock_done = 0;
1200 		}
1201 		if (shrlock_done) {
1202 			(void) VOP_SHRLOCK(vp, F_UNSHARE, &shr, 0, CRED(),
1203 			    NULL);
1204 			shrlock_done = 0;
1205 		}
1206 
1207 		/*
1208 		 * The following clause was added to handle a problem
1209 		 * with NFS consistency.  It is possible that a lookup
1210 		 * of the file to be opened succeeded, but the file
1211 		 * itself doesn't actually exist on the server.  This
1212 		 * is chiefly due to the DNLC containing an entry for
1213 		 * the file which has been removed on the server.  In
1214 		 * this case, we just start over.  If there was some
1215 		 * other cause for the ESTALE error, then the lookup
1216 		 * of the file will fail and the error will be returned
1217 		 * above instead of looping around from here.
1218 		 */
1219 		VN_RELE(vp);
1220 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1221 			goto top;
1222 	} else
1223 		*vpp = vp;
1224 	return (error);
1225 }
1226 
1227 /*
1228  * The following two accessor functions are for the NFSv4 server.  Since there
1229  * is no VOP_OPEN_UP/DOWNGRADE we need a way for the NFS server to keep the
1230  * vnode open counts correct when a client "upgrades" an open or does an
1231  * open_downgrade.  In NFS, an upgrade or downgrade can not only change the
1232  * open mode (add or subtract read or write), but also change the share/deny
1233  * modes.  However, share reservations are not integrated with OPEN, yet, so
1234  * we need to handle each separately.  These functions are cleaner than having
1235  * the NFS server manipulate the counts directly, however, nobody else should
1236  * use these functions.
1237  */
1238 void
1239 vn_open_upgrade(
1240 	vnode_t *vp,
1241 	int filemode)
1242 {
1243 	ASSERT(vp->v_type == VREG);
1244 
1245 	if (filemode & FREAD)
1246 		atomic_add_32(&(vp->v_rdcnt), 1);
1247 	if (filemode & FWRITE)
1248 		atomic_add_32(&(vp->v_wrcnt), 1);
1249 
1250 }
1251 
1252 void
1253 vn_open_downgrade(
1254 	vnode_t *vp,
1255 	int filemode)
1256 {
1257 	ASSERT(vp->v_type == VREG);
1258 
1259 	if (filemode & FREAD) {
1260 		ASSERT(vp->v_rdcnt > 0);
1261 		atomic_add_32(&(vp->v_rdcnt), -1);
1262 	}
1263 	if (filemode & FWRITE) {
1264 		ASSERT(vp->v_wrcnt > 0);
1265 		atomic_add_32(&(vp->v_wrcnt), -1);
1266 	}
1267 
1268 }
1269 
1270 int
1271 vn_create(
1272 	char *pnamep,
1273 	enum uio_seg seg,
1274 	struct vattr *vap,
1275 	enum vcexcl excl,
1276 	int mode,
1277 	struct vnode **vpp,
1278 	enum create why,
1279 	int flag,
1280 	mode_t umask)
1281 {
1282 	return (vn_createat(pnamep, seg, vap, excl, mode, vpp, why, flag,
1283 	    umask, NULL));
1284 }
1285 
1286 /*
1287  * Create a vnode (makenode).
1288  */
1289 int
1290 vn_createat(
1291 	char *pnamep,
1292 	enum uio_seg seg,
1293 	struct vattr *vap,
1294 	enum vcexcl excl,
1295 	int mode,
1296 	struct vnode **vpp,
1297 	enum create why,
1298 	int flag,
1299 	mode_t umask,
1300 	struct vnode *startvp)
1301 {
1302 	struct vnode *dvp;	/* ptr to parent dir vnode */
1303 	struct vnode *vp = NULL;
1304 	struct pathname pn;
1305 	int error;
1306 	int in_crit = 0;
1307 	struct vattr vattr;
1308 	enum symfollow follow;
1309 	int estale_retry = 0;
1310 	uint32_t auditing = AU_AUDITING();
1311 
1312 	ASSERT((vap->va_mask & (AT_TYPE|AT_MODE)) == (AT_TYPE|AT_MODE));
1313 
1314 	/* symlink interpretation */
1315 	if ((flag & FNOFOLLOW) || excl == EXCL)
1316 		follow = NO_FOLLOW;
1317 	else
1318 		follow = FOLLOW;
1319 	flag &= ~(FNOFOLLOW|FNOLINKS);
1320 
1321 top:
1322 	/*
1323 	 * Lookup directory.
1324 	 * If new object is a file, call lower level to create it.
1325 	 * Note that it is up to the lower level to enforce exclusive
1326 	 * creation, if the file is already there.
1327 	 * This allows the lower level to do whatever
1328 	 * locking or protocol that is needed to prevent races.
1329 	 * If the new object is directory call lower level to make
1330 	 * the new directory, with "." and "..".
1331 	 */
1332 	if (error = pn_get(pnamep, seg, &pn))
1333 		return (error);
1334 	if (auditing)
1335 		audit_vncreate_start();
1336 	dvp = NULL;
1337 	*vpp = NULL;
1338 	/*
1339 	 * lookup will find the parent directory for the vnode.
1340 	 * When it is done the pn holds the name of the entry
1341 	 * in the directory.
1342 	 * If this is a non-exclusive create we also find the node itself.
1343 	 */
1344 	error = lookuppnat(&pn, NULL, follow, &dvp,
1345 	    (excl == EXCL) ? NULLVPP : vpp, startvp);
1346 	if (error) {
1347 		pn_free(&pn);
1348 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1349 			goto top;
1350 		if (why == CRMKDIR && error == EINVAL)
1351 			error = EEXIST;		/* SVID */
1352 		return (error);
1353 	}
1354 
1355 	if (why != CRMKNOD)
1356 		vap->va_mode &= ~VSVTX;
1357 
1358 	/*
1359 	 * If default ACLs are defined for the directory don't apply the
1360 	 * umask if umask is passed.
1361 	 */
1362 
1363 	if (umask) {
1364 
1365 		vsecattr_t vsec;
1366 
1367 		vsec.vsa_aclcnt = 0;
1368 		vsec.vsa_aclentp = NULL;
1369 		vsec.vsa_dfaclcnt = 0;
1370 		vsec.vsa_dfaclentp = NULL;
1371 		vsec.vsa_mask = VSA_DFACLCNT;
1372 		error = VOP_GETSECATTR(dvp, &vsec, 0, CRED(), NULL);
1373 		/*
1374 		 * If error is ENOSYS then treat it as no error
1375 		 * Don't want to force all file systems to support
1376 		 * aclent_t style of ACL's.
1377 		 */
1378 		if (error == ENOSYS)
1379 			error = 0;
1380 		if (error) {
1381 			if (*vpp != NULL)
1382 				VN_RELE(*vpp);
1383 			goto out;
1384 		} else {
1385 			/*
1386 			 * Apply the umask if no default ACLs.
1387 			 */
1388 			if (vsec.vsa_dfaclcnt == 0)
1389 				vap->va_mode &= ~umask;
1390 
1391 			/*
1392 			 * VOP_GETSECATTR() may have allocated memory for
1393 			 * ACLs we didn't request, so double-check and
1394 			 * free it if necessary.
1395 			 */
1396 			if (vsec.vsa_aclcnt && vsec.vsa_aclentp != NULL)
1397 				kmem_free((caddr_t)vsec.vsa_aclentp,
1398 				    vsec.vsa_aclcnt * sizeof (aclent_t));
1399 			if (vsec.vsa_dfaclcnt && vsec.vsa_dfaclentp != NULL)
1400 				kmem_free((caddr_t)vsec.vsa_dfaclentp,
1401 				    vsec.vsa_dfaclcnt * sizeof (aclent_t));
1402 		}
1403 	}
1404 
1405 	/*
1406 	 * In general we want to generate EROFS if the file system is
1407 	 * readonly.  However, POSIX (IEEE Std. 1003.1) section 5.3.1
1408 	 * documents the open system call, and it says that O_CREAT has no
1409 	 * effect if the file already exists.  Bug 1119649 states
1410 	 * that open(path, O_CREAT, ...) fails when attempting to open an
1411 	 * existing file on a read only file system.  Thus, the first part
1412 	 * of the following if statement has 3 checks:
1413 	 *	if the file exists &&
1414 	 *		it is being open with write access &&
1415 	 *		the file system is read only
1416 	 *	then generate EROFS
1417 	 */
1418 	if ((*vpp != NULL && (mode & VWRITE) && ISROFILE(*vpp)) ||
1419 	    (*vpp == NULL && dvp->v_vfsp->vfs_flag & VFS_RDONLY)) {
1420 		if (*vpp)
1421 			VN_RELE(*vpp);
1422 		error = EROFS;
1423 	} else if (excl == NONEXCL && *vpp != NULL) {
1424 		vnode_t *rvp;
1425 
1426 		/*
1427 		 * File already exists.  If a mandatory lock has been
1428 		 * applied, return error.
1429 		 */
1430 		vp = *vpp;
1431 		if (VOP_REALVP(vp, &rvp, NULL) != 0)
1432 			rvp = vp;
1433 		if ((vap->va_mask & AT_SIZE) && nbl_need_check(vp)) {
1434 			nbl_start_crit(vp, RW_READER);
1435 			in_crit = 1;
1436 		}
1437 		if (rvp->v_filocks != NULL || rvp->v_shrlocks != NULL) {
1438 			vattr.va_mask = AT_MODE|AT_SIZE;
1439 			if (error = VOP_GETATTR(vp, &vattr, 0, CRED(), NULL)) {
1440 				goto out;
1441 			}
1442 			if (MANDLOCK(vp, vattr.va_mode)) {
1443 				error = EAGAIN;
1444 				goto out;
1445 			}
1446 			/*
1447 			 * File cannot be truncated if non-blocking mandatory
1448 			 * locks are currently on the file.
1449 			 */
1450 			if ((vap->va_mask & AT_SIZE) && in_crit) {
1451 				u_offset_t offset;
1452 				ssize_t length;
1453 
1454 				offset = vap->va_size > vattr.va_size ?
1455 				    vattr.va_size : vap->va_size;
1456 				length = vap->va_size > vattr.va_size ?
1457 				    vap->va_size - vattr.va_size :
1458 				    vattr.va_size - vap->va_size;
1459 				if (nbl_conflict(vp, NBL_WRITE, offset,
1460 				    length, 0, NULL)) {
1461 					error = EACCES;
1462 					goto out;
1463 				}
1464 			}
1465 		}
1466 
1467 		/*
1468 		 * If the file is the root of a VFS, we've crossed a
1469 		 * mount point and the "containing" directory that we
1470 		 * acquired above (dvp) is irrelevant because it's in
1471 		 * a different file system.  We apply VOP_CREATE to the
1472 		 * target itself instead of to the containing directory
1473 		 * and supply a null path name to indicate (conventionally)
1474 		 * the node itself as the "component" of interest.
1475 		 *
1476 		 * The intercession of the file system is necessary to
1477 		 * ensure that the appropriate permission checks are
1478 		 * done.
1479 		 */
1480 		if (vp->v_flag & VROOT) {
1481 			ASSERT(why != CRMKDIR);
1482 			error = VOP_CREATE(vp, "", vap, excl, mode, vpp,
1483 			    CRED(), flag, NULL, NULL);
1484 			/*
1485 			 * If the create succeeded, it will have created
1486 			 * a new reference to the vnode.  Give up the
1487 			 * original reference.  The assertion should not
1488 			 * get triggered because NBMAND locks only apply to
1489 			 * VREG files.  And if in_crit is non-zero for some
1490 			 * reason, detect that here, rather than when we
1491 			 * deference a null vp.
1492 			 */
1493 			ASSERT(in_crit == 0);
1494 			VN_RELE(vp);
1495 			vp = NULL;
1496 			goto out;
1497 		}
1498 
1499 		/*
1500 		 * Large File API - non-large open (FOFFMAX flag not set)
1501 		 * of regular file fails if the file size exceeds MAXOFF32_T.
1502 		 */
1503 		if (why != CRMKDIR &&
1504 		    !(flag & FOFFMAX) &&
1505 		    (vp->v_type == VREG)) {
1506 			vattr.va_mask = AT_SIZE;
1507 			if ((error = VOP_GETATTR(vp, &vattr, 0,
1508 			    CRED(), NULL))) {
1509 				goto out;
1510 			}
1511 			if ((vattr.va_size > (u_offset_t)MAXOFF32_T)) {
1512 				error = EOVERFLOW;
1513 				goto out;
1514 			}
1515 		}
1516 	}
1517 
1518 	if (error == 0) {
1519 		/*
1520 		 * Call mkdir() if specified, otherwise create().
1521 		 */
1522 		int must_be_dir = pn_fixslash(&pn);	/* trailing '/'? */
1523 
1524 		if (why == CRMKDIR)
1525 			/*
1526 			 * N.B., if vn_createat() ever requests
1527 			 * case-insensitive behavior then it will need
1528 			 * to be passed to VOP_MKDIR().  VOP_CREATE()
1529 			 * will already get it via "flag"
1530 			 */
1531 			error = VOP_MKDIR(dvp, pn.pn_path, vap, vpp, CRED(),
1532 			    NULL, 0, NULL);
1533 		else if (!must_be_dir)
1534 			error = VOP_CREATE(dvp, pn.pn_path, vap,
1535 			    excl, mode, vpp, CRED(), flag, NULL, NULL);
1536 		else
1537 			error = ENOTDIR;
1538 	}
1539 
1540 out:
1541 
1542 	if (auditing)
1543 		audit_vncreate_finish(*vpp, error);
1544 	if (in_crit) {
1545 		nbl_end_crit(vp);
1546 		in_crit = 0;
1547 	}
1548 	if (vp != NULL) {
1549 		VN_RELE(vp);
1550 		vp = NULL;
1551 	}
1552 	pn_free(&pn);
1553 	VN_RELE(dvp);
1554 	/*
1555 	 * The following clause was added to handle a problem
1556 	 * with NFS consistency.  It is possible that a lookup
1557 	 * of the file to be created succeeded, but the file
1558 	 * itself doesn't actually exist on the server.  This
1559 	 * is chiefly due to the DNLC containing an entry for
1560 	 * the file which has been removed on the server.  In
1561 	 * this case, we just start over.  If there was some
1562 	 * other cause for the ESTALE error, then the lookup
1563 	 * of the file will fail and the error will be returned
1564 	 * above instead of looping around from here.
