xref: /netbsd-src/sys/kern/vfs_syscalls.c (revision 1ad9454efb13a65cd7535ccf867508cb14d9d30e)
1 /*	$NetBSD: vfs_syscalls.c,v 1.270 2006/09/13 10:07:42 elad Exp $	*/
2 
3 /*
4  * Copyright (c) 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)vfs_syscalls.c	8.42 (Berkeley) 7/31/95
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_syscalls.c,v 1.270 2006/09/13 10:07:42 elad Exp $");
41 
42 #include "opt_compat_netbsd.h"
43 #include "opt_compat_43.h"
44 #include "opt_fileassoc.h"
45 #include "opt_ktrace.h"
46 #include "fss.h"
47 #include "veriexec.h"
48 
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/namei.h>
52 #include <sys/filedesc.h>
53 #include <sys/kernel.h>
54 #include <sys/file.h>
55 #include <sys/stat.h>
56 #include <sys/vnode.h>
57 #include <sys/mount.h>
58 #include <sys/proc.h>
59 #include <sys/uio.h>
60 #include <sys/malloc.h>
61 #include <sys/kmem.h>
62 #include <sys/dirent.h>
63 #include <sys/sysctl.h>
64 #include <sys/sa.h>
65 #include <sys/syscallargs.h>
66 #ifdef KTRACE
67 #include <sys/ktrace.h>
68 #endif
69 #ifdef FILEASSOC
70 #include <sys/fileassoc.h>
71 #endif /* FILEASSOC */
72 #if NVERIEXEC > 0
73 #include <sys/verified_exec.h>
74 #endif /* NVERIEXEC > 0 */
75 #include <sys/kauth.h>
76 
77 #include <miscfs/genfs/genfs.h>
78 #include <miscfs/syncfs/syncfs.h>
79 
80 #ifdef COMPAT_30
81 #include "opt_nfsserver.h"
82 #include <nfs/rpcv2.h>
83 #endif
84 #include <nfs/nfsproto.h>
85 #ifdef COMPAT_30
86 #include <nfs/nfs.h>
87 #include <nfs/nfs_var.h>
88 #endif
89 
90 #if NFSS > 0
91 #include <dev/fssvar.h>
92 #endif
93 
94 MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount struct");
95 
96 static int change_dir(struct nameidata *, struct lwp *);
97 static int change_flags(struct vnode *, u_long, struct lwp *);
98 static int change_mode(struct vnode *, int, struct lwp *l);
99 static int change_owner(struct vnode *, uid_t, gid_t, struct lwp *, int);
100 static int change_utimes(struct vnode *vp, const struct timeval *,
101 	       struct lwp *l);
102 static int rename_files(const char *, const char *, struct lwp *, int);
103 
104 void checkdirs(struct vnode *);
105 
106 int dovfsusermount = 0;
107 
108 /*
109  * Virtual File System System Calls
110  */
111 
112 /*
113  * Mount a file system.
114  */
115 
116 #if defined(COMPAT_09) || defined(COMPAT_43)
117 /*
118  * This table is used to maintain compatibility with 4.3BSD
119  * and NetBSD 0.9 mount syscalls.  Note, the order is important!
120  *
121  * Do not modify this table. It should only contain filesystems
122  * supported by NetBSD 0.9 and 4.3BSD.
123  */
124 const char * const mountcompatnames[] = {
125 	NULL,		/* 0 = MOUNT_NONE */
126 	MOUNT_FFS,	/* 1 = MOUNT_UFS */
127 	MOUNT_NFS,	/* 2 */
128 	MOUNT_MFS,	/* 3 */
129 	MOUNT_MSDOS,	/* 4 */
130 	MOUNT_CD9660,	/* 5 = MOUNT_ISOFS */
131 	MOUNT_FDESC,	/* 6 */
132 	MOUNT_KERNFS,	/* 7 */
133 	NULL,		/* 8 = MOUNT_DEVFS */
134 	MOUNT_AFS,	/* 9 */
135 };
136 const int nmountcompatnames = sizeof(mountcompatnames) /
137     sizeof(mountcompatnames[0]);
138 #endif /* COMPAT_09 || COMPAT_43 */
139 
140 /* ARGSUSED */
141 int
142 sys_mount(struct lwp *l, void *v, register_t *retval)
143 {
144 	struct sys_mount_args /* {
145 		syscallarg(const char *) type;
146 		syscallarg(const char *) path;
147 		syscallarg(int) flags;
148 		syscallarg(void *) data;
149 	} */ *uap = v;
150 	struct vnode *vp;
151 	struct mount *mp;
152 	int error, flag = 0;
153 	char fstypename[MFSNAMELEN];
154 	struct vattr va;
155 	struct nameidata nd;
156 	struct vfsops *vfs;
157 
158 	/*
159 	 * if MNT_GETARGS is specified, it should be only flag.
160 	 */
161 
162 	if ((SCARG(uap, flags) & MNT_GETARGS) != 0 &&
163 	    (SCARG(uap, flags) & ~MNT_GETARGS) != 0) {
164 		return EINVAL;
165 	}
166 
167 	if (dovfsusermount == 0 && (SCARG(uap, flags) & MNT_GETARGS) == 0 &&
168 	    (error = kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER,
169 	    &l->l_acflag)))
170 		return (error);
171 	/*
172 	 * Get vnode to be covered
173 	 */
174 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE,
175 	    SCARG(uap, path), l);
176 	if ((error = namei(&nd)) != 0)
177 		return (error);
178 	vp = nd.ni_vp;
179 	/*
180 	 * A lookup in VFS_MOUNT might result in an attempt to
181 	 * lock this vnode again, so make the lock recursive.
182 	 */
183 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY | LK_SETRECURSE);
184 	if (SCARG(uap, flags) & (MNT_UPDATE | MNT_GETARGS)) {
185 		if ((vp->v_flag & VROOT) == 0) {
186 			vput(vp);
187 			return (EINVAL);
188 		}
189 		mp = vp->v_mount;
190 		flag = mp->mnt_flag;
191 		vfs = mp->mnt_op;
192 		/*
193 		 * We only allow the filesystem to be reloaded if it
194 		 * is currently mounted read-only.
195 		 */
196 		if ((SCARG(uap, flags) & MNT_RELOAD) &&
197 		    ((mp->mnt_flag & MNT_RDONLY) == 0)) {
198 			vput(vp);
199 			return (EOPNOTSUPP);	/* Needs translation */
200 		}
201 		/*
202 		 * In "highly secure" mode, don't let the caller do anything
203 		 * but downgrade a filesystem from read-write to read-only.
204 		 * (see also below; MNT_UPDATE or MNT_GETARGS is required.)
205 		 */
206 		if (securelevel >= 2 &&
207 		    SCARG(uap, flags) != MNT_GETARGS &&
208 		    SCARG(uap, flags) !=
209 		    (mp->mnt_flag | MNT_RDONLY |
210 		     MNT_RELOAD | MNT_FORCE | MNT_UPDATE)) {
211 			vput(vp);
212 			return (EPERM);
213 		}
214 		mp->mnt_flag |= SCARG(uap, flags) &
215 		    (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_GETARGS);
216 		/*
217 		 * Only root, or the user that did the original mount is
218 		 * permitted to update it.
219 		 */
220 		if ((mp->mnt_flag & MNT_GETARGS) == 0 &&
221 		    mp->mnt_stat.f_owner != kauth_cred_geteuid(l->l_cred) &&
222 		    (error = kauth_authorize_generic(l->l_cred,
223 		    KAUTH_GENERIC_ISSUSER, &l->l_acflag)) != 0) {
224 			vput(vp);
225 			return (error);
226 		}
227 		/*
228 		 * Do not allow NFS export by non-root users. For non-root
229 		 * users, silently enforce MNT_NOSUID and MNT_NODEV, and
230 		 * MNT_NOEXEC if mount point is already MNT_NOEXEC.
231 		 */
232 		if (kauth_cred_geteuid(l->l_cred) != 0) {
233 			if (SCARG(uap, flags) & MNT_EXPORTED) {
234 				vput(vp);
235 				return (EPERM);
236 			}
237 			SCARG(uap, flags) |= MNT_NOSUID | MNT_NODEV;
238 			if (flag & MNT_NOEXEC)
239 				SCARG(uap, flags) |= MNT_NOEXEC;
240 		}
241 		if (vfs_busy(mp, LK_NOWAIT, 0)) {
242 			vput(vp);
243 			return (EPERM);
244 		}
245 		goto update;
246 	} else {
247 		if (securelevel >= 2) {
248 			vput(vp);
249 			return (EPERM);
250 		}
251 	}
252 	/*
253 	 * If the user is not root, ensure that they own the directory
254 	 * onto which we are attempting to mount.
255 	 */
256 	if ((error = VOP_GETATTR(vp, &va, l->l_cred, l)) != 0 ||
257 	    (va.va_uid != kauth_cred_geteuid(l->l_cred) &&
258 		(error = kauth_authorize_generic(l->l_cred,
259 	 	KAUTH_GENERIC_ISSUSER, &l->l_acflag)) != 0)) {
260 		vput(vp);
261 		return (error);
262 	}
263 	/*
264 	 * Do not allow NFS export by non-root users. For non-root users,
265 	 * silently enforce MNT_NOSUID and MNT_NODEV, and MNT_NOEXEC if the
266 	 * mount point is already MNT_NOEXEC.
267 	 */
268 	if (kauth_cred_geteuid(l->l_cred) != 0) {
269 		if (SCARG(uap, flags) & MNT_EXPORTED) {
270 			vput(vp);
271 			return (EPERM);
272 		}
273 		SCARG(uap, flags) |= MNT_NOSUID | MNT_NODEV;
274 		if (vp->v_mount->mnt_flag & MNT_NOEXEC)
275 			SCARG(uap, flags) |= MNT_NOEXEC;
276 	}
277 	if ((error = vinvalbuf(vp, V_SAVE, l->l_cred, l, 0, 0)) != 0) {
278 		vput(vp);
279 		return (error);
280 	}
281 	if (vp->v_type != VDIR) {
282 		vput(vp);
283 		return (ENOTDIR);
284 	}
285 	error = copyinstr(SCARG(uap, type), fstypename, MFSNAMELEN, NULL);
286 	if (error) {
287 #if defined(COMPAT_09) || defined(COMPAT_43)
288 		/*
289 		 * Historically, filesystem types were identified by numbers.