1565 	 */
1566 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1567 		goto top;
1568 	return (error);
1569 }
1570 
1571 int
1572 vn_link(char *from, char *to, enum uio_seg seg)
1573 {
1574 	return (vn_linkat(NULL, from, NO_FOLLOW, NULL, to, seg));
1575 }
1576 
1577 int
1578 vn_linkat(vnode_t *fstartvp, char *from, enum symfollow follow,
1579     vnode_t *tstartvp, char *to, enum uio_seg seg)
1580 {
1581 	struct vnode *fvp;		/* from vnode ptr */
1582 	struct vnode *tdvp;		/* to directory vnode ptr */
1583 	struct pathname pn;
1584 	int error;
1585 	struct vattr vattr;
1586 	dev_t fsid;
1587 	int estale_retry = 0;
1588 	uint32_t auditing = AU_AUDITING();
1589 
1590 top:
1591 	fvp = tdvp = NULL;
1592 	if (error = pn_get(to, seg, &pn))
1593 		return (error);
1594 	if (auditing && fstartvp != NULL)
1595 		audit_setfsat_path(1);
1596 	if (error = lookupnameat(from, seg, follow, NULLVPP, &fvp, fstartvp))
1597 		goto out;
1598 	if (auditing && tstartvp != NULL)
1599 		audit_setfsat_path(3);
1600 	if (error = lookuppnat(&pn, NULL, NO_FOLLOW, &tdvp, NULLVPP, tstartvp))
1601 		goto out;
1602 	/*
1603 	 * Make sure both source vnode and target directory vnode are
1604 	 * in the same vfs and that it is writeable.
1605 	 */
1606 	vattr.va_mask = AT_FSID;
1607 	if (error = VOP_GETATTR(fvp, &vattr, 0, CRED(), NULL))
1608 		goto out;
1609 	fsid = vattr.va_fsid;
1610 	vattr.va_mask = AT_FSID;
1611 	if (error = VOP_GETATTR(tdvp, &vattr, 0, CRED(), NULL))
1612 		goto out;
1613 	if (fsid != vattr.va_fsid) {
1614 		error = EXDEV;
1615 		goto out;
1616 	}
1617 	if (tdvp->v_vfsp->vfs_flag & VFS_RDONLY) {
1618 		error = EROFS;
1619 		goto out;
1620 	}
1621 	/*
1622 	 * Do the link.
1623 	 */
1624 	(void) pn_fixslash(&pn);
1625 	error = VOP_LINK(tdvp, fvp, pn.pn_path, CRED(), NULL, 0);
1626 out:
1627 	pn_free(&pn);
1628 	if (fvp)
1629 		VN_RELE(fvp);
1630 	if (tdvp)
1631 		VN_RELE(tdvp);
1632 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1633 		goto top;
1634 	return (error);
1635 }
1636 
1637 int
1638 vn_rename(char *from, char *to, enum uio_seg seg)
1639 {
1640 	return (vn_renameat(NULL, from, NULL, to, seg));
1641 }
1642 
1643 int
1644 vn_renameat(vnode_t *fdvp, char *fname, vnode_t *tdvp,
1645 		char *tname, enum uio_seg seg)
1646 {
1647 	int error;
1648 	struct vattr vattr;
1649 	struct pathname fpn;		/* from pathname */
1650 	struct pathname tpn;		/* to pathname */
1651 	dev_t fsid;
1652 	int in_crit_src, in_crit_targ;
1653 	vnode_t *fromvp, *fvp;
1654 	vnode_t *tovp, *targvp;
1655 	int estale_retry = 0;
1656 	uint32_t auditing = AU_AUDITING();
1657 
1658 top:
1659 	fvp = fromvp = tovp = targvp = NULL;
1660 	in_crit_src = in_crit_targ = 0;
1661 	/*
1662 	 * Get to and from pathnames.
1663 	 */
1664 	if (error = pn_get(fname, seg, &fpn))
1665 		return (error);
1666 	if (error = pn_get(tname, seg, &tpn)) {
1667 		pn_free(&fpn);
1668 		return (error);
1669 	}
1670 
1671 	/*
1672 	 * First we need to resolve the correct directories
1673 	 * The passed in directories may only be a starting point,
1674 	 * but we need the real directories the file(s) live in.
1675 	 * For example the fname may be something like usr/lib/sparc
1676 	 * and we were passed in the / directory, but we need to
1677 	 * use the lib directory for the rename.
1678 	 */
1679 
1680 	if (auditing && fdvp != NULL)
1681 		audit_setfsat_path(1);
1682 	/*
1683 	 * Lookup to and from directories.
1684 	 */
1685 	if (error = lookuppnat(&fpn, NULL, NO_FOLLOW, &fromvp, &fvp, fdvp)) {
1686 		goto out;
1687 	}
1688 
1689 	/*
1690 	 * Make sure there is an entry.
1691 	 */
1692 	if (fvp == NULL) {
1693 		error = ENOENT;
1694 		goto out;
1695 	}
1696 
1697 	if (auditing && tdvp != NULL)
1698 		audit_setfsat_path(3);
1699 	if (error = lookuppnat(&tpn, NULL, NO_FOLLOW, &tovp, &targvp, tdvp)) {
1700 		goto out;
1701 	}
1702 
1703 	/*
1704 	 * Make sure both the from vnode directory and the to directory
1705 	 * are in the same vfs and the to directory is writable.
1706 	 * We check fsid's, not vfs pointers, so loopback fs works.
1707 	 */
1708 	if (fromvp != tovp) {
1709 		vattr.va_mask = AT_FSID;
1710 		if (error = VOP_GETATTR(fromvp, &vattr, 0, CRED(), NULL))
1711 			goto out;
1712 		fsid = vattr.va_fsid;
1713 		vattr.va_mask = AT_FSID;
1714 		if (error = VOP_GETATTR(tovp, &vattr, 0, CRED(), NULL))
1715 			goto out;
1716 		if (fsid != vattr.va_fsid) {
1717 			error = EXDEV;
1718 			goto out;
1719 		}
1720 	}
1721 
1722 	if (tovp->v_vfsp->vfs_flag & VFS_RDONLY) {
1723 		error = EROFS;
1724 		goto out;
1725 	}
1726 
1727 	if (targvp && (fvp != targvp)) {
1728 		nbl_start_crit(targvp, RW_READER);
1729 		in_crit_targ = 1;
1730 		if (nbl_conflict(targvp, NBL_REMOVE, 0, 0, 0, NULL)) {
1731 			error = EACCES;
1732 			goto out;
1733 		}
1734 	}
1735 
1736 	if (nbl_need_check(fvp)) {
1737 		nbl_start_crit(fvp, RW_READER);
1738 		in_crit_src = 1;
1739 		if (nbl_conflict(fvp, NBL_RENAME, 0, 0, 0, NULL)) {
1740 			error = EACCES;
1741 			goto out;
1742 		}
1743 	}
1744 
1745 	/*
1746 	 * Do the rename.
1747 	 */
1748 	(void) pn_fixslash(&tpn);
1749 	error = VOP_RENAME(fromvp, fpn.pn_path, tovp, tpn.pn_path, CRED(),
1750 	    NULL, 0);
1751 
1752 out:
1753 	pn_free(&fpn);
1754 	pn_free(&tpn);
1755 	if (in_crit_src)
1756 		nbl_end_crit(fvp);
1757 	if (in_crit_targ)
1758 		nbl_end_crit(targvp);
1759 	if (fromvp)
1760 		VN_RELE(fromvp);
1761 	if (tovp)
1762 		VN_RELE(tovp);
1763 	if (targvp)
1764 		VN_RELE(targvp);
1765 	if (fvp)
1766 		VN_RELE(fvp);
1767 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1768 		goto top;
1769 	return (error);
1770 }
1771 
1772 /*
1773  * Remove a file or directory.
1774  */
1775 int
1776 vn_remove(char *fnamep, enum uio_seg seg, enum rm dirflag)
1777 {
1778 	return (vn_removeat(NULL, fnamep, seg, dirflag));
1779 }
1780 
1781 int
1782 vn_removeat(vnode_t *startvp, char *fnamep, enum uio_seg seg, enum rm dirflag)
1783 {
1784 	struct vnode *vp;		/* entry vnode */
1785 	struct vnode *dvp;		/* ptr to parent dir vnode */
1786 	struct vnode *coveredvp;
1787 	struct pathname pn;		/* name of entry */
1788 	enum vtype vtype;
1789 	int error;
1790 	struct vfs *vfsp;
1791 	struct vfs *dvfsp;	/* ptr to parent dir vfs */
1792 	int in_crit = 0;
1793 	int estale_retry = 0;
1794 
1795 top:
1796 	if (error = pn_get(fnamep, seg, &pn))
1797 		return (error);
1798 	dvp = vp = NULL;
1799 	if (error = lookuppnat(&pn, NULL, NO_FOLLOW, &dvp, &vp, startvp)) {
1800 		pn_free(&pn);
1801 		if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1802 			goto top;
1803 		return (error);
1804 	}
1805 
1806 	/*
1807 	 * Make sure there is an entry.
1808 	 */
1809 	if (vp == NULL) {
1810 		error = ENOENT;
1811 		goto out;
1812 	}
1813 
1814 	vfsp = vp->v_vfsp;
1815 	dvfsp = dvp->v_vfsp;
1816 
1817 	/*
1818 	 * If the named file is the root of a mounted filesystem, fail,
1819 	 * unless it's marked unlinkable.  In that case, unmount the
1820 	 * filesystem and proceed to unlink the covered vnode.  (If the
1821 	 * covered vnode is a directory, use rmdir instead of unlink,
1822 	 * to avoid file system corruption.)
1823 	 */
1824 	if (vp->v_flag & VROOT) {
1825 		if ((vfsp->vfs_flag & VFS_UNLINKABLE) == 0) {
1826 			error = EBUSY;
1827 			goto out;
1828 		}
1829 
1830 		/*
1831 		 * Namefs specific code starts here.
1832 		 */
1833 
1834 		if (dirflag == RMDIRECTORY) {
1835 			/*
1836 			 * User called rmdir(2) on a file that has
1837 			 * been namefs mounted on top of.  Since
1838 			 * namefs doesn't allow directories to
1839 			 * be mounted on other files we know
1840 			 * vp is not of type VDIR so fail to operation.
1841 			 */
1842 			error = ENOTDIR;
1843 			goto out;
1844 		}
1845 
1846 		/*
1847 		 * If VROOT is still set after grabbing vp->v_lock,
1848 		 * noone has finished nm_unmount so far and coveredvp
1849 		 * is valid.
1850 		 * If we manage to grab vn_vfswlock(coveredvp) before releasing
1851 		 * vp->v_lock, any race window is eliminated.
1852 		 */
1853 
1854 		mutex_enter(&vp->v_lock);
1855 		if ((vp->v_flag & VROOT) == 0) {
1856 			/* Someone beat us to the unmount */
1857 			mutex_exit(&vp->v_lock);
1858 			error = EBUSY;
1859 			goto out;
1860 		}
1861 		vfsp = vp->v_vfsp;
1862 		coveredvp = vfsp->vfs_vnodecovered;
1863 		ASSERT(coveredvp);
1864 		/*
1865 		 * Note: Implementation of vn_vfswlock shows that ordering of
1866 		 * v_lock / vn_vfswlock is not an issue here.
1867 		 */
1868 		error = vn_vfswlock(coveredvp);
1869 		mutex_exit(&vp->v_lock);
1870 
1871 		if (error)
1872 			goto out;
1873 
1874 		VN_HOLD(coveredvp);
1875 		VN_RELE(vp);
1876 		error = dounmount(vfsp, 0, CRED());
1877 
1878 		/*
1879 		 * Unmounted the namefs file system; now get
1880 		 * the object it was mounted over.
1881 		 */
1882 		vp = coveredvp;
1883 		/*
1884 		 * If namefs was mounted over a directory, then
1885 		 * we want to use rmdir() instead of unlink().
1886 		 */
1887 		if (vp->v_type == VDIR)
1888 			dirflag = RMDIRECTORY;
1889 
1890 		if (error)
1891 			goto out;
1892 	}
1893 
1894 	/*
1895 	 * Make sure filesystem is writeable.
1896 	 * We check the parent directory's vfs in case this is an lofs vnode.
1897 	 */
1898 	if (dvfsp && dvfsp->vfs_flag & VFS_RDONLY) {
1899 		error = EROFS;
1900 		goto out;
1901 	}
1902 
1903 	vtype = vp->v_type;
1904 
1905 	/*
1906 	 * If there is the possibility of an nbmand share reservation, make
1907 	 * sure it's okay to remove the file.  Keep a reference to the
1908 	 * vnode, so that we can exit the nbl critical region after
1909 	 * calling VOP_REMOVE.
1910 	 * If there is no possibility of an nbmand share reservation,
1911 	 * release the vnode reference now.  Filesystems like NFS may
1912 	 * behave differently if there is an extra reference, so get rid of
1913 	 * this one.  Fortunately, we can't have nbmand mounts on NFS
1914 	 * filesystems.
1915 	 */
1916 	if (nbl_need_check(vp)) {
1917 		nbl_start_crit(vp, RW_READER);
1918 		in_crit = 1;
1919 		if (nbl_conflict(vp, NBL_REMOVE, 0, 0, 0, NULL)) {
1920 			error = EACCES;
1921 			goto out;
1922 		}
1923 	} else {
1924 		VN_RELE(vp);
1925 		vp = NULL;
1926 	}
1927 
1928 	if (dirflag == RMDIRECTORY) {
1929 		/*
1930 		 * Caller is using rmdir(2), which can only be applied to
1931 		 * directories.
1932 		 */
1933 		if (vtype != VDIR) {
1934 			error = ENOTDIR;
1935 		} else {
1936 			vnode_t *cwd;
1937 			proc_t *pp = curproc;
1938 
1939 			mutex_enter(&pp->p_lock);
1940 			cwd = PTOU(pp)->u_cdir;
1941 			VN_HOLD(cwd);
1942 			mutex_exit(&pp->p_lock);
1943 			error = VOP_RMDIR(dvp, pn.pn_path, cwd, CRED(),
1944 			    NULL, 0);
1945 			VN_RELE(cwd);
1946 		}
1947 	} else {
1948 		/*
1949 		 * Unlink(2) can be applied to anything.
1950 		 */
1951 		error = VOP_REMOVE(dvp, pn.pn_path, CRED(), NULL, 0);
1952 	}
1953 
1954 out:
1955 	pn_free(&pn);
1956 	if (in_crit) {
1957 		nbl_end_crit(vp);
1958 		in_crit = 0;
1959 	}
1960 	if (vp != NULL)
1961 		VN_RELE(vp);
1962 	if (dvp != NULL)
1963 		VN_RELE(dvp);
1964 	if ((error == ESTALE) && fs_need_estale_retry(estale_retry++))
1965 		goto top;
1966 	return (error);
1967 }
1968 
1969 /*
1970  * Utility function to compare equality of vnodes.
1971  * Compare the underlying real vnodes, if there are underlying vnodes.
1972  * This is a more thorough comparison than the VN_CMP() macro provides.
1973  */
1974 int
1975 vn_compare(vnode_t *vp1, vnode_t *vp2)
1976 {
1977 	vnode_t *realvp;
1978 
1979 	if (vp1 != NULL && VOP_REALVP(vp1, &realvp, NULL) == 0)
1980 		vp1 = realvp;
1981 	if (vp2 != NULL && VOP_REALVP(vp2, &realvp, NULL) == 0)
1982 		vp2 = realvp;
1983 	return (VN_CMP(vp1, vp2));
1984 }
1985 
1986 /*
1987  * The number of locks to hash into.  This value must be a power
1988  * of 2 minus 1 and should probably also be prime.