290 		 * If we get an integer for the filesystem type instead of a
291 		 * string, we check to see if it matches one of the historic
292 		 * filesystem types.
293 		 */
294 		u_long fsindex = (u_long)SCARG(uap, type);
295 		if (fsindex >= nmountcompatnames ||
296 		    mountcompatnames[fsindex] == NULL) {
297 			vput(vp);
298 			return (ENODEV);
299 		}
300 		strncpy(fstypename, mountcompatnames[fsindex], MFSNAMELEN);
301 #else
302 		vput(vp);
303 		return (error);
304 #endif
305 	}
306 #ifdef	COMPAT_10
307 	/* Accept `ufs' as an alias for `ffs'. */
308 	if (!strncmp(fstypename, "ufs", MFSNAMELEN))
309 		strncpy(fstypename, "ffs", MFSNAMELEN);
310 #endif
311 	if ((vfs = vfs_getopsbyname(fstypename)) == NULL) {
312 		vput(vp);
313 		return (ENODEV);
314 	}
315 	if (vp->v_mountedhere != NULL) {
316 		vput(vp);
317 		return (EBUSY);
318 	}
319 
320 	/*
321 	 * Allocate and initialize the file system.
322 	 */
323 	mp = (struct mount *)malloc((u_long)sizeof(struct mount),
324 		M_MOUNT, M_WAITOK);
325 	memset((char *)mp, 0, (u_long)sizeof(struct mount));
326 	lockinit(&mp->mnt_lock, PVFS, "vfslock", 0, 0);
327 	simple_lock_init(&mp->mnt_slock);
328 	(void)vfs_busy(mp, LK_NOWAIT, 0);
329 	mp->mnt_op = vfs;
330 	vfs->vfs_refcount++;
331 	mp->mnt_vnodecovered = vp;
332 	mp->mnt_stat.f_owner = kauth_cred_geteuid(l->l_cred);
333 	mp->mnt_unmounter = NULL;
334 	mp->mnt_leaf = mp;
335 
336 	/*
337 	 * The underlying file system may refuse the mount for
338 	 * various reasons.  Allow the user to force it to happen.
339 	 */
340 	mp->mnt_flag |= SCARG(uap, flags) & MNT_FORCE;
341  update:
342 	if ((SCARG(uap, flags) & MNT_GETARGS) == 0) {
343 		/*
344 		 * Set the mount level flags.
345 		 */
346 		if (SCARG(uap, flags) & MNT_RDONLY)
347 			mp->mnt_flag |= MNT_RDONLY;
348 		else if (mp->mnt_flag & MNT_RDONLY)
349 			mp->mnt_iflag |= IMNT_WANTRDWR;
350 		mp->mnt_flag &=
351 		  ~(MNT_NOSUID | MNT_NOEXEC | MNT_NODEV |
352 		    MNT_SYNCHRONOUS | MNT_UNION | MNT_ASYNC | MNT_NOCOREDUMP |
353 		    MNT_NOATIME | MNT_NODEVMTIME | MNT_SYMPERM | MNT_SOFTDEP);
354 		mp->mnt_flag |= SCARG(uap, flags) &
355 		   (MNT_NOSUID | MNT_NOEXEC | MNT_NODEV |
356 		    MNT_SYNCHRONOUS | MNT_UNION | MNT_ASYNC | MNT_NOCOREDUMP |
357 		    MNT_NOATIME | MNT_NODEVMTIME | MNT_SYMPERM | MNT_SOFTDEP |
358 		    MNT_IGNORE);
359 	}
360 	/*
361 	 * Mount the filesystem.
362 	 */
363 	error = VFS_MOUNT(mp, SCARG(uap, path), SCARG(uap, data), &nd, l);
364 	if (mp->mnt_flag & (MNT_UPDATE | MNT_GETARGS)) {
365 #if defined(COMPAT_30) && defined(NFSSERVER)
366 		if (mp->mnt_flag & MNT_UPDATE && error != 0) {
367 			int error2;
368 
369 			/* Update failed; let's try and see if it was an
370 			 * export request. */
371 			error2 = nfs_update_exports_30(mp, SCARG(uap, path),
372 			    SCARG(uap, data), l);
373 
374 			/* Only update error code if the export request was
375 			 * understood but some problem occurred while
376 			 * processing it. */
377 			if (error2 != EJUSTRETURN)
378 				error = error2;
379 		}
380 #endif
381 		if (mp->mnt_iflag & IMNT_WANTRDWR)
382 			mp->mnt_flag &= ~MNT_RDONLY;
383 		if (error)
384 			mp->mnt_flag = flag;
385 		mp->mnt_flag &=~
386 		    (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_GETARGS);
387 		mp->mnt_iflag &=~ IMNT_WANTRDWR;
388 		if ((mp->mnt_flag & (MNT_RDONLY | MNT_ASYNC)) == 0) {
389 			if (mp->mnt_syncer == NULL)
390 				error = vfs_allocate_syncvnode(mp);
391 		} else {
392 			if (mp->mnt_syncer != NULL)
393 				vfs_deallocate_syncvnode(mp);
394 		}
395 		vfs_unbusy(mp);
396 		VOP_UNLOCK(vp, 0);
397 		vrele(vp);
398 		return (error);
399 	}
400 	/*
401 	 * Put the new filesystem on the mount list after root.
402 	 */
403 	cache_purge(vp);
404 	if (!error) {
405 		mp->mnt_flag &=~
406 		    (MNT_RELOAD | MNT_FORCE | MNT_UPDATE | MNT_GETARGS);
407 		mp->mnt_iflag &=~ IMNT_WANTRDWR;
408 		vp->v_mountedhere = mp;
409 		simple_lock(&mountlist_slock);
410 		CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
411 		simple_unlock(&mountlist_slock);
412 		checkdirs(vp);
413 		VOP_UNLOCK(vp, 0);
414 		if ((mp->mnt_flag & (MNT_RDONLY | MNT_ASYNC)) == 0)
415 			error = vfs_allocate_syncvnode(mp);
416 		vfs_unbusy(mp);
417 		(void) VFS_STATVFS(mp, &mp->mnt_stat, l);
418 		if ((error = VFS_START(mp, 0, l)))
419 			vrele(vp);
420 	} else {
421 		vp->v_mountedhere = (struct mount *)0;
422 		vfs->vfs_refcount--;
423 		vfs_unbusy(mp);
424 		free(mp, M_MOUNT);
425 		vput(vp);
426 	}
427 	return (error);
428 }
429 
430 /*
431  * Scan all active processes to see if any of them have a current
432  * or root directory onto which the new filesystem has just been
433  * mounted. If so, replace them with the new mount point.
434  */
435 void
436 checkdirs(struct vnode *olddp)
437 {
438 	struct cwdinfo *cwdi;
439 	struct vnode *newdp;
440 	struct proc *p;
441 
442 	if (olddp->v_usecount == 1)
443 		return;
444 	if (VFS_ROOT(olddp->v_mountedhere, &newdp))
445 		panic("mount: lost mount");
446 	proclist_lock_read();
447 	PROCLIST_FOREACH(p, &allproc) {
448 		cwdi = p->p_cwdi;
449 		if (!cwdi)
450 			continue;
451 		if (cwdi->cwdi_cdir == olddp) {
452 			vrele(cwdi->cwdi_cdir);
453 			VREF(newdp);
454 			cwdi->cwdi_cdir = newdp;
455 		}
456 		if (cwdi->cwdi_rdir == olddp) {
457 			vrele(cwdi->cwdi_rdir);
458 			VREF(newdp);
459 			cwdi->cwdi_rdir = newdp;
460 		}
461 	}
462 	proclist_unlock_read();
463 	if (rootvnode == olddp) {
464 		vrele(rootvnode);
465 		VREF(newdp);
466 		rootvnode = newdp;
467 	}
468 	vput(newdp);
469 }
470 
471 /*
472  * Unmount a file system.
473  *
474  * Note: unmount takes a path to the vnode mounted on as argument,
475  * not special file (as before).
476  */
477 /* ARGSUSED */
478 int
479 sys_unmount(struct lwp *l, void *v, register_t *retval)
480 {
481 	struct sys_unmount_args /* {
482 		syscallarg(const char *) path;
483 		syscallarg(int) flags;
484 	} */ *uap = v;
485 	struct vnode *vp;
486 	struct mount *mp;
487 	int error;
488 	struct nameidata nd;
489 
490 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
491 	    SCARG(uap, path), l);
492 	if ((error = namei(&nd)) != 0)
493 		return (error);
494 	vp = nd.ni_vp;
495 	mp = vp->v_mount;
496 
497 	/*
498 	 * Only root, or the user that did the original mount is
499 	 * permitted to unmount this filesystem.
500 	 */
501 	if ((mp->mnt_stat.f_owner != kauth_cred_geteuid(l->l_cred)) &&
502 	    (error = kauth_authorize_generic(l->l_cred,
503 	 	KAUTH_GENERIC_ISSUSER, &l->l_acflag)) != 0) {
504 		vput(vp);
505 		return (error);
506 	}
507 
508 	/*
509 	 * Don't allow unmounting the root file system.
510 	 */
511 	if (mp->mnt_flag & MNT_ROOTFS) {
512 		vput(vp);
513 		return (EINVAL);
514 	}
515 
516 	/*
517 	 * Must be the root of the filesystem
518 	 */
519 	if ((vp->v_flag & VROOT) == 0) {
520 		vput(vp);
521 		return (EINVAL);
522 	}
523 	vput(vp);
524 
525 	/*
526 	 * XXX Freeze syncer.  Must do this before locking the
527 	 * mount point.  See dounmount() for details.