1989  */
1990 #define	NUM_BUCKETS	1023
1991 
1992 struct  vn_vfslocks_bucket {
1993 	kmutex_t vb_lock;
1994 	vn_vfslocks_entry_t *vb_list;
1995 	char pad[64 - sizeof (kmutex_t) - sizeof (void *)];
1996 };
1997 
1998 /*
1999  * Total number of buckets will be NUM_BUCKETS + 1 .
2000  */
2001 
2002 #pragma	align	64(vn_vfslocks_buckets)
2003 static	struct vn_vfslocks_bucket	vn_vfslocks_buckets[NUM_BUCKETS + 1];
2004 
2005 #define	VN_VFSLOCKS_SHIFT	9
2006 
2007 #define	VN_VFSLOCKS_HASH(vfsvpptr)	\
2008 	((((intptr_t)(vfsvpptr)) >> VN_VFSLOCKS_SHIFT) & NUM_BUCKETS)
2009 
2010 /*
2011  * vn_vfslocks_getlock() uses an HASH scheme to generate
2012  * rwstlock using vfs/vnode pointer passed to it.
2013  *
2014  * vn_vfslocks_rele() releases a reference in the
2015  * HASH table which allows the entry allocated by
2016  * vn_vfslocks_getlock() to be freed at a later
2017  * stage when the refcount drops to zero.
2018  */
2019 
2020 vn_vfslocks_entry_t *
2021 vn_vfslocks_getlock(void *vfsvpptr)
2022 {
2023 	struct vn_vfslocks_bucket *bp;
2024 	vn_vfslocks_entry_t *vep;
2025 	vn_vfslocks_entry_t *tvep;
2026 
2027 	ASSERT(vfsvpptr != NULL);
2028 	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vfsvpptr)];
2029 
2030 	mutex_enter(&bp->vb_lock);
2031 	for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
2032 		if (vep->ve_vpvfs == vfsvpptr) {
2033 			vep->ve_refcnt++;
2034 			mutex_exit(&bp->vb_lock);
2035 			return (vep);
2036 		}
2037 	}
2038 	mutex_exit(&bp->vb_lock);
2039 	vep = kmem_alloc(sizeof (*vep), KM_SLEEP);
2040 	rwst_init(&vep->ve_lock, NULL, RW_DEFAULT, NULL);
2041 	vep->ve_vpvfs = (char *)vfsvpptr;
2042 	vep->ve_refcnt = 1;
2043 	mutex_enter(&bp->vb_lock);
2044 	for (tvep = bp->vb_list; tvep != NULL; tvep = tvep->ve_next) {
2045 		if (tvep->ve_vpvfs == vfsvpptr) {
2046 			tvep->ve_refcnt++;
2047 			mutex_exit(&bp->vb_lock);
2048 
2049 			/*
2050 			 * There is already an entry in the hash
2051 			 * destroy what we just allocated.
2052 			 */
2053 			rwst_destroy(&vep->ve_lock);
2054 			kmem_free(vep, sizeof (*vep));
2055 			return (tvep);
2056 		}
2057 	}
2058 	vep->ve_next = bp->vb_list;
2059 	bp->vb_list = vep;
2060 	mutex_exit(&bp->vb_lock);
2061 	return (vep);
2062 }
2063 
2064 void
2065 vn_vfslocks_rele(vn_vfslocks_entry_t *vepent)
2066 {
2067 	struct vn_vfslocks_bucket *bp;
2068 	vn_vfslocks_entry_t *vep;
2069 	vn_vfslocks_entry_t *pvep;
2070 
2071 	ASSERT(vepent != NULL);
2072 	ASSERT(vepent->ve_vpvfs != NULL);
2073 
2074 	bp = &vn_vfslocks_buckets[VN_VFSLOCKS_HASH(vepent->ve_vpvfs)];
2075 
2076 	mutex_enter(&bp->vb_lock);
2077 	vepent->ve_refcnt--;
2078 
2079 	if ((int32_t)vepent->ve_refcnt < 0)
2080 		cmn_err(CE_PANIC, "vn_vfslocks_rele: refcount negative");
2081 
2082 	if (vepent->ve_refcnt == 0) {
2083 		for (vep = bp->vb_list; vep != NULL; vep = vep->ve_next) {
2084 			if (vep->ve_vpvfs == vepent->ve_vpvfs) {
2085 				if (bp->vb_list == vep)
2086 					bp->vb_list = vep->ve_next;
2087 				else {
2088 					/* LINTED */
2089 					pvep->ve_next = vep->ve_next;
2090 				}
2091 				mutex_exit(&bp->vb_lock);
2092 				rwst_destroy(&vep->ve_lock);
2093 				kmem_free(vep, sizeof (*vep));
2094 				return;
2095 			}
2096 			pvep = vep;
2097 		}
2098 		cmn_err(CE_PANIC, "vn_vfslocks_rele: vp/vfs not found");
2099 	}
2100 	mutex_exit(&bp->vb_lock);
2101 }
2102 
2103 /*
2104  * vn_vfswlock_wait is used to implement a lock which is logically a writers
2105  * lock protecting the v_vfsmountedhere field.
2106  * vn_vfswlock_wait has been modified to be similar to vn_vfswlock,
2107  * except that it blocks to acquire the lock VVFSLOCK.
2108  *
2109  * traverse() and routines re-implementing part of traverse (e.g. autofs)
2110  * need to hold this lock. mount(), vn_rename(), vn_remove() and so on
2111  * need the non-blocking version of the writers lock i.e. vn_vfswlock
2112  */
2113 int
2114 vn_vfswlock_wait(vnode_t *vp)
2115 {
2116 	int retval;
2117 	vn_vfslocks_entry_t *vpvfsentry;
2118 	ASSERT(vp != NULL);
2119 
2120 	vpvfsentry = vn_vfslocks_getlock(vp);
2121 	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_WRITER);
2122 
2123 	if (retval == EINTR) {
2124 		vn_vfslocks_rele(vpvfsentry);
2125 		return (EINTR);
2126 	}
2127 	return (retval);
2128 }
2129 
2130 int
2131 vn_vfsrlock_wait(vnode_t *vp)
2132 {
2133 	int retval;
2134 	vn_vfslocks_entry_t *vpvfsentry;
2135 	ASSERT(vp != NULL);
2136 
2137 	vpvfsentry = vn_vfslocks_getlock(vp);
2138 	retval = rwst_enter_sig(&vpvfsentry->ve_lock, RW_READER);
2139 
2140 	if (retval == EINTR) {
2141 		vn_vfslocks_rele(vpvfsentry);
2142 		return (EINTR);
2143 	}
2144 
2145 	return (retval);
2146 }
2147 
2148 
2149 /*
2150  * vn_vfswlock is used to implement a lock which is logically a writers lock
2151  * protecting the v_vfsmountedhere field.
2152  */
2153 int
2154 vn_vfswlock(vnode_t *vp)
2155 {
2156 	vn_vfslocks_entry_t *vpvfsentry;
2157 
2158 	/*
2159 	 * If vp is NULL then somebody is trying to lock the covered vnode
2160 	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
2161 	 * only happen when unmounting /.  Since that operation will fail
2162 	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
2163 	 */
2164 	if (vp == NULL)
2165 		return (EBUSY);
2166 
2167 	vpvfsentry = vn_vfslocks_getlock(vp);
2168 
2169 	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_WRITER))
2170 		return (0);
2171 
2172 	vn_vfslocks_rele(vpvfsentry);
2173 	return (EBUSY);
2174 }
2175 
2176 int
2177 vn_vfsrlock(vnode_t *vp)
2178 {
2179 	vn_vfslocks_entry_t *vpvfsentry;
2180 
2181 	/*
2182 	 * If vp is NULL then somebody is trying to lock the covered vnode
2183 	 * of /.  (vfs_vnodecovered is NULL for /).  This situation will
2184 	 * only happen when unmounting /.  Since that operation will fail
2185 	 * anyway, return EBUSY here instead of in VFS_UNMOUNT.
2186 	 */
2187 	if (vp == NULL)
2188 		return (EBUSY);
2189 
2190 	vpvfsentry = vn_vfslocks_getlock(vp);
2191 
2192 	if (rwst_tryenter(&vpvfsentry->ve_lock, RW_READER))
2193 		return (0);
2194 
2195 	vn_vfslocks_rele(vpvfsentry);
2196 	return (EBUSY);
2197 }
2198 
2199 void
2200 vn_vfsunlock(vnode_t *vp)
2201 {
2202 	vn_vfslocks_entry_t *vpvfsentry;
2203 
2204 	/*
2205 	 * ve_refcnt needs to be decremented twice.
2206 	 * 1. To release refernce after a call to vn_vfslocks_getlock()
2207 	 * 2. To release the reference from the locking routines like
2208 	 *    vn_vfsrlock/vn_vfswlock etc,.
2209 	 */
2210 	vpvfsentry = vn_vfslocks_getlock(vp);
2211 	vn_vfslocks_rele(vpvfsentry);
2212 
2213 	rwst_exit(&vpvfsentry->ve_lock);
2214 	vn_vfslocks_rele(vpvfsentry);
2215 }
2216 
2217 int
2218 vn_vfswlock_held(vnode_t *vp)
2219 {
2220 	int held;
2221 	vn_vfslocks_entry_t *vpvfsentry;
2222 
2223 	ASSERT(vp != NULL);
2224 
2225 	vpvfsentry = vn_vfslocks_getlock(vp);
2226 	held = rwst_lock_held(&vpvfsentry->ve_lock, RW_WRITER);
2227 
2228 	vn_vfslocks_rele(vpvfsentry);
2229 	return (held);
2230 }
2231 
2232 
2233 int
2234 vn_make_ops(
2235 	const char *name,			/* Name of file system */
2236 	const fs_operation_def_t *templ,	/* Operation specification */
2237 	vnodeops_t **actual)			/* Return the vnodeops */
2238 {
2239 	int unused_ops;
2240 	int error;
2241 
2242 	*actual = (vnodeops_t *)kmem_alloc(sizeof (vnodeops_t), KM_SLEEP);
2243 
2244 	(*actual)->vnop_name = name;
2245 
2246 	error = fs_build_vector(*actual, &unused_ops, vn_ops_table, templ);
2247 	if (error) {
2248 		kmem_free(*actual, sizeof (vnodeops_t));
2249 	}
2250 
2251 #if DEBUG
2252 	if (unused_ops != 0)
2253 		cmn_err(CE_WARN, "vn_make_ops: %s: %d operations supplied "
2254 		    "but not used", name, unused_ops);
2255 #endif
2256 
2257 	return (error);
2258 }
2259 
2260 /*
2261  * Free the vnodeops created as a result of vn_make_ops()
2262  */
2263 void
2264 vn_freevnodeops(vnodeops_t *vnops)
2265 {
2266 	kmem_free(vnops, sizeof (vnodeops_t));
2267 }
2268 
2269 /*
2270  * Vnode cache.
2271  */
2272 
2273 /* ARGSUSED */
2274 static int
2275 vn_cache_constructor(void *buf, void *cdrarg, int kmflags)
2276 {
2277 	struct vnode *vp;
2278 
2279 	vp = buf;
2280 
2281 	mutex_init(&vp->v_lock, NULL, MUTEX_DEFAULT, NULL);
2282 	mutex_init(&vp->v_vsd_lock, NULL, MUTEX_DEFAULT, NULL);
2283 	cv_init(&vp->v_cv, NULL, CV_DEFAULT, NULL);
2284 	rw_init(&vp->v_nbllock, NULL, RW_DEFAULT, NULL);
2285 	vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
2286 	vp->v_path = NULL;
2287 	vp->v_mpssdata = NULL;
2288 	vp->v_vsd = NULL;
2289 	vp->v_fopdata = NULL;
2290 
2291 	return (0);
2292 }
2293 
2294 /* ARGSUSED */
2295 static void
2296 vn_cache_destructor(void *buf, void *cdrarg)
2297 {
2298 	struct vnode *vp;
2299 
2300 	vp = buf;
2301 
2302 	rw_destroy(&vp->v_nbllock);
2303 	cv_destroy(&vp->v_cv);
2304 	mutex_destroy(&vp->v_vsd_lock);
2305 	mutex_destroy(&vp->v_lock);
2306 }
2307 
2308 void
2309 vn_create_cache(void)
2310 {
2311 	/* LINTED */
2312 	ASSERT((1 << VNODE_ALIGN_LOG2) ==
2313 	    P2ROUNDUP(sizeof (struct vnode), VNODE_ALIGN));
2314 	vn_cache = kmem_cache_create("vn_cache", sizeof (struct vnode),
2315 	    VNODE_ALIGN, vn_cache_constructor, vn_cache_destructor, NULL, NULL,
2316 	    NULL, 0);
2317 }
2318 
2319 void
2320 vn_destroy_cache(void)
2321 {
2322 	kmem_cache_destroy(vn_cache);
2323 }
2324 
2325 /*
2326  * Used by file systems when fs-specific nodes (e.g., ufs inodes) are
2327  * cached by the file system and vnodes remain associated.
2328  */
2329 void
2330 vn_recycle(vnode_t *vp)
2331 {
2332 	ASSERT(vp->v_pages == NULL);
2333 
2334 	/*
2335 	 * XXX - This really belongs in vn_reinit(), but we have some issues
2336 	 * with the counts.  Best to have it here for clean initialization.
2337 	 */
2338 	vp->v_rdcnt = 0;
2339 	vp->v_wrcnt = 0;
2340 	vp->v_mmap_read = 0;
2341 	vp->v_mmap_write = 0;
2342 
2343 	/*
2344 	 * If FEM was in use, make sure everything gets cleaned up
2345 	 * NOTE: vp->v_femhead is initialized to NULL in the vnode
2346 	 * constructor.
2347 	 */
2348 	if (vp->v_femhead) {
2349 		/* XXX - There should be a free_femhead() that does all this */
2350 		ASSERT(vp->v_femhead->femh_list == NULL);
2351 		mutex_destroy(&vp->v_femhead->femh_lock);
2352 		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
2353 		vp->v_femhead = NULL;
2354 	}
2355 	if (vp->v_path) {
2356 		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
2357 		vp->v_path = NULL;
2358 	}
2359 
2360 	if (vp->v_fopdata != NULL) {
2361 		free_fopdata(vp);
2362 	}
2363 	vp->v_mpssdata = NULL;
2364 	vsd_free(vp);
2365 }
2366 
2367 /*
2368  * Used to reset the vnode fields including those that are directly accessible
2369  * as well as those which require an accessor function.