528 	 */
529 	lockmgr(&syncer_lock, LK_EXCLUSIVE, NULL);
530 
531 	if (vfs_busy(mp, 0, 0)) {
532 		lockmgr(&syncer_lock, LK_RELEASE, NULL);
533 		return (EBUSY);
534 	}
535 
536 	return (dounmount(mp, SCARG(uap, flags), l));
537 }
538 
539 /*
540  * Do the actual file system unmount. File system is assumed to have been
541  * marked busy by the caller.
542  */
543 int
544 dounmount(struct mount *mp, int flags, struct lwp *l)
545 {
546 	struct vnode *coveredvp;
547 	int error;
548 	int async;
549 	int used_syncer;
550 
551 #if NVERIEXEC > 0
552 	if (!doing_shutdown) {
553 		if (veriexec_strict >= VERIEXEC_LOCKDOWN) {
554 			printf("Veriexec: Lockdown mode, preventing unmount of"
555 			    " \"%s\". (uid=%u)\n", mp->mnt_stat.f_mntonname,
556 			    kauth_cred_getuid(l->l_cred));
557 			return (EPERM);
558 		}
559 
560 		if (veriexec_strict == VERIEXEC_IPS) {
561 			struct veriexec_table_entry *vte;
562 
563 			/* Check if we have fingerprints on mount. */
564 			vte = fileassoc_tabledata_lookup(mp, veriexec_hook);
565 			if ((vte != NULL) && (vte->vte_count > 0)) {
566 				printf("Veriexec: IPS mode, preventing unmount"
567 				    " of \"%s\" with monitored files. "
568 				    "(uid=%u)\n", mp->mnt_stat.f_mntonname,
569 				    kauth_cred_getuid(l->l_cred));
570 				return (EPERM);
571 			}
572 		}
573 	}
574 #endif /* NVERIEXEC > 0 */
575 
576 #ifdef FILEASSOC
577 	(void)fileassoc_table_delete(mp);
578 #endif /* FILEASSOC */
579 
580 	simple_lock(&mountlist_slock);
581 	vfs_unbusy(mp);
582 	used_syncer = (mp->mnt_syncer != NULL);
583 
584 	/*
585 	 * XXX Syncer must be frozen when we get here.  This should really
586 	 * be done on a per-mountpoint basis, but especially the softdep
587 	 * code possibly called from the syncer doesn't exactly work on a
588 	 * per-mountpoint basis, so the softdep code would become a maze
589 	 * of vfs_busy() calls.
590 	 *
591 	 * The caller of dounmount() must acquire syncer_lock because
592 	 * the syncer itself acquires locks in syncer_lock -> vfs_busy
593 	 * order, and we must preserve that order to avoid deadlock.
594 	 *
595 	 * So, if the file system did not use the syncer, now is
596 	 * the time to release the syncer_lock.
597 	 */
598 	if (used_syncer == 0)
599 		lockmgr(&syncer_lock, LK_RELEASE, NULL);
600 
601 	mp->mnt_iflag |= IMNT_UNMOUNT;
602 	mp->mnt_unmounter = l;
603 	lockmgr(&mp->mnt_lock, LK_DRAIN | LK_INTERLOCK, &mountlist_slock);
604 	vn_start_write(NULL, &mp, V_WAIT);
605 
606 	async = mp->mnt_flag & MNT_ASYNC;
607 	mp->mnt_flag &= ~MNT_ASYNC;
608 	cache_purgevfs(mp);	/* remove cache entries for this file sys */
609 	if (mp->mnt_syncer != NULL)
610 		vfs_deallocate_syncvnode(mp);
611 	error = 0;
612 	if ((mp->mnt_flag & MNT_RDONLY) == 0) {
613 #if NFSS > 0
614 		error = fss_umount_hook(mp, (flags & MNT_FORCE));
615 #endif
616 		if (error == 0)
617 			error = VFS_SYNC(mp, MNT_WAIT, l->l_cred, l);
618 	}
619 	if (error == 0 || (flags & MNT_FORCE))
620 		error = VFS_UNMOUNT(mp, flags, l);
621 	vn_finished_write(mp, 0);
622 	simple_lock(&mountlist_slock);
623 	if (error) {
624 		if ((mp->mnt_flag & (MNT_RDONLY | MNT_ASYNC)) == 0)
625 			(void) vfs_allocate_syncvnode(mp);
626 		mp->mnt_iflag &= ~IMNT_UNMOUNT;
627 		mp->mnt_unmounter = NULL;
628 		mp->mnt_flag |= async;
629 		lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK | LK_REENABLE,
630 		    &mountlist_slock);
631 		if (used_syncer)
632 			lockmgr(&syncer_lock, LK_RELEASE, NULL);
633 		simple_lock(&mp->mnt_slock);
634 		while (mp->mnt_wcnt > 0) {
635 			wakeup(mp);
636 			ltsleep(&mp->mnt_wcnt, PVFS, "mntwcnt1",
637 				0, &mp->mnt_slock);
638 		}
639 		simple_unlock(&mp->mnt_slock);
640 		return (error);
641 	}
642 	CIRCLEQ_REMOVE(&mountlist, mp, mnt_list);
643 	if ((coveredvp = mp->mnt_vnodecovered) != NULLVP) {
644 		coveredvp->v_mountedhere = NULL;
645 		vrele(coveredvp);
646 	}
647 	mp->mnt_op->vfs_refcount--;
648 	if (LIST_FIRST(&mp->mnt_vnodelist) != NULL)
649 		panic("unmount: dangling vnode");
650 	mp->mnt_iflag |= IMNT_GONE;
651 	lockmgr(&mp->mnt_lock, LK_RELEASE | LK_INTERLOCK, &mountlist_slock);
652 	if (used_syncer)
653 		lockmgr(&syncer_lock, LK_RELEASE, NULL);
654 	simple_lock(&mp->mnt_slock);
655 	while (mp->mnt_wcnt > 0) {
656 		wakeup(mp);
657 		ltsleep(&mp->mnt_wcnt, PVFS, "mntwcnt2", 0, &mp->mnt_slock);
658 	}
659 	simple_unlock(&mp->mnt_slock);
660 	vfs_hooks_unmount(mp);
661 	free(mp, M_MOUNT);
662 	return (0);
663 }
664 
665 /*
666  * Sync each mounted filesystem.