2370  *
2371  * Does not initialize:
2372  *	synchronization objects: v_lock, v_vsd_lock, v_nbllock, v_cv
2373  *	v_data (since FS-nodes and vnodes point to each other and should
2374  *		be updated simultaneously)
2375  *	v_op (in case someone needs to make a VOP call on this object)
2376  */
2377 void
2378 vn_reinit(vnode_t *vp)
2379 {
2380 	vp->v_count = 1;
2381 	vp->v_count_dnlc = 0;
2382 	vp->v_vfsp = NULL;
2383 	vp->v_stream = NULL;
2384 	vp->v_vfsmountedhere = NULL;
2385 	vp->v_flag = 0;
2386 	vp->v_type = VNON;
2387 	vp->v_rdev = NODEV;
2388 
2389 	vp->v_filocks = NULL;
2390 	vp->v_shrlocks = NULL;
2391 	vp->v_pages = NULL;
2392 
2393 	vp->v_locality = NULL;
2394 	vp->v_xattrdir = NULL;
2395 
2396 	/* Handles v_femhead, v_path, and the r/w/map counts */
2397 	vn_recycle(vp);
2398 }
2399 
2400 vnode_t *
2401 vn_alloc(int kmflag)
2402 {
2403 	vnode_t *vp;
2404 
2405 	vp = kmem_cache_alloc(vn_cache, kmflag);
2406 
2407 	if (vp != NULL) {
2408 		vp->v_femhead = NULL;	/* Must be done before vn_reinit() */
2409 		vp->v_fopdata = NULL;
2410 		vn_reinit(vp);
2411 	}
2412 
2413 	return (vp);
2414 }
2415 
2416 void
2417 vn_free(vnode_t *vp)
2418 {
2419 	ASSERT(vp->v_shrlocks == NULL);
2420 	ASSERT(vp->v_filocks == NULL);
2421 
2422 	/*
2423 	 * Some file systems call vn_free() with v_count of zero,
2424 	 * some with v_count of 1.  In any case, the value should
2425 	 * never be anything else.
2426 	 */
2427 	ASSERT((vp->v_count == 0) || (vp->v_count == 1));
2428 	ASSERT(vp->v_count_dnlc == 0);
2429 	if (vp->v_path != NULL) {
2430 		kmem_free(vp->v_path, strlen(vp->v_path) + 1);
2431 		vp->v_path = NULL;
2432 	}
2433 
2434 	/* If FEM was in use, make sure everything gets cleaned up */
2435 	if (vp->v_femhead) {
2436 		/* XXX - There should be a free_femhead() that does all this */
2437 		ASSERT(vp->v_femhead->femh_list == NULL);
2438 		mutex_destroy(&vp->v_femhead->femh_lock);
2439 		kmem_free(vp->v_femhead, sizeof (*(vp->v_femhead)));
2440 		vp->v_femhead = NULL;
2441 	}
2442 
2443 	if (vp->v_fopdata != NULL) {
2444 		free_fopdata(vp);
2445 	}
2446 	vp->v_mpssdata = NULL;
2447 	vsd_free(vp);
2448 	kmem_cache_free(vn_cache, vp);
2449 }
2450 
2451 /*
2452  * vnode status changes, should define better states than 1, 0.
2453  */
2454 void
2455 vn_reclaim(vnode_t *vp)
2456 {
2457 	vfs_t   *vfsp = vp->v_vfsp;
2458 
2459 	if (vfsp == NULL ||
2460 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2461 		return;
2462 	}
2463 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_RECLAIMED);
2464 }
2465 
2466 void
2467 vn_idle(vnode_t *vp)
2468 {
2469 	vfs_t   *vfsp = vp->v_vfsp;
2470 
2471 	if (vfsp == NULL ||
2472 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2473 		return;
2474 	}
2475 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_IDLED);
2476 }
2477 void
2478 vn_exists(vnode_t *vp)
2479 {
2480 	vfs_t   *vfsp = vp->v_vfsp;
2481 
2482 	if (vfsp == NULL ||
2483 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2484 		return;
2485 	}
2486 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_EXISTS);
2487 }
2488 
2489 void
2490 vn_invalid(vnode_t *vp)
2491 {
2492 	vfs_t   *vfsp = vp->v_vfsp;
2493 
2494 	if (vfsp == NULL ||
2495 	    vfsp->vfs_implp == NULL || vfsp->vfs_femhead == NULL) {
2496 		return;
2497 	}
2498 	(void) VFS_VNSTATE(vfsp, vp, VNTRANS_DESTROYED);
2499 }
2500 
2501 /* Vnode event notification */
2502 
2503 int
2504 vnevent_support(vnode_t *vp, caller_context_t *ct)
2505 {
2506 	if (vp == NULL)
2507 		return (EINVAL);
2508 
2509 	return (VOP_VNEVENT(vp, VE_SUPPORT, NULL, NULL, ct));
2510 }
2511 
2512 void
2513 vnevent_rename_src(vnode_t *vp, vnode_t *dvp, char *name, caller_context_t *ct)
2514 {
2515 	if (vp == NULL || vp->v_femhead == NULL) {
2516 		return;
2517 	}
2518 	(void) VOP_VNEVENT(vp, VE_RENAME_SRC, dvp, name, ct);
2519 }
2520 
2521 void
2522 vnevent_rename_dest(vnode_t *vp, vnode_t *dvp, char *name,
2523     caller_context_t *ct)
2524 {
2525 	if (vp == NULL || vp->v_femhead == NULL) {
2526 		return;
2527 	}
2528 	(void) VOP_VNEVENT(vp, VE_RENAME_DEST, dvp, name, ct);
2529 }
2530 
2531 void
2532 vnevent_rename_dest_dir(vnode_t *vp, caller_context_t *ct)
2533 {
2534 	if (vp == NULL || vp->v_femhead == NULL) {
2535 		return;
2536 	}
2537 	(void) VOP_VNEVENT(vp, VE_RENAME_DEST_DIR, NULL, NULL, ct);
2538 }
2539 
2540 void
2541 vnevent_remove(vnode_t *vp, vnode_t *dvp, char *name, caller_context_t *ct)
2542 {
2543 	if (vp == NULL || vp->v_femhead == NULL) {
2544 		return;
2545 	}
2546 	(void) VOP_VNEVENT(vp, VE_REMOVE, dvp, name, ct);
2547 }
2548 
2549 void
2550 vnevent_rmdir(vnode_t *vp, vnode_t *dvp, char *name, caller_context_t *ct)
2551 {
2552 	if (vp == NULL || vp->v_femhead == NULL) {
2553 		return;
2554 	}
2555 	(void) VOP_VNEVENT(vp, VE_RMDIR, dvp, name, ct);
2556 }
2557 
2558 void
2559 vnevent_create(vnode_t *vp, caller_context_t *ct)
2560 {
2561 	if (vp == NULL || vp->v_femhead == NULL) {
2562 		return;
2563 	}
2564 	(void) VOP_VNEVENT(vp, VE_CREATE, NULL, NULL, ct);
2565 }
2566 
2567 void
2568 vnevent_link(vnode_t *vp, caller_context_t *ct)
2569 {
2570 	if (vp == NULL || vp->v_femhead == NULL) {
2571 		return;
2572 	}
2573 	(void) VOP_VNEVENT(vp, VE_LINK, NULL, NULL, ct);
2574 }
2575 
2576 void
2577 vnevent_mountedover(vnode_t *vp, caller_context_t *ct)
2578 {
2579 	if (vp == NULL || vp->v_femhead == NULL) {
2580 		return;
2581 	}
2582 	(void) VOP_VNEVENT(vp, VE_MOUNTEDOVER, NULL, NULL, ct);
2583 }
2584 
2585 /*
2586  * Vnode accessors.
2587  */
2588 
2589 int
2590 vn_is_readonly(vnode_t *vp)
2591 {
2592 	return (vp->v_vfsp->vfs_flag & VFS_RDONLY);
2593 }
2594 
2595 int
2596 vn_has_flocks(vnode_t *vp)
2597 {
2598 	return (vp->v_filocks != NULL);
2599 }
2600 
2601 int
2602 vn_has_mandatory_locks(vnode_t *vp, int mode)
2603 {
2604 	return ((vp->v_filocks != NULL) && (MANDLOCK(vp, mode)));
2605 }
2606 
2607 int
2608 vn_has_cached_data(vnode_t *vp)
2609 {
2610 	return (vp->v_pages != NULL);
2611 }
2612 
2613 /*
2614  * Return 0 if the vnode in question shouldn't be permitted into a zone via
2615  * zone_enter(2).
2616  */
2617 int
2618 vn_can_change_zones(vnode_t *vp)
2619 {
2620 	struct vfssw *vswp;
2621 	int allow = 1;
2622 	vnode_t *rvp;
2623 
2624 	if (nfs_global_client_only != 0)
2625 		return (1);
2626 
2627 	/*
2628 	 * We always want to look at the underlying vnode if there is one.
2629 	 */
2630 	if (VOP_REALVP(vp, &rvp, NULL) != 0)
2631 		rvp = vp;
2632 	/*
2633 	 * Some pseudo filesystems (including doorfs) don't actually register
2634 	 * their vfsops_t, so the following may return NULL; we happily let
2635 	 * such vnodes switch zones.
2636 	 */
2637 	vswp = vfs_getvfsswbyvfsops(vfs_getops(rvp->v_vfsp));
2638 	if (vswp != NULL) {
2639 		if (vswp->vsw_flag & VSW_NOTZONESAFE)
2640 			allow = 0;
2641 		vfs_unrefvfssw(vswp);
2642 	}
2643 	return (allow);
2644 }
2645 
2646 /*
2647  * Return nonzero if the vnode is a mount point, zero if not.
2648  */
2649 int
2650 vn_ismntpt(vnode_t *vp)
2651 {
2652 	return (vp->v_vfsmountedhere != NULL);
2653 }
2654 
2655 /* Retrieve the vfs (if any) mounted on this vnode */
2656 vfs_t *
2657 vn_mountedvfs(vnode_t *vp)
2658 {
2659 	return (vp->v_vfsmountedhere);
2660 }
2661 
2662 /*
2663  * Return nonzero if the vnode is referenced by the dnlc, zero if not.
2664  */
2665 int
2666 vn_in_dnlc(vnode_t *vp)
2667 {
2668 	return (vp->v_count_dnlc > 0);
2669 }
2670 
2671 /*
2672  * vn_has_other_opens() checks whether a particular file is opened by more than
2673  * just the caller and whether the open is for read and/or write.
2674  * This routine is for calling after the caller has already called VOP_OPEN()
2675  * and the caller wishes to know if they are the only one with it open for
2676  * the mode(s) specified.
2677  *
2678  * Vnode counts are only kept on regular files (v_type=VREG).
2679  */
2680 int
2681 vn_has_other_opens(
2682 	vnode_t *vp,
2683 	v_mode_t mode)
2684 {
2685 
2686 	ASSERT(vp != NULL);
2687 
2688 	switch (mode) {
2689 	case V_WRITE:
2690 		if (vp->v_wrcnt > 1)
2691 			return (V_TRUE);
2692 		break;
2693 	case V_RDORWR:
2694 		if ((vp->v_rdcnt > 1) || (vp->v_wrcnt > 1))
2695 			return (V_TRUE);
2696 		break;
2697 	case V_RDANDWR:
2698 		if ((vp->v_rdcnt > 1) && (vp->v_wrcnt > 1))
2699 			return (V_TRUE);
2700 		break;
2701 	case V_READ:
2702 		if (vp->v_rdcnt > 1)
2703 			return (V_TRUE);
2704 		break;
2705 	}
2706 
2707 	return (V_FALSE);
2708 }
2709 
2710 /*
2711  * vn_is_opened() checks whether a particular file is opened and
2712  * whether the open is for read and/or write.
2713  *
2714  * Vnode counts are only kept on regular files (v_type=VREG).
2715  */
2716 int
2717 vn_is_opened(
2718 	vnode_t *vp,
2719 	v_mode_t mode)
2720 {
2721 
2722 	ASSERT(vp != NULL);
2723 
2724 	switch (mode) {
2725 	case V_WRITE:
2726 		if (vp->v_wrcnt)
2727 			return (V_TRUE);
2728 		break;
2729 	case V_RDANDWR:
2730 		if (vp->v_rdcnt && vp->v_wrcnt)
2731 			return (V_TRUE);
2732 		break;
2733 	case V_RDORWR:
2734 		if (vp->v_rdcnt || vp->v_wrcnt)
2735 			return (V_TRUE);
2736 		break;
2737 	case V_READ:
2738 		if (vp->v_rdcnt)
2739 			return (V_TRUE);
2740 		break;
2741 	}
2742 
2743 	return (V_FALSE);
2744 }
2745 
2746 /*
2747  * vn_is_mapped() checks whether a particular file is mapped and whether
2748  * the file is mapped read and/or write.
2749  */
2750 int
2751 vn_is_mapped(
2752 	vnode_t *vp,
2753 	v_mode_t mode)
2754 {
2755 
2756 	ASSERT(vp != NULL);
2757 
2758 #if !defined(_LP64)
2759 	switch (mode) {
2760 	/*
2761 	 * The atomic_add_64_nv functions force atomicity in the
2762 	 * case of 32 bit architectures. Otherwise the 64 bit values
2763 	 * require two fetches. The value of the fields may be
2764 	 * (potentially) changed between the first fetch and the
2765 	 * second
2766 	 */
2767 	case V_WRITE:
2768 		if (atomic_add_64_nv((&(vp->v_mmap_write)), 0))
2769 			return (V_TRUE);
2770 		break;
2771 	case V_RDANDWR:
2772 		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) &&
2773 		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
2774 			return (V_TRUE);
2775 		break;
2776 	case V_RDORWR:
2777 		if ((atomic_add_64_nv((&(vp->v_mmap_read)), 0)) ||
2778 		    (atomic_add_64_nv((&(vp->v_mmap_write)), 0)))
2779 			return (V_TRUE);
2780 		break;
2781 	case V_READ:
2782 		if (atomic_add_64_nv((&(vp->v_mmap_read)), 0))
2783 			return (V_TRUE);
2784 		break;
2785 	}
2786 #else
2787 	switch (mode) {
2788 	case V_WRITE:
2789 		if (vp->v_mmap_write)
2790 			return (V_TRUE);
2791 		break;
2792 	case V_RDANDWR:
2793 		if (vp->v_mmap_read && vp->v_mmap_write)
2794 			return (V_TRUE);
2795 		break;
2796 	case V_RDORWR:
2797 		if (vp->v_mmap_read || vp->v_mmap_write)
2798 			return (V_TRUE);
2799 		break;
2800 	case V_READ:
2801 		if (vp->v_mmap_read)
2802 			return (V_TRUE);
2803 		break;
2804 	}
2805 #endif
2806 
2807 	return (V_FALSE);
2808 }
2809 
2810 /*
2811  * Set the operations vector for a vnode.
2812  *
2813  * FEM ensures that the v_femhead pointer is filled in before the
2814  * v_op pointer is changed.  This means that if the v_femhead pointer
2815  * is NULL, and the v_op field hasn't changed since before which checked
2816  * the v_femhead pointer; then our update is ok - we are not racing with
2817  * FEM.
2818  */
2819 void
2820 vn_setops(vnode_t *vp, vnodeops_t *vnodeops)
2821 {
2822 	vnodeops_t	*op;
2823 
2824 	ASSERT(vp != NULL);
2825 	ASSERT(vnodeops != NULL);
2826 
2827 	op = vp->v_op;
2828 	membar_consumer();
2829 	/*
2830 	 * If vp->v_femhead == NULL, then we'll call casptr() to do the
2831 	 * compare-and-swap on vp->v_op.  If either fails, then FEM is
2832 	 * in effect on the vnode and we need to have FEM deal with it.