667  */
668 #ifdef DEBUG
669 int syncprt = 0;
670 struct ctldebug debug0 = { "syncprt", &syncprt };
671 #endif
672 
673 /* ARGSUSED */
674 int
675 sys_sync(struct lwp *l, void *v, register_t *retval)
676 {
677 	struct mount *mp, *nmp;
678 	int asyncflag;
679 
680 	if (l == NULL)
681 		l = &lwp0;
682 
683 	simple_lock(&mountlist_slock);
684 	for (mp = mountlist.cqh_last; mp != (void *)&mountlist; mp = nmp) {
685 		if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock)) {
686 			nmp = mp->mnt_list.cqe_prev;
687 			continue;
688 		}
689 		if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
690 		    vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
691 			asyncflag = mp->mnt_flag & MNT_ASYNC;
692 			mp->mnt_flag &= ~MNT_ASYNC;
693 			VFS_SYNC(mp, MNT_NOWAIT, l->l_cred, l);
694 			if (asyncflag)
695 				 mp->mnt_flag |= MNT_ASYNC;
696 			vn_finished_write(mp, 0);
697 		}
698 		simple_lock(&mountlist_slock);
699 		nmp = mp->mnt_list.cqe_prev;
700 		vfs_unbusy(mp);
701 
702 	}
703 	simple_unlock(&mountlist_slock);
704 #ifdef DEBUG
705 	if (syncprt)
706 		vfs_bufstats();
707 #endif /* DEBUG */
708 	return (0);
709 }
710 
711 /*
712  * Change filesystem quotas.
713  */
714 /* ARGSUSED */
715 int
716 sys_quotactl(struct lwp *l, void *v, register_t *retval)
717 {
718 	struct sys_quotactl_args /* {
719 		syscallarg(const char *) path;
720 		syscallarg(int) cmd;
721 		syscallarg(int) uid;
722 		syscallarg(caddr_t) arg;
723 	} */ *uap = v;
724 	struct mount *mp;
725 	int error;
726 	struct nameidata nd;
727 
728 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
729 	if ((error = namei(&nd)) != 0)
730 		return (error);
731 	error = vn_start_write(nd.ni_vp, &mp, V_WAIT | V_PCATCH);
732 	vrele(nd.ni_vp);
733 	if (error)
734 		return (error);
735 	error = VFS_QUOTACTL(mp, SCARG(uap, cmd), SCARG(uap, uid),
736 	    SCARG(uap, arg), l);
737 	vn_finished_write(mp, 0);
738 	return (error);
739 }
740 
741 int
742 dostatvfs(struct mount *mp, struct statvfs *sp, struct lwp *l, int flags,
743     int root)
744 {
745 	struct cwdinfo *cwdi = l->l_proc->p_cwdi;
746 	int error = 0;
747 
748 	/*
749 	 * If MNT_NOWAIT or MNT_LAZY is specified, do not
750 	 * refresh the fsstat cache. MNT_WAIT or MNT_LAZY
751 	 * overrides MNT_NOWAIT.
752 	 */
753 	if (flags == MNT_NOWAIT	|| flags == MNT_LAZY ||
754 	    (flags != MNT_WAIT && flags != 0)) {
755 		memcpy(sp, &mp->mnt_stat, sizeof(*sp));
756 		goto done;
757 	}
758 
759 	/* Get the filesystem stats now */
760 	memset(sp, 0, sizeof(*sp));
761 	if ((error = VFS_STATVFS(mp, sp, l)) != 0) {
762 		return error;
763 	}
764 
765 	if (cwdi->cwdi_rdir == NULL)
766 		(void)memcpy(&mp->mnt_stat, sp, sizeof(mp->mnt_stat));
767 done:
768 	if (cwdi->cwdi_rdir != NULL) {
769 		size_t len;
770 		char *bp;
771 		char *path = PNBUF_GET();
772 		if (!path)
773 			return ENOMEM;
774 
775 		bp = path + MAXPATHLEN;
776 		*--bp = '\0';
777 		error = getcwd_common(cwdi->cwdi_rdir, rootvnode, &bp, path,
778 		    MAXPATHLEN / 2, 0, l);
779 		if (error) {
780 			PNBUF_PUT(path);
781 			return error;
782 		}
783 		len = strlen(bp);
784 		/*
785 		 * for mount points that are below our root, we can see
786 		 * them, so we fix up the pathname and return them. The
787 		 * rest we cannot see, so we don't allow viewing the
788 		 * data.