2833 	 */
2834 	if (vp->v_femhead != NULL || casptr(&vp->v_op, op, vnodeops) != op) {
2835 		fem_setvnops(vp, vnodeops);
2836 	}
2837 }
2838 
2839 /*
2840  * Retrieve the operations vector for a vnode
2841  * As with vn_setops(above); make sure we aren't racing with FEM.
2842  * FEM sets the v_op to a special, internal, vnodeops that wouldn't
2843  * make sense to the callers of this routine.
2844  */
2845 vnodeops_t *
2846 vn_getops(vnode_t *vp)
2847 {
2848 	vnodeops_t	*op;
2849 
2850 	ASSERT(vp != NULL);
2851 
2852 	op = vp->v_op;
2853 	membar_consumer();
2854 	if (vp->v_femhead == NULL && op == vp->v_op) {
2855 		return (op);
2856 	} else {
2857 		return (fem_getvnops(vp));
2858 	}
2859 }
2860 
2861 /*
2862  * Returns non-zero (1) if the vnodeops matches that of the vnode.
2863  * Returns zero (0) if not.
2864  */
2865 int
2866 vn_matchops(vnode_t *vp, vnodeops_t *vnodeops)
2867 {
2868 	return (vn_getops(vp) == vnodeops);
2869 }
2870 
2871 /*
2872  * Returns non-zero (1) if the specified operation matches the
2873  * corresponding operation for that the vnode.
2874  * Returns zero (0) if not.
2875  */
2876 
2877 #define	MATCHNAME(n1, n2) (((n1)[0] == (n2)[0]) && (strcmp((n1), (n2)) == 0))
2878 
2879 int
2880 vn_matchopval(vnode_t *vp, char *vopname, fs_generic_func_p funcp)
2881 {
2882 	const fs_operation_trans_def_t *otdp;
2883 	fs_generic_func_p *loc = NULL;
2884 	vnodeops_t	*vop = vn_getops(vp);
2885 
2886 	ASSERT(vopname != NULL);
2887 
2888 	for (otdp = vn_ops_table; otdp->name != NULL; otdp++) {
2889 		if (MATCHNAME(otdp->name, vopname)) {
2890 			loc = (fs_generic_func_p *)
2891 			    ((char *)(vop) + otdp->offset);
2892 			break;
2893 		}
2894 	}
2895 
2896 	return ((loc != NULL) && (*loc == funcp));
2897 }
2898 
2899 /*
2900  * fs_new_caller_id() needs to return a unique ID on a given local system.
2901  * The IDs do not need to survive across reboots.  These are primarily
2902  * used so that (FEM) monitors can detect particular callers (such as
2903  * the NFS server) to a given vnode/vfs operation.
2904  */
2905 u_longlong_t
2906 fs_new_caller_id()
2907 {
2908 	static uint64_t next_caller_id = 0LL; /* First call returns 1 */
2909 
2910 	return ((u_longlong_t)atomic_add_64_nv(&next_caller_id, 1));
2911 }
2912 
2913 /*
2914  * Given a starting vnode and a path, updates the path in the target vnode in
2915  * a safe manner.  If the vnode already has path information embedded, then the
2916  * cached path is left untouched.
2917  */
2918 
2919 size_t max_vnode_path = 4 * MAXPATHLEN;
2920 
2921 void
2922 vn_setpath(vnode_t *rootvp, struct vnode *startvp, struct vnode *vp,
2923     const char *path, size_t plen)
2924 {
2925 	char	*rpath;
2926 	vnode_t	*base;
2927 	size_t	rpathlen, rpathalloc;
2928 	int	doslash = 1;
2929 
2930 	if (*path == '/') {
2931 		base = rootvp;
2932 		path++;
2933 		plen--;
2934 	} else {
2935 		base = startvp;
2936 	}
2937 
2938 	/*
2939 	 * We cannot grab base->v_lock while we hold vp->v_lock because of
2940 	 * the potential for deadlock.
2941 	 */
2942 	mutex_enter(&base->v_lock);
2943 	if (base->v_path == NULL) {
2944 		mutex_exit(&base->v_lock);
2945 		return;
2946 	}
2947 
2948 	rpathlen = strlen(base->v_path);
2949 	rpathalloc = rpathlen + plen + 1;
2950 	/* Avoid adding a slash if there's already one there */
2951 	if (base->v_path[rpathlen-1] == '/')
2952 		doslash = 0;
2953 	else
2954 		rpathalloc++;
2955 
2956 	/*
2957 	 * We don't want to call kmem_alloc(KM_SLEEP) with kernel locks held,
2958 	 * so we must do this dance.  If, by chance, something changes the path,
2959 	 * just give up since there is no real harm.
2960 	 */
2961 	mutex_exit(&base->v_lock);
2962 
2963 	/* Paths should stay within reason */
2964 	if (rpathalloc > max_vnode_path)
2965 		return;
2966 
2967 	rpath = kmem_alloc(rpathalloc, KM_SLEEP);
2968 
2969 	mutex_enter(&base->v_lock);
2970 	if (base->v_path == NULL || strlen(base->v_path) != rpathlen) {
2971 		mutex_exit(&base->v_lock);
2972 		kmem_free(rpath, rpathalloc);
2973 		return;
2974 	}
2975 	bcopy(base->v_path, rpath, rpathlen);
2976 	mutex_exit(&base->v_lock);
2977 
2978 	if (doslash)
2979 		rpath[rpathlen++] = '/';
2980 	bcopy(path, rpath + rpathlen, plen);
2981 	rpath[rpathlen + plen] = '\0';
2982 
2983 	mutex_enter(&vp->v_lock);
2984 	if (vp->v_path != NULL) {
2985 		mutex_exit(&vp->v_lock);
2986 		kmem_free(rpath, rpathalloc);
2987 	} else {
2988 		vp->v_path = rpath;
2989 		mutex_exit(&vp->v_lock);
2990 	}
2991 }
2992 
2993 /*
2994  * Sets the path to the vnode to be the given string, regardless of current
2995  * context.  The string must be a complete path from rootdir.  This is only used
2996  * by fsop_root() for setting the path based on the mountpoint.
2997  */
2998 void
2999 vn_setpath_str(struct vnode *vp, const char *str, size_t len)
3000 {
3001 	char *buf = kmem_alloc(len + 1, KM_SLEEP);
3002 
3003 	mutex_enter(&vp->v_lock);
3004 	if (vp->v_path != NULL) {
3005 		mutex_exit(&vp->v_lock);
3006 		kmem_free(buf, len + 1);
3007 		return;
3008 	}
3009 
3010 	vp->v_path = buf;
3011 	bcopy(str, vp->v_path, len);
3012 	vp->v_path[len] = '\0';
3013 
3014 	mutex_exit(&vp->v_lock);
3015 }
3016 
3017 /*
3018  * Called from within filesystem's vop_rename() to handle renames once the
3019  * target vnode is available.
3020  */
3021 void
3022 vn_renamepath(vnode_t *dvp, vnode_t *vp, const char *nm, size_t len)
3023 {
3024 	char *tmp;
3025 
3026 	mutex_enter(&vp->v_lock);
3027 	tmp = vp->v_path;
3028 	vp->v_path = NULL;
3029 	mutex_exit(&vp->v_lock);
3030 	vn_setpath(rootdir, dvp, vp, nm, len);
3031 	if (tmp != NULL)
3032 		kmem_free(tmp, strlen(tmp) + 1);
3033 }
3034 
3035 /*
3036  * Similar to vn_setpath_str(), this function sets the path of the destination
3037  * vnode to the be the same as the source vnode.
3038  */
3039 void
3040 vn_copypath(struct vnode *src, struct vnode *dst)
3041 {
3042 	char *buf;
3043 	int alloc;
3044 
3045 	mutex_enter(&src->v_lock);
3046 	if (src->v_path == NULL) {
3047 		mutex_exit(&src->v_lock);
3048 		return;
3049 	}
3050 	alloc = strlen(src->v_path) + 1;
3051 
3052 	/* avoid kmem_alloc() with lock held */
3053 	mutex_exit(&src->v_lock);
3054 	buf = kmem_alloc(alloc, KM_SLEEP);
3055 	mutex_enter(&src->v_lock);
3056 	if (src->v_path == NULL || strlen(src->v_path) + 1 != alloc) {
3057 		mutex_exit(&src->v_lock);
3058 		kmem_free(buf, alloc);
3059 		return;
3060 	}
3061 	bcopy(src->v_path, buf, alloc);
3062 	mutex_exit(&src->v_lock);
3063 
3064 	mutex_enter(&dst->v_lock);
3065 	if (dst->v_path != NULL) {
3066 		mutex_exit(&dst->v_lock);
3067 		kmem_free(buf, alloc);
3068 		return;
3069 	}
3070 	dst->v_path = buf;
3071 	mutex_exit(&dst->v_lock);
3072 }
3073 
3074 /*
3075  * XXX Private interface for segvn routines that handle vnode
3076  * large page segments.
3077  *
3078  * return 1 if vp's file system VOP_PAGEIO() implementation
3079  * can be safely used instead of VOP_GETPAGE() for handling
3080  * pagefaults against regular non swap files. VOP_PAGEIO()
3081  * interface is considered safe here if its implementation
3082  * is very close to VOP_GETPAGE() implementation.
3083  * e.g. It zero's out the part of the page beyond EOF. Doesn't
3084  * panic if there're file holes but instead returns an error.
3085  * Doesn't assume file won't be changed by user writes, etc.
3086  *
3087  * return 0 otherwise.
3088  *
3089  * For now allow segvn to only use VOP_PAGEIO() with ufs and nfs.
3090  */
3091 int
3092 vn_vmpss_usepageio(vnode_t *vp)
3093 {
3094 	vfs_t   *vfsp = vp->v_vfsp;
3095 	char *fsname = vfssw[vfsp->vfs_fstype].vsw_name;
3096 	char *pageio_ok_fss[] = {"ufs", "nfs", NULL};
3097 	char **fsok = pageio_ok_fss;
3098 
3099 	if (fsname == NULL) {
3100 		return (0);
3101 	}
3102 
3103 	for (; *fsok; fsok++) {
3104 		if (strcmp(*fsok, fsname) == 0) {
3105 			return (1);
3106 		}
3107 	}
3108 	return (0);
3109 }
3110 
3111 /* VOP_XXX() macros call the corresponding fop_xxx() function */
3112 
3113 int
3114 fop_open(
3115 	vnode_t **vpp,
3116 	int mode,
3117 	cred_t *cr,
3118 	caller_context_t *ct)
3119 {
3120 	int ret;
3121 	vnode_t *vp = *vpp;
3122 
3123 	VN_HOLD(vp);
3124 	/*
3125 	 * Adding to the vnode counts before calling open
3126 	 * avoids the need for a mutex. It circumvents a race
3127 	 * condition where a query made on the vnode counts results in a
3128 	 * false negative. The inquirer goes away believing the file is
3129 	 * not open when there is an open on the file already under way.
3130 	 *
3131 	 * The counts are meant to prevent NFS from granting a delegation
3132 	 * when it would be dangerous to do so.
3133 	 *
3134 	 * The vnode counts are only kept on regular files
3135 	 */
3136 	if ((*vpp)->v_type == VREG) {
3137 		if (mode & FREAD)
3138 			atomic_add_32(&((*vpp)->v_rdcnt), 1);
3139 		if (mode & FWRITE)
3140 			atomic_add_32(&((*vpp)->v_wrcnt), 1);
3141 	}
3142 
3143 	VOPXID_MAP_CR(vp, cr);
3144 
3145 	ret = (*(*(vpp))->v_op->vop_open)(vpp, mode, cr, ct);
3146 
3147 	if (ret) {
3148 		/*
3149 		 * Use the saved vp just in case the vnode ptr got trashed
3150 		 * by the error.
3151 		 */
3152 		VOPSTATS_UPDATE(vp, open);
3153 		if ((vp->v_type == VREG) && (mode & FREAD))
3154 			atomic_add_32(&(vp->v_rdcnt), -1);
3155 		if ((vp->v_type == VREG) && (mode & FWRITE))
3156 			atomic_add_32(&(vp->v_wrcnt), -1);
3157 	} else {
3158 		/*
3159 		 * Some filesystems will return a different vnode,
3160 		 * but the same path was still used to open it.
3161 		 * So if we do change the vnode and need to
3162 		 * copy over the path, do so here, rather than special
3163 		 * casing each filesystem. Adjust the vnode counts to
3164 		 * reflect the vnode switch.
3165 		 */
3166 		VOPSTATS_UPDATE(*vpp, open);
3167 		if (*vpp != vp && *vpp != NULL) {
3168 			vn_copypath(vp, *vpp);
3169 			if (((*vpp)->v_type == VREG) && (mode & FREAD))
3170 				atomic_add_32(&((*vpp)->v_rdcnt), 1);
3171 			if ((vp->v_type == VREG) && (mode & FREAD))
3172 				atomic_add_32(&(vp->v_rdcnt), -1);
3173 			if (((*vpp)->v_type == VREG) && (mode & FWRITE))
3174 				atomic_add_32(&((*vpp)->v_wrcnt), 1);
3175 			if ((vp->v_type == VREG) && (mode & FWRITE))
3176 				atomic_add_32(&(vp->v_wrcnt), -1);
3177 		}
3178 	}
3179 	VN_RELE(vp);
3180 	return (ret);
3181 }
3182 
3183 int
3184 fop_close(
3185 	vnode_t *vp,
3186 	int flag,
3187 	int count,
3188 	offset_t offset,
3189 	cred_t *cr,
3190 	caller_context_t *ct)
3191 {
3192 	int err;
3193 
3194 	VOPXID_MAP_CR(vp, cr);
3195 
3196 	err = (*(vp)->v_op->vop_close)(vp, flag, count, offset, cr, ct);
3197 	VOPSTATS_UPDATE(vp, close);
3198 	/*
3199 	 * Check passed in count to handle possible dups. Vnode counts are only
3200 	 * kept on regular files
3201 	 */
3202 	if ((vp->v_type == VREG) && (count == 1))  {
3203 		if (flag & FREAD) {
3204 			ASSERT(vp->v_rdcnt > 0);
3205 			atomic_add_32(&(vp->v_rdcnt), -1);
3206 		}
3207 		if (flag & FWRITE) {
3208 			ASSERT(vp->v_wrcnt > 0);
3209 			atomic_add_32(&(vp->v_wrcnt), -1);
3210 		}
3211 	}
3212 	return (err);
3213 }
3214 
3215 int
3216 fop_read(
3217 	vnode_t *vp,
3218 	uio_t *uiop,
3219 	int ioflag,
3220 	cred_t *cr,
3221 	caller_context_t *ct)
3222 {
3223 	int	err;
3224 	ssize_t	resid_start = uiop->uio_resid;
3225 
3226 	VOPXID_MAP_CR(vp, cr);
3227 
3228 	err = (*(vp)->v_op->vop_read)(vp, uiop, ioflag, cr, ct);
3229 	VOPSTATS_UPDATE_IO(vp, read,
3230 	    read_bytes, (resid_start - uiop->uio_resid));
3231 	return (err);
3232 }
3233 
3234 int
3235 fop_write(
3236 	vnode_t *vp,
3237 	uio_t *uiop,
3238 	int ioflag,
3239 	cred_t *cr,
3240 	caller_context_t *ct)
3241 {
3242 	int	err;
3243 	ssize_t	resid_start = uiop->uio_resid;
3244 
3245 	VOPXID_MAP_CR(vp, cr);
3246 
3247 	err = (*(vp)->v_op->vop_write)(vp, uiop, ioflag, cr, ct);
3248 	VOPSTATS_UPDATE_IO(vp, write,
3249 	    write_bytes, (resid_start - uiop->uio_resid));
3250 	return (err);
3251 }
3252 
3253 int
3254 fop_ioctl(
3255 	vnode_t *vp,
3256 	int cmd,
3257 	intptr_t arg,
3258 	int flag,
3259 	cred_t *cr,
3260 	int *rvalp,
3261 	caller_context_t *ct)
3262 {
3263 	int	err;
3264 
3265 	VOPXID_MAP_CR(vp, cr);
3266 
3267 	err = (*(vp)->v_op->vop_ioctl)(vp, cmd, arg, flag, cr, rvalp, ct);
3268 	VOPSTATS_UPDATE(vp, ioctl);
3269 	return (err);
3270 }
3271 
3272 int
3273 fop_setfl(
3274 	vnode_t *vp,
3275 	int oflags,
3276 	int nflags,
3277 	cred_t *cr,
3278 	caller_context_t *ct)
3279 {
3280 	int	err;
3281 
3282 	VOPXID_MAP_CR(vp, cr);
3283 
3284 	err = (*(vp)->v_op->vop_setfl)(vp, oflags, nflags, cr, ct);
3285 	VOPSTATS_UPDATE(vp, setfl);
3286 	return (err);
3287 }
3288 
3289 int
3290 fop_getattr(
3291 	vnode_t *vp,
3292 	vattr_t *vap,
3293 	int flags,
3294 	cred_t *cr,
3295 	caller_context_t *ct)
3296 {
3297 	int	err;
3298 
3299 	VOPXID_MAP_CR(vp, cr);
3300 
3301 	/*
3302 	 * If this file system doesn't understand the xvattr extensions
3303 	 * then turn off the xvattr bit.