789 		 */
790 		if (strncmp(bp, sp->f_mntonname, len) == 0) {
791 			strlcpy(sp->f_mntonname, &sp->f_mntonname[len],
792 			    sizeof(sp->f_mntonname));
793 			if (sp->f_mntonname[0] == '\0')
794 				(void)strlcpy(sp->f_mntonname, "/",
795 				    sizeof(sp->f_mntonname));
796 		} else {
797 			if (root)
798 				(void)strlcpy(sp->f_mntonname, "/",
799 				    sizeof(sp->f_mntonname));
800 			else
801 				error = EPERM;
802 		}
803 		PNBUF_PUT(path);
804 	}
805 	sp->f_flag = mp->mnt_flag & MNT_VISFLAGMASK;
806 	return error;
807 }
808 
809 /*
810  * Get filesystem statistics.
811  */
812 /* ARGSUSED */
813 int
814 sys_statvfs1(struct lwp *l, void *v, register_t *retval)
815 {
816 	struct sys_statvfs1_args /* {
817 		syscallarg(const char *) path;
818 		syscallarg(struct statvfs *) buf;
819 		syscallarg(int) flags;
820 	} */ *uap = v;
821 	struct mount *mp;
822 	struct statvfs *sb;
823 	int error;
824 	struct nameidata nd;
825 
826 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
827 	if ((error = namei(&nd)) != 0)
828 		return error;
829 	mp = nd.ni_vp->v_mount;
830 	vrele(nd.ni_vp);
831 	sb = STATVFSBUF_GET();
832 	error = dostatvfs(mp, sb, l, SCARG(uap, flags), 1);
833 	if (error == 0) {
834 		error = copyout(sb, SCARG(uap, buf), sizeof(*sb));
835 	}
836 	STATVFSBUF_PUT(sb);
837 	return error;
838 }
839 
840 /*
841  * Get filesystem statistics.
842  */
843 /* ARGSUSED */
844 int
845 sys_fstatvfs1(struct lwp *l, void *v, register_t *retval)
846 {
847 	struct sys_fstatvfs1_args /* {
848 		syscallarg(int) fd;
849 		syscallarg(struct statvfs *) buf;
850 		syscallarg(int) flags;
851 	} */ *uap = v;
852 	struct proc *p = l->l_proc;
853 	struct file *fp;
854 	struct mount *mp;
855 	struct statvfs *sb;
856 	int error;
857 
858 	/* getvnode() will use the descriptor for us */
859 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
860 		return (error);
861 	mp = ((struct vnode *)fp->f_data)->v_mount;
862 	sb = STATVFSBUF_GET();
863 	if ((error = dostatvfs(mp, sb, l, SCARG(uap, flags), 1)) != 0)
864 		goto out;
865 	error = copyout(sb, SCARG(uap, buf), sizeof(*sb));
866  out:
867 	FILE_UNUSE(fp, l);
868 	STATVFSBUF_PUT(sb);
869 	return error;
870 }
871 
872 
873 /*
874  * Get statistics on all filesystems.
875  */
876 int
877 sys_getvfsstat(struct lwp *l, void *v, register_t *retval)
878 {
879 	struct sys_getvfsstat_args /* {
880 		syscallarg(struct statvfs *) buf;
881 		syscallarg(size_t) bufsize;
882 		syscallarg(int) flags;
883 	} */ *uap = v;
884 	int root = 0;
885 	struct proc *p = l->l_proc;
886 	struct mount *mp, *nmp;
887 	struct statvfs *sb;
888 	struct statvfs *sfsp;
889 	size_t count, maxcount;
890 	int error = 0;
891 
892 	sb = STATVFSBUF_GET();
893 	maxcount = SCARG(uap, bufsize) / sizeof(struct statvfs);
894 	sfsp = SCARG(uap, buf);
895 	simple_lock(&mountlist_slock);
896 	count = 0;
897 	for (mp = CIRCLEQ_FIRST(&mountlist); mp != (void *)&mountlist;
898 	     mp = nmp) {
899 		if (vfs_busy(mp, LK_NOWAIT, &mountlist_slock)) {
900 			nmp = CIRCLEQ_NEXT(mp, mnt_list);
901 			continue;
902 		}
903 		if (sfsp && count < maxcount) {
904 			error = dostatvfs(mp, sb, l, SCARG(uap, flags), 0);
905 			if (error) {
906 				simple_lock(&mountlist_slock);
907 				nmp = CIRCLEQ_NEXT(mp, mnt_list);
908 				vfs_unbusy(mp);
909 				continue;
910 			}
911 			error = copyout(sb, sfsp, sizeof(*sfsp));
912 			if (error) {
913 				vfs_unbusy(mp);
914 				goto out;
915 			}
916 			sfsp++;
917 			root |= strcmp(sb->f_mntonname, "/") == 0;
918 		}
919 		count++;
920 		simple_lock(&mountlist_slock);
921 		nmp = CIRCLEQ_NEXT(mp, mnt_list);
922 		vfs_unbusy(mp);
923 	}
924 	simple_unlock(&mountlist_slock);
925 	if (root == 0 && p->p_cwdi->cwdi_rdir) {
926 		/*
927 		 * fake a root entry
928 		 */
929 		if ((error = dostatvfs(p->p_cwdi->cwdi_rdir->v_mount, sb, l,
930 		    SCARG(uap, flags), 1)) != 0)
931 			goto out;
932 		if (sfsp)
933 			error = copyout(sb, sfsp, sizeof(*sfsp));
934 		count++;
935 	}
936 	if (sfsp && count > maxcount)
937 		*retval = maxcount;
938 	else
939 		*retval = count;
940 out:
941 	STATVFSBUF_PUT(sb);
942 	return error;
943 }
944 
945 /*
946  * Change current working directory to a given file descriptor.