3304 	 */
3305 	if (vfs_has_feature(vp->v_vfsp, VFSFT_XVATTR) == 0) {
3306 		vap->va_mask &= ~AT_XVATTR;
3307 	}
3308 
3309 	/*
3310 	 * We're only allowed to skip the ACL check iff we used a 32 bit
3311 	 * ACE mask with VOP_ACCESS() to determine permissions.
3312 	 */
3313 	if ((flags & ATTR_NOACLCHECK) &&
3314 	    vfs_has_feature(vp->v_vfsp, VFSFT_ACEMASKONACCESS) == 0) {
3315 		return (EINVAL);
3316 	}
3317 	err = (*(vp)->v_op->vop_getattr)(vp, vap, flags, cr, ct);
3318 	VOPSTATS_UPDATE(vp, getattr);
3319 	return (err);
3320 }
3321 
3322 int
3323 fop_setattr(
3324 	vnode_t *vp,
3325 	vattr_t *vap,
3326 	int flags,
3327 	cred_t *cr,
3328 	caller_context_t *ct)
3329 {
3330 	int	err;
3331 
3332 	VOPXID_MAP_CR(vp, cr);
3333 
3334 	/*
3335 	 * If this file system doesn't understand the xvattr extensions
3336 	 * then turn off the xvattr bit.
3337 	 */
3338 	if (vfs_has_feature(vp->v_vfsp, VFSFT_XVATTR) == 0) {
3339 		vap->va_mask &= ~AT_XVATTR;
3340 	}
3341 
3342 	/*
3343 	 * We're only allowed to skip the ACL check iff we used a 32 bit
3344 	 * ACE mask with VOP_ACCESS() to determine permissions.
3345 	 */
3346 	if ((flags & ATTR_NOACLCHECK) &&
3347 	    vfs_has_feature(vp->v_vfsp, VFSFT_ACEMASKONACCESS) == 0) {
3348 		return (EINVAL);
3349 	}
3350 	err = (*(vp)->v_op->vop_setattr)(vp, vap, flags, cr, ct);
3351 	VOPSTATS_UPDATE(vp, setattr);
3352 	return (err);
3353 }
3354 
3355 int
3356 fop_access(
3357 	vnode_t *vp,
3358 	int mode,
3359 	int flags,
3360 	cred_t *cr,
3361 	caller_context_t *ct)
3362 {
3363 	int	err;
3364 
3365 	if ((flags & V_ACE_MASK) &&
3366 	    vfs_has_feature(vp->v_vfsp, VFSFT_ACEMASKONACCESS) == 0) {
3367 		return (EINVAL);
3368 	}
3369 
3370 	VOPXID_MAP_CR(vp, cr);
3371 
3372 	err = (*(vp)->v_op->vop_access)(vp, mode, flags, cr, ct);
3373 	VOPSTATS_UPDATE(vp, access);
3374 	return (err);
3375 }
3376 
3377 int
3378 fop_lookup(
3379 	vnode_t *dvp,
3380 	char *nm,
3381 	vnode_t **vpp,
3382 	pathname_t *pnp,
3383 	int flags,
3384 	vnode_t *rdir,
3385 	cred_t *cr,
3386 	caller_context_t *ct,
3387 	int *deflags,		/* Returned per-dirent flags */
3388 	pathname_t *ppnp)	/* Returned case-preserved name in directory */
3389 {
3390 	int ret;
3391 
3392 	/*
3393 	 * If this file system doesn't support case-insensitive access
3394 	 * and said access is requested, fail quickly.  It is required
3395 	 * that if the vfs supports case-insensitive lookup, it also
3396 	 * supports extended dirent flags.
3397 	 */
3398 	if (flags & FIGNORECASE &&
3399 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3400 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3401 		return (EINVAL);
3402 
3403 	VOPXID_MAP_CR(dvp, cr);
3404 
3405 	if ((flags & LOOKUP_XATTR) && (flags & LOOKUP_HAVE_SYSATTR_DIR) == 0) {
3406 		ret = xattr_dir_lookup(dvp, vpp, flags, cr);
3407 	} else {
3408 		ret = (*(dvp)->v_op->vop_lookup)
3409 		    (dvp, nm, vpp, pnp, flags, rdir, cr, ct, deflags, ppnp);
3410 	}
3411 	if (ret == 0 && *vpp) {
3412 		VOPSTATS_UPDATE(*vpp, lookup);
3413 		if ((*vpp)->v_path == NULL) {
3414 			vn_setpath(rootdir, dvp, *vpp, nm, strlen(nm));
3415 		}
3416 	}
3417 
3418 	return (ret);
3419 }
3420 
3421 int
3422 fop_create(
3423 	vnode_t *dvp,
3424 	char *name,
3425 	vattr_t *vap,
3426 	vcexcl_t excl,
3427 	int mode,
3428 	vnode_t **vpp,
3429 	cred_t *cr,
3430 	int flags,
3431 	caller_context_t *ct,
3432 	vsecattr_t *vsecp)	/* ACL to set during create */
3433 {
3434 	int ret;
3435 
3436 	if (vsecp != NULL &&
3437 	    vfs_has_feature(dvp->v_vfsp, VFSFT_ACLONCREATE) == 0) {
3438 		return (EINVAL);
3439 	}
3440 	/*
3441 	 * If this file system doesn't support case-insensitive access
3442 	 * and said access is requested, fail quickly.
3443 	 */
3444 	if (flags & FIGNORECASE &&
3445 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3446 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3447 		return (EINVAL);
3448 
3449 	VOPXID_MAP_CR(dvp, cr);
3450 
3451 	ret = (*(dvp)->v_op->vop_create)
3452 	    (dvp, name, vap, excl, mode, vpp, cr, flags, ct, vsecp);
3453 	if (ret == 0 && *vpp) {
3454 		VOPSTATS_UPDATE(*vpp, create);
3455 		if ((*vpp)->v_path == NULL) {
3456 			vn_setpath(rootdir, dvp, *vpp, name, strlen(name));
3457 		}
3458 	}
3459 
3460 	return (ret);
3461 }
3462 
3463 int
3464 fop_remove(
3465 	vnode_t *dvp,
3466 	char *nm,
3467 	cred_t *cr,
3468 	caller_context_t *ct,
3469 	int flags)
3470 {
3471 	int	err;
3472 
3473 	/*
3474 	 * If this file system doesn't support case-insensitive access
3475 	 * and said access is requested, fail quickly.
3476 	 */
3477 	if (flags & FIGNORECASE &&
3478 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3479 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3480 		return (EINVAL);
3481 
3482 	VOPXID_MAP_CR(dvp, cr);
3483 
3484 	err = (*(dvp)->v_op->vop_remove)(dvp, nm, cr, ct, flags);
3485 	VOPSTATS_UPDATE(dvp, remove);
3486 	return (err);
3487 }
3488 
3489 int
3490 fop_link(
3491 	vnode_t *tdvp,
3492 	vnode_t *svp,
3493 	char *tnm,
3494 	cred_t *cr,
3495 	caller_context_t *ct,
3496 	int flags)
3497 {
3498 	int	err;
3499 
3500 	/*
3501 	 * If the target file system doesn't support case-insensitive access
3502 	 * and said access is requested, fail quickly.
3503 	 */
3504 	if (flags & FIGNORECASE &&
3505 	    (vfs_has_feature(tdvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3506 	    vfs_has_feature(tdvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3507 		return (EINVAL);
3508 
3509 	VOPXID_MAP_CR(tdvp, cr);
3510 
3511 	err = (*(tdvp)->v_op->vop_link)(tdvp, svp, tnm, cr, ct, flags);
3512 	VOPSTATS_UPDATE(tdvp, link);
3513 	return (err);
3514 }
3515 
3516 int
3517 fop_rename(
3518 	vnode_t *sdvp,
3519 	char *snm,
3520 	vnode_t *tdvp,
3521 	char *tnm,
3522 	cred_t *cr,
3523 	caller_context_t *ct,
3524 	int flags)
3525 {
3526 	int	err;
3527 
3528 	/*
3529 	 * If the file system involved does not support
3530 	 * case-insensitive access and said access is requested, fail
3531 	 * quickly.
3532 	 */
3533 	if (flags & FIGNORECASE &&
3534 	    ((vfs_has_feature(sdvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3535 	    vfs_has_feature(sdvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0)))
3536 		return (EINVAL);
3537 
3538 	VOPXID_MAP_CR(tdvp, cr);
3539 
3540 	err = (*(sdvp)->v_op->vop_rename)(sdvp, snm, tdvp, tnm, cr, ct, flags);
3541 	VOPSTATS_UPDATE(sdvp, rename);
3542 	return (err);
3543 }
3544 
3545 int
3546 fop_mkdir(
3547 	vnode_t *dvp,
3548 	char *dirname,
3549 	vattr_t *vap,
3550 	vnode_t **vpp,
3551 	cred_t *cr,
3552 	caller_context_t *ct,
3553 	int flags,
3554 	vsecattr_t *vsecp)	/* ACL to set during create */
3555 {
3556 	int ret;
3557 
3558 	if (vsecp != NULL &&
3559 	    vfs_has_feature(dvp->v_vfsp, VFSFT_ACLONCREATE) == 0) {
3560 		return (EINVAL);
3561 	}
3562 	/*
3563 	 * If this file system doesn't support case-insensitive access
3564 	 * and said access is requested, fail quickly.
3565 	 */
3566 	if (flags & FIGNORECASE &&
3567 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3568 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3569 		return (EINVAL);
3570 
3571 	VOPXID_MAP_CR(dvp, cr);
3572 
3573 	ret = (*(dvp)->v_op->vop_mkdir)
3574 	    (dvp, dirname, vap, vpp, cr, ct, flags, vsecp);
3575 	if (ret == 0 && *vpp) {
3576 		VOPSTATS_UPDATE(*vpp, mkdir);
3577 		if ((*vpp)->v_path == NULL) {
3578 			vn_setpath(rootdir, dvp, *vpp, dirname,
3579 			    strlen(dirname));
3580 		}
3581 	}
3582 
3583 	return (ret);
3584 }
3585 
3586 int
3587 fop_rmdir(
3588 	vnode_t *dvp,
3589 	char *nm,
3590 	vnode_t *cdir,
3591 	cred_t *cr,
3592 	caller_context_t *ct,
3593 	int flags)
3594 {
3595 	int	err;
3596 
3597 	/*
3598 	 * If this file system doesn't support case-insensitive access
3599 	 * and said access is requested, fail quickly.
3600 	 */
3601 	if (flags & FIGNORECASE &&
3602 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3603 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3604 		return (EINVAL);
3605 
3606 	VOPXID_MAP_CR(dvp, cr);
3607 
3608 	err = (*(dvp)->v_op->vop_rmdir)(dvp, nm, cdir, cr, ct, flags);
3609 	VOPSTATS_UPDATE(dvp, rmdir);
3610 	return (err);
3611 }
3612 
3613 int
3614 fop_readdir(
3615 	vnode_t *vp,
3616 	uio_t *uiop,
3617 	cred_t *cr,
3618 	int *eofp,
3619 	caller_context_t *ct,
3620 	int flags)
3621 {
3622 	int	err;
3623 	ssize_t	resid_start = uiop->uio_resid;
3624 
3625 	/*
3626 	 * If this file system doesn't support retrieving directory
3627 	 * entry flags and said access is requested, fail quickly.
3628 	 */
3629 	if (flags & V_RDDIR_ENTFLAGS &&
3630 	    vfs_has_feature(vp->v_vfsp, VFSFT_DIRENTFLAGS) == 0)
3631 		return (EINVAL);
3632 
3633 	VOPXID_MAP_CR(vp, cr);
3634 
3635 	err = (*(vp)->v_op->vop_readdir)(vp, uiop, cr, eofp, ct, flags);
3636 	VOPSTATS_UPDATE_IO(vp, readdir,
3637 	    readdir_bytes, (resid_start - uiop->uio_resid));
3638 	return (err);
3639 }
3640 
3641 int
3642 fop_symlink(
3643 	vnode_t *dvp,
3644 	char *linkname,
3645 	vattr_t *vap,
3646 	char *target,
3647 	cred_t *cr,
3648 	caller_context_t *ct,
3649 	int flags)
3650 {
3651 	int	err;
3652 	xvattr_t xvattr;
3653 
3654 	/*
3655 	 * If this file system doesn't support case-insensitive access
3656 	 * and said access is requested, fail quickly.
3657 	 */
3658 	if (flags & FIGNORECASE &&
3659 	    (vfs_has_feature(dvp->v_vfsp, VFSFT_CASEINSENSITIVE) == 0 &&
3660 	    vfs_has_feature(dvp->v_vfsp, VFSFT_NOCASESENSITIVE) == 0))
3661 		return (EINVAL);
3662 
3663 	VOPXID_MAP_CR(dvp, cr);
3664 
3665 	/* check for reparse point */
3666 	if ((vfs_has_feature(dvp->v_vfsp, VFSFT_REPARSE)) &&
3667 	    (strncmp(target, FS_REPARSE_TAG_STR,
3668 	    strlen(FS_REPARSE_TAG_STR)) == 0)) {
3669 		if (!fs_reparse_mark(target, vap, &xvattr))
3670 			vap = (vattr_t *)&xvattr;
3671 	}
3672 
3673 	err = (*(dvp)->v_op->vop_symlink)
3674 	    (dvp, linkname, vap, target, cr, ct, flags);
3675 	VOPSTATS_UPDATE(dvp, symlink);
3676 	return (err);
3677 }
3678 
3679 int
3680 fop_readlink(
3681 	vnode_t *vp,
3682 	uio_t *uiop,
3683 	cred_t *cr,
3684 	caller_context_t *ct)
3685 {
3686 	int	err;
3687 
3688 	VOPXID_MAP_CR(vp, cr);
3689 
3690 	err = (*(vp)->v_op->vop_readlink)(vp, uiop, cr, ct);
3691 	VOPSTATS_UPDATE(vp, readlink);
3692 	return (err);
3693 }
3694 
3695 int
3696 fop_fsync(
3697 	vnode_t *vp,
3698 	int syncflag,
3699 	cred_t *cr,
3700 	caller_context_t *ct)
3701 {
3702 	int	err;
3703 
3704 	VOPXID_MAP_CR(vp, cr);
3705 
3706 	err = (*(vp)->v_op->vop_fsync)(vp, syncflag, cr, ct);
3707 	VOPSTATS_UPDATE(vp, fsync);
3708 	return (err);
3709 }
3710 
3711 void
3712 fop_inactive(
3713 	vnode_t *vp,
3714 	cred_t *cr,
3715 	caller_context_t *ct)
3716 {
3717 	/* Need to update stats before vop call since we may lose the vnode */
3718 	VOPSTATS_UPDATE(vp, inactive);
3719 
3720 	VOPXID_MAP_CR(vp, cr);
3721 
3722 	(*(vp)->v_op->vop_inactive)(vp, cr, ct);
3723 }
3724 
3725 int
3726 fop_fid(
3727 	vnode_t *vp,
3728 	fid_t *fidp,
3729 	caller_context_t *ct)
3730 {
3731 	int	err;
3732 
3733 	err = (*(vp)->v_op->vop_fid)(vp, fidp, ct);
3734 	VOPSTATS_UPDATE(vp, fid);
3735 	return (err);
3736 }
3737 
3738 int
3739 fop_rwlock(
3740 	vnode_t *vp,
3741 	int write_lock,
3742 	caller_context_t *ct)
3743 {
3744 	int	ret;
3745 
3746 	ret = ((*(vp)->v_op->vop_rwlock)(vp, write_lock, ct));
3747 	VOPSTATS_UPDATE(vp, rwlock);
3748 	return (ret);
3749 }
3750 
3751 void
3752 fop_rwunlock(
3753 	vnode_t *vp,
3754 	int write_lock,
3755 	caller_context_t *ct)
3756 {
3757 	(*(vp)->v_op->vop_rwunlock)(vp, write_lock, ct);
3758 	VOPSTATS_UPDATE(vp, rwunlock);
3759 }
3760 
3761 int
3762 fop_seek(
3763 	vnode_t *vp,
3764 	offset_t ooff,
3765 	offset_t *noffp,
3766 	caller_context_t *ct)
3767 {
3768 	int	err;
3769 
3770 	err = (*(vp)->v_op->vop_seek)(vp, ooff, noffp, ct);
3771 	VOPSTATS_UPDATE(vp, seek);
3772 	return (err);
3773 }
3774 
3775 int
3776 fop_cmp(
3777 	vnode_t *vp1,
3778 	vnode_t *vp2,
3779 	caller_context_t *ct)
3780 {
3781 	int	err;
3782 
3783 	err = (*(vp1)->v_op->vop_cmp)(vp1, vp2, ct);
3784 	VOPSTATS_UPDATE(vp1, cmp);
3785 	return (err);
3786 }
3787 
3788 int
3789 fop_frlock(
3790 	vnode_t *vp,
3791 	int cmd,
3792 	flock64_t *bfp,
3793 	int flag,
3794 	offset_t offset,
3795 	struct flk_callback *flk_cbp,
3796 	cred_t *cr,
3797 	caller_context_t *ct)
3798 {
3799 	int	err;
3800 
3801 	VOPXID_MAP_CR(vp, cr);
3802 
3803 	err = (*(vp)->v_op->vop_frlock)
3804 	    (vp, cmd, bfp, flag, offset, flk_cbp, cr, ct);
3805 	VOPSTATS_UPDATE(vp, frlock);
3806 	return (err);
3807 }
3808 
3809 int
3810 fop_space(
3811 	vnode_t *vp,
3812 	int cmd,
3813 	flock64_t *bfp,
3814 	int flag,
3815 	offset_t offset,
3816 	cred_t *cr,
3817 	caller_context_t *ct)
3818 {
3819 	int	err;
3820 
3821 	VOPXID_MAP_CR(vp, cr);
3822 
3823 	err = (*(vp)->v_op->vop_space)(vp, cmd, bfp, flag, offset, cr, ct);
3824 	VOPSTATS_UPDATE(vp, space);
3825 	return (err);
3826 }
3827 
3828 int
3829 fop_realvp(
3830 	vnode_t *vp,
3831 	vnode_t **vpp,
3832 	caller_context_t *ct)
3833 {
3834 	int	err;
3835 
3836 	err = (*(vp)->v_op->vop_realvp)(vp, vpp, ct);
3837 	VOPSTATS_UPDATE(vp, realvp);
3838 	return (err);
3839 }
3840 
3841 int
3842 fop_getpage(
3843 	vnode_t *vp,
3844 	offset_t off,
3845 	size_t len,
3846 	uint_t *protp,
3847 	page_t **plarr,
3848 	size_t plsz,
3849 	struct seg *seg,
3850 	caddr_t addr,
3851 	enum seg_rw rw,
3852 	cred_t *cr,
3853 	caller_context_t *ct)
3854 {
3855 	int	err;
3856 
3857 	VOPXID_MAP_CR(vp, cr);
3858 
3859 	err = (*(vp)->v_op->vop_getpage)
3860 	    (vp, off, len, protp, plarr, plsz, seg, addr, rw, cr, ct);
3861 	VOPSTATS_UPDATE(vp, getpage);
3862 	return (err);
3863 }
3864 
3865 int
3866 fop_putpage(
3867 	vnode_t *vp,
3868 	offset_t off,
3869 	size_t len,
3870 	int flags,
3871 	cred_t *cr,
3872 	caller_context_t *ct)
3873 {
3874 	int	err;
3875 
3876 	VOPXID_MAP_CR(vp, cr);
3877 
3878 	err = (*(vp)->v_op->vop_putpage)(vp, off, len, flags, cr, ct);
3879 	VOPSTATS_UPDATE(vp, putpage);
3880 	return (err);
3881 }
3882 
3883 int
3884 fop_map(
3885 	vnode_t *vp,
3886 	offset_t off,
3887 	struct as *as,
3888 	caddr_t *addrp,
3889 	size_t len,
3890 	uchar_t prot,
3891 	uchar_t maxprot,
3892 	uint_t flags,
3893 	cred_t *cr,
3894 	caller_context_t *ct)
3895 {
3896 	int	err;
3897 
3898 	VOPXID_MAP_CR(vp, cr);
3899 
3900 	err = (*(vp)->v_op->vop_map)
3901 	    (vp, off, as, addrp, len, prot, maxprot, flags, cr, ct);
3902 	VOPSTATS_UPDATE(vp, map);
3903 	return (err);
3904 }
3905 
3906 int
3907 fop_addmap(
3908 	vnode_t *vp,
3909 	offset_t off,
3910 	struct as *as,
3911 	caddr_t addr,
3912 	size_t len,
3913 	uchar_t prot,
3914 	uchar_t maxprot,
3915 	uint_t flags,
3916 	cred_t *cr,
3917 	caller_context_t *ct)
3918 {
3919 	int error;
3920 	u_longlong_t delta;
3921 
3922 	VOPXID_MAP_CR(vp, cr);
3923 
3924 	error = (*(vp)->v_op->vop_addmap)
3925 	    (vp, off, as, addr, len, prot, maxprot, flags, cr, ct);
3926 
3927 	if ((!error) && (vp->v_type == VREG)) {
3928 		delta = (u_longlong_t)btopr(len);
3929 		/*
3930 		 * If file is declared MAP_PRIVATE, it can't be written back
3931 		 * even if open for write. Handle as read.
3932 		 */
3933 		if (flags & MAP_PRIVATE) {
3934 			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3935 			    (int64_t)delta);
3936 		} else {
3937 			/*
3938 			 * atomic_add_64 forces the fetch of a 64 bit value to
3939 			 * be atomic on 32 bit machines
3940 			 */
3941 			if (maxprot & PROT_WRITE)
3942 				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
3943 				    (int64_t)delta);
3944 			if (maxprot & PROT_READ)
3945 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3946 				    (int64_t)delta);
3947 			if (maxprot & PROT_EXEC)
3948 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3949 				    (int64_t)delta);
3950 		}
3951 	}
3952 	VOPSTATS_UPDATE(vp, addmap);
3953 	return (error);
3954 }
3955 
3956 int
3957 fop_delmap(
3958 	vnode_t *vp,
3959 	offset_t off,
3960 	struct as *as,
3961 	caddr_t addr,
3962 	size_t len,
3963 	uint_t prot,
3964 	uint_t maxprot,
3965 	uint_t flags,
3966 	cred_t *cr,
3967 	caller_context_t *ct)
3968 {
3969 	int error;
3970 	u_longlong_t delta;
3971 
3972 	VOPXID_MAP_CR(vp, cr);
3973 
3974 	error = (*(vp)->v_op->vop_delmap)
3975 	    (vp, off, as, addr, len, prot, maxprot, flags, cr, ct);
3976 
3977 	/*
3978 	 * NFS calls into delmap twice, the first time
3979 	 * it simply establishes a callback mechanism and returns EAGAIN
3980 	 * while the real work is being done upon the second invocation.
3981 	 * We have to detect this here and only decrement the counts upon
3982 	 * the second delmap request.
3983 	 */
3984 	if ((error != EAGAIN) && (vp->v_type == VREG)) {
3985 
3986 		delta = (u_longlong_t)btopr(len);
3987 
3988 		if (flags & MAP_PRIVATE) {
3989 			atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
3990 			    (int64_t)(-delta));
3991 		} else {
3992 			/*
3993 			 * atomic_add_64 forces the fetch of a 64 bit value
3994 			 * to be atomic on 32 bit machines
3995 			 */
3996 			if (maxprot & PROT_WRITE)
3997 				atomic_add_64((uint64_t *)(&(vp->v_mmap_write)),
3998 				    (int64_t)(-delta));
3999 			if (maxprot & PROT_READ)
4000 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
4001 				    (int64_t)(-delta));
4002 			if (maxprot & PROT_EXEC)
4003 				atomic_add_64((uint64_t *)(&(vp->v_mmap_read)),
4004 				    (int64_t)(-delta));
4005 		}
4006 	}
4007 	VOPSTATS_UPDATE(vp, delmap);
4008 	return (error);
4009 }
4010 
4011 
4012 int
4013 fop_poll(
4014 	vnode_t *vp,
4015 	short events,
4016 	int anyyet,
4017 	short *reventsp,
4018 	struct pollhead **phpp,
4019 	caller_context_t *ct)
4020 {
4021 	int	err;
4022 
4023 	err = (*(vp)->v_op->vop_poll)(vp, events, anyyet, reventsp, phpp, ct);
4024 	VOPSTATS_UPDATE(vp, poll);
4025 	return (err);
4026 }
4027 
4028 int
4029 fop_dump(
4030 	vnode_t *vp,
4031 	caddr_t addr,
4032 	offset_t lbdn,
4033 	offset_t dblks,
4034 	caller_context_t *ct)
4035 {
4036 	int	err;
4037 
4038 	/* ensure lbdn and dblks can be passed safely to bdev_dump */
4039 	if ((lbdn != (daddr_t)lbdn) || (dblks != (int)dblks))
4040 		return (EIO);
4041 
4042 	err = (*(vp)->v_op->vop_dump)(vp, addr, lbdn, dblks, ct);
4043 	VOPSTATS_UPDATE(vp, dump);
4044 	return (err);
4045 }
4046 
4047 int
4048 fop_pathconf(
4049 	vnode_t *vp,
4050 	int cmd,
4051 	ulong_t *valp,
4052 	cred_t *cr,
4053 	caller_context_t *ct)
4054 {
4055 	int	err;
4056 
4057 	VOPXID_MAP_CR(vp, cr);
4058 
4059 	err = (*(vp)->v_op->vop_pathconf)(vp, cmd, valp, cr, ct);
4060 	VOPSTATS_UPDATE(vp, pathconf);
4061 	return (err);
4062 }
4063 
4064 int
4065 fop_pageio(
4066 	vnode_t *vp,
4067 	struct page *pp,
4068 	u_offset_t io_off,
4069 	size_t io_len,
4070 	int flags,
4071 	cred_t *cr,
4072 	caller_context_t *ct)
4073 {
4074 	int	err;
4075 
4076 	VOPXID_MAP_CR(vp, cr);
4077 
4078 	err = (*(vp)->v_op->vop_pageio)(vp, pp, io_off, io_len, flags, cr, ct);
4079 	VOPSTATS_UPDATE(vp, pageio);
4080 	return (err);
4081 }
4082 
4083 int
4084 fop_dumpctl(
4085 	vnode_t *vp,
4086 	int action,
4087 	offset_t *blkp,
4088 	caller_context_t *ct)
4089 {
4090 	int	err;
4091 	err = (*(vp)->v_op->vop_dumpctl)(vp, action, blkp, ct);
4092 	VOPSTATS_UPDATE(vp, dumpctl);
4093 	return (err);
4094 }
4095 
4096 void
4097 fop_dispose(
4098 	vnode_t *vp,
4099 	page_t *pp,
4100 	int flag,
4101 	int dn,
4102 	cred_t *cr,
4103 	caller_context_t *ct)
4104 {
4105 	/* Must do stats first since it's possible to lose the vnode */
4106 	VOPSTATS_UPDATE(vp, dispose);
4107 
4108 	VOPXID_MAP_CR(vp, cr);
4109 
4110 	(*(vp)->v_op->vop_dispose)(vp, pp, flag, dn, cr, ct);
4111 }
4112 
4113 int
4114 fop_setsecattr(
4115 	vnode_t *vp,
4116 	vsecattr_t *vsap,
4117 	int flag,
4118 	cred_t *cr,
4119 	caller_context_t *ct)
4120 {
4121 	int	err;
4122 
4123 	VOPXID_MAP_CR(vp, cr);
4124 
4125 	/*
4126 	 * We're only allowed to skip the ACL check iff we used a 32 bit
4127 	 * ACE mask with VOP_ACCESS() to determine permissions.
4128 	 */
4129 	if ((flag & ATTR_NOACLCHECK) &&
4130 	    vfs_has_feature(vp->v_vfsp, VFSFT_ACEMASKONACCESS) == 0) {
4131 		return (EINVAL);
4132 	}
4133 	err = (*(vp)->v_op->vop_setsecattr) (vp, vsap, flag, cr, ct);
4134 	VOPSTATS_UPDATE(vp, setsecattr);
4135 	return (err);
4136 }
4137 
4138 int
4139 fop_getsecattr(
4140 	vnode_t *vp,
4141 	vsecattr_t *vsap,
4142 	int flag,
4143 	cred_t *cr,
4144 	caller_context_t *ct)
4145 {
4146 	int	err;
4147 
4148 	/*
4149 	 * We're only allowed to skip the ACL check iff we used a 32 bit
4150 	 * ACE mask with VOP_ACCESS() to determine permissions.
4151 	 */
4152 	if ((flag & ATTR_NOACLCHECK) &&
4153 	    vfs_has_feature(vp->v_vfsp, VFSFT_ACEMASKONACCESS) == 0) {
4154 		return (EINVAL);
4155 	}
4156 
4157 	VOPXID_MAP_CR(vp, cr);
4158 
4159 	err = (*(vp)->v_op->vop_getsecattr) (vp, vsap, flag, cr, ct);
4160 	VOPSTATS_UPDATE(vp, getsecattr);
4161 	return (err);
4162 }
4163 
4164 int
4165 fop_shrlock(
4166 	vnode_t *vp,
4167 	int cmd,
4168 	struct shrlock *shr,
4169 	int flag,
4170 	cred_t *cr,
4171 	caller_context_t *ct)
4172 {
4173 	int	err;
4174 
4175 	VOPXID_MAP_CR(vp, cr);
4176 
4177 	err = (*(vp)->v_op->vop_shrlock)(vp, cmd, shr, flag, cr, ct);
4178 	VOPSTATS_UPDATE(vp, shrlock);
4179 	return (err);
4180 }
4181 
4182 int
4183 fop_vnevent(vnode_t *vp, vnevent_t vnevent, vnode_t *dvp, char *fnm,
4184     caller_context_t *ct)
4185 {
4186 	int	err;
4187 
4188 	err = (*(vp)->v_op->vop_vnevent)(vp, vnevent, dvp, fnm, ct);
4189 	VOPSTATS_UPDATE(vp, vnevent);
4190 	return (err);
4191 }
4192 
4193 int
4194 fop_reqzcbuf(vnode_t *vp, enum uio_rw ioflag, xuio_t *uiop, cred_t *cr,
4195     caller_context_t *ct)
4196 {
4197 	int err;
4198 
4199 	if (vfs_has_feature(vp->v_vfsp, VFSFT_ZEROCOPY_SUPPORTED) == 0)
4200 		return (ENOTSUP);
4201 	err = (*(vp)->v_op->vop_reqzcbuf)(vp, ioflag, uiop, cr, ct);
4202 	VOPSTATS_UPDATE(vp, reqzcbuf);
4203 	return (err);
4204 }
4205 
4206 int
4207 fop_retzcbuf(vnode_t *vp, xuio_t *uiop, cred_t *cr, caller_context_t *ct)
4208 {
4209 	int err;
4210 
4211 	if (vfs_has_feature(vp->v_vfsp, VFSFT_ZEROCOPY_SUPPORTED) == 0)
4212 		return (ENOTSUP);
4213 	err = (*(vp)->v_op->vop_retzcbuf)(vp, uiop, cr, ct);
4214 	VOPSTATS_UPDATE(vp, retzcbuf);
4215 	return (err);
4216 }
4217 
4218 /*
4219  * Default destructor
4220  *	Needed because NULL destructor means that the key is unused
4221  */
4222 /* ARGSUSED */
4223 void
4224 vsd_defaultdestructor(void *value)
4225 {}
4226 
4227 /*
4228  * Create a key (index into per vnode array)
4229  *	Locks out vsd_create, vsd_destroy, and vsd_free
4230  *	May allocate memory with lock held
4231  */
4232 void
4233 vsd_create(uint_t *keyp, void (*destructor)(void *))
4234 {
4235 	int	i;
4236 	uint_t	nkeys;
4237 
4238 	/*
4239 	 * if key is allocated, do nothing
4240 	 */
4241 	mutex_enter(&vsd_lock);
4242 	if (*keyp) {
4243 		mutex_exit(&vsd_lock);
4244 		return;
4245 	}
4246 	/*
4247 	 * find an unused key
4248 	 */
4249 	if (destructor == NULL)
4250 		destructor = vsd_defaultdestructor;
4251 
4252 	for (i = 0; i < vsd_nkeys; ++i)
4253 		if (vsd_destructor[i] == NULL)
4254 			break;
4255 
4256 	/*
4257 	 * if no unused keys, increase the size of the destructor array
4258 	 */
4259 	if (i == vsd_nkeys) {
4260 		if ((nkeys = (vsd_nkeys << 1)) == 0)
4261 			nkeys = 1;
4262 		vsd_destructor =
4263 		    (void (**)(void *))vsd_realloc((void *)vsd_destructor,
4264 		    (size_t)(vsd_nkeys * sizeof (void (*)(void *))),
4265 		    (size_t)(nkeys * sizeof (void (*)(void *))));
4266 		vsd_nkeys = nkeys;
4267 	}
4268 
4269 	/*
4270 	 * allocate the next available unused key
4271 	 */
4272 	vsd_destructor[i] = destructor;
4273 	*keyp = i + 1;
4274 
4275 	/* create vsd_list, if it doesn't exist */
4276 	if (vsd_list == NULL) {
4277 		vsd_list = kmem_alloc(sizeof (list_t), KM_SLEEP);
4278 		list_create(vsd_list, sizeof (struct vsd_node),
4279 		    offsetof(struct vsd_node, vs_nodes));
4280 	}
4281 
4282 	mutex_exit(&vsd_lock);
4283 }
4284 
4285 /*
4286  * Destroy a key
4287  *
4288  * Assumes that the caller is preventing vsd_set and vsd_get
4289  * Locks out vsd_create, vsd_destroy, and vsd_free
4290  * May free memory with lock held
4291  */
4292 void
4293 vsd_destroy(uint_t *keyp)
4294 {
4295 	uint_t key;
4296 	struct vsd_node *vsd;
4297 
4298 	/*
4299 	 * protect the key namespace and our destructor lists
4300 	 */
4301 	mutex_enter(&vsd_lock);
4302 	key = *keyp;
4303 	*keyp = 0;
4304 
4305 	ASSERT(key <= vsd_nkeys);
4306 
4307 	/*
4308 	 * if the key is valid
4309 	 */
4310 	if (key != 0) {
4311 		uint_t k = key - 1;
4312 		/*
4313 		 * for every vnode with VSD, call key's destructor
4314 		 */
4315 		for (vsd = list_head(vsd_list); vsd != NULL;
4316 		    vsd = list_next(vsd_list, vsd)) {
4317 			/*
4318 			 * no VSD for key in this vnode
4319 			 */
4320 			if (key > vsd->vs_nkeys)
4321 				continue;
4322 			/*
4323 			 * call destructor for key
4324 			 */
4325 			if (vsd->vs_value[k] && vsd_destructor[k])
4326 				(*vsd_destructor[k])(vsd->vs_value[k]);
4327 			/*
4328 			 * reset value for key
4329 			 */
4330 			vsd->vs_value[k] = NULL;
4331 		}
4332 		/*
4333 		 * actually free the key (NULL destructor == unused)
4334 		 */
4335 		vsd_destructor[k] = NULL;
4336 	}
4337 
4338 	mutex_exit(&vsd_lock);
4339 }
4340 
4341 /*
4342  * Quickly return the per vnode value that was stored with the specified key
4343  * Assumes the caller is protecting key from vsd_create and vsd_destroy
4344  * Assumes the caller is holding v_vsd_lock to protect the vsd.
4345  */
4346 void *
4347 vsd_get(vnode_t *vp, uint_t key)
4348 {
4349 	struct vsd_node *vsd;
4350 
4351 	ASSERT(vp != NULL);
4352 	ASSERT(mutex_owned(&vp->v_vsd_lock));
4353 
4354 	vsd = vp->v_vsd;
4355 
4356 	if (key && vsd != NULL && key <= vsd->vs_nkeys)
4357 		return (vsd->vs_value[key - 1]);
4358 	return (NULL);
4359 }
4360 
4361 /*
4362  * Set a per vnode value indexed with the specified key
4363  * Assumes the caller is holding v_vsd_lock to protect the vsd.
4364  */
4365 int
4366 vsd_set(vnode_t *vp, uint_t key, void *value)
4367 {
4368 	struct vsd_node *vsd;
4369 
4370 	ASSERT(vp != NULL);
4371 	ASSERT(mutex_owned(&vp->v_vsd_lock));
4372 
4373 	if (key == 0)
4374 		return (EINVAL);
4375 
4376 	vsd = vp->v_vsd;
4377 	if (vsd == NULL)
4378 		vsd = vp->v_vsd = kmem_zalloc(sizeof (*vsd), KM_SLEEP);
4379 
4380 	/*
4381 	 * If the vsd was just allocated, vs_nkeys will be 0, so the following
4382 	 * code won't happen and we will continue down and allocate space for
4383 	 * the vs_value array.
4384 	 * If the caller is replacing one value with another, then it is up
4385 	 * to the caller to free/rele/destroy the previous value (if needed).
4386 	 */
4387 	if (key <= vsd->vs_nkeys) {
4388 		vsd->vs_value[key - 1] = value;
4389 		return (0);
4390 	}
4391 
4392 	ASSERT(key <= vsd_nkeys);
4393 
4394 	if (vsd->vs_nkeys == 0) {
4395 		mutex_enter(&vsd_lock);	/* lock out vsd_destroy() */
4396 		/*
4397 		 * Link onto list of all VSD nodes.
4398 		 */
4399 		list_insert_head(vsd_list, vsd);
4400 		mutex_exit(&vsd_lock);
4401 	}
4402 
4403 	/*
4404 	 * Allocate vnode local storage and set the value for key
4405 	 */
4406 	vsd->vs_value = vsd_realloc(vsd->vs_value,
4407 	    vsd->vs_nkeys * sizeof (void *),
4408 	    key * sizeof (void *));
4409 	vsd->vs_nkeys = key;
4410 	vsd->vs_value[key - 1] = value;
4411 
4412 	return (0);
4413 }
4414 
4415 /*
4416  * Called from vn_free() to run the destructor function for each vsd
4417  *	Locks out vsd_create and vsd_destroy
4418  *	Assumes that the destructor *DOES NOT* use vsd
4419  */
4420 void
4421 vsd_free(vnode_t *vp)
4422 {
4423 	int i;
4424 	struct vsd_node *vsd = vp->v_vsd;
4425 
4426 	if (vsd == NULL)
4427 		return;
4428 
4429 	if (vsd->vs_nkeys == 0) {
4430 		kmem_free(vsd, sizeof (*vsd));
4431 		vp->v_vsd = NULL;
4432 		return;
4433 	}
4434 
4435 	/*
4436 	 * lock out vsd_create and vsd_destroy, call
4437 	 * the destructor, and mark the value as destroyed.
4438 	 */
4439 	mutex_enter(&vsd_lock);
4440 
4441 	for (i = 0; i < vsd->vs_nkeys; i++) {
4442 		if (vsd->vs_value[i] && vsd_destructor[i])
4443 			(*vsd_destructor[i])(vsd->vs_value[i]);
4444 		vsd->vs_value[i] = NULL;
4445 	}
4446 
4447 	/*
4448 	 * remove from linked list of VSD nodes
4449 	 */
4450 	list_remove(vsd_list, vsd);
4451 
4452 	mutex_exit(&vsd_lock);
4453 
4454 	/*
4455 	 * free up the VSD
4456 	 */
4457 	kmem_free(vsd->vs_value, vsd->vs_nkeys * sizeof (void *));
4458 	kmem_free(vsd, sizeof (struct vsd_node));
4459 	vp->v_vsd = NULL;
4460 }
4461 
4462 /*
4463  * realloc
4464  */
4465 static void *
4466 vsd_realloc(void *old, size_t osize, size_t nsize)
4467 {
4468 	void *new;
4469 
4470 	new = kmem_zalloc(nsize, KM_SLEEP);
4471 	if (old) {
4472 		bcopy(old, new, osize);
4473 		kmem_free(old, osize);
4474 	}
4475 	return (new);
4476 }
4477 
4478 /*
4479  * Setup the extensible system attribute for creating a reparse point.
4480  * The symlink data 'target' is validated for proper format of a reparse
4481  * string and a check also made to make sure the symlink data does not
4482  * point to an existing file.
4483  *
4484  * return 0 if ok else -1.
4485  */
4486 static int
4487 fs_reparse_mark(char *target, vattr_t *vap, xvattr_t *xvattr)
4488 {
4489 	xoptattr_t *xoap;
4490 
4491 	if ((!target) || (!vap) || (!xvattr))
4492 		return (-1);
4493 
4494 	/* validate reparse string */
4495 	if (reparse_validate((const char *)target))
4496 		return (-1);
4497 
4498 	xva_init(xvattr);
4499 	xvattr->xva_vattr = *vap;
4500 	xvattr->xva_vattr.va_mask |= AT_XVATTR;
4501 	xoap = xva_getxoptattr(xvattr);
4502 	ASSERT(xoap);
4503 	XVA_SET_REQ(xvattr, XAT_REPARSE);
4504 	xoap->xoa_reparse = 1;
4505 
4506 	return (0);
4507 }
4508 
4509 /*
4510  * Function to check whether a symlink is a reparse point.
4511  * Return B_TRUE if it is a reparse point, else return B_FALSE
4512  */
4513 boolean_t
4514 vn_is_reparse(vnode_t *vp, cred_t *cr, caller_context_t *ct)
4515 {
4516 	xvattr_t xvattr;
4517 	xoptattr_t *xoap;
4518 
4519 	if ((vp->v_type != VLNK) ||
4520 	    !(vfs_has_feature(vp->v_vfsp, VFSFT_XVATTR)))
4521 		return (B_FALSE);
4522 
4523 	xva_init(&xvattr);
4524 	xoap = xva_getxoptattr(&xvattr);
4525 	ASSERT(xoap);
4526 	XVA_SET_REQ(&xvattr, XAT_REPARSE);
4527 
4528 	if (VOP_GETATTR(vp, &xvattr.xva_vattr, 0, cr, ct))
4529 		return (B_FALSE);
4530 
4531 	if ((!(xvattr.xva_vattr.va_mask & AT_XVATTR)) ||
4532 	    (!(XVA_ISSET_RTN(&xvattr, XAT_REPARSE))))
4533 		return (B_FALSE);
4534 
4535 	return (xoap->xoa_reparse ? B_TRUE : B_FALSE);
4536 }
4537