947  */
948 /* ARGSUSED */
949 int
950 sys_fchdir(struct lwp *l, void *v, register_t *retval)
951 {
952 	struct sys_fchdir_args /* {
953 		syscallarg(int) fd;
954 	} */ *uap = v;
955 	struct proc *p = l->l_proc;
956 	struct filedesc *fdp = p->p_fd;
957 	struct cwdinfo *cwdi = p->p_cwdi;
958 	struct vnode *vp, *tdp;
959 	struct mount *mp;
960 	struct file *fp;
961 	int error;
962 
963 	/* getvnode() will use the descriptor for us */
964 	if ((error = getvnode(fdp, SCARG(uap, fd), &fp)) != 0)
965 		return (error);
966 	vp = (struct vnode *)fp->f_data;
967 
968 	VREF(vp);
969 	vn_lock(vp,  LK_EXCLUSIVE | LK_RETRY);
970 	if (vp->v_type != VDIR)
971 		error = ENOTDIR;
972 	else
973 		error = VOP_ACCESS(vp, VEXEC, l->l_cred, l);
974 	while (!error && (mp = vp->v_mountedhere) != NULL) {
975 		if (vfs_busy(mp, 0, 0))
976 			continue;
977 		error = VFS_ROOT(mp, &tdp);
978 		vfs_unbusy(mp);
979 		if (error)
980 			break;
981 		vput(vp);
982 		vp = tdp;
983 	}
984 	if (error) {
985 		vput(vp);
986 		goto out;
987 	}
988 	VOP_UNLOCK(vp, 0);
989 
990 	/*
991 	 * Disallow changing to a directory not under the process's
992 	 * current root directory (if there is one).
993 	 */
994 	if (cwdi->cwdi_rdir && !vn_isunder(vp, NULL, l)) {
995 		vrele(vp);
996 		error = EPERM;	/* operation not permitted */
997 		goto out;
998 	}
999 
1000 	vrele(cwdi->cwdi_cdir);
1001 	cwdi->cwdi_cdir = vp;
1002  out:
1003 	FILE_UNUSE(fp, l);
1004 	return (error);
1005 }
1006 
1007 /*
1008  * Change this process's notion of the root directory to a given file
1009  * descriptor.
1010  */
1011 int
1012 sys_fchroot(struct lwp *l, void *v, register_t *retval)
1013 {
1014 	struct sys_fchroot_args *uap = v;
1015 	struct proc *p = l->l_proc;
1016 	struct filedesc *fdp = p->p_fd;
1017 	struct cwdinfo *cwdi = p->p_cwdi;
1018 	struct vnode	*vp;
1019 	struct file	*fp;
1020 	int		 error;
1021 
1022 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_CHROOT,
1023  	    KAUTH_REQ_SYSTEM_CHROOT_FCHROOT, NULL, NULL, NULL)) != 0)
1024 		return error;
1025 	/* getvnode() will use the descriptor for us */
1026 	if ((error = getvnode(fdp, SCARG(uap, fd), &fp)) != 0)
1027 		return error;
1028 	vp = (struct vnode *) fp->f_data;
1029 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1030 	if (vp->v_type != VDIR)
1031 		error = ENOTDIR;
1032 	else
1033 		error = VOP_ACCESS(vp, VEXEC, l->l_cred, l);
1034 	VOP_UNLOCK(vp, 0);
1035 	if (error)
1036 		goto out;
1037 	VREF(vp);
1038 
1039 	/*
1040 	 * Prevent escaping from chroot by putting the root under
1041 	 * the working directory.  Silently chdir to / if we aren't
1042 	 * already there.
1043 	 */
1044 	if (!vn_isunder(cwdi->cwdi_cdir, vp, l)) {
1045 		/*
1046 		 * XXX would be more failsafe to change directory to a
1047 		 * deadfs node here instead
1048 		 */
1049 		vrele(cwdi->cwdi_cdir);
1050 		VREF(vp);
1051 		cwdi->cwdi_cdir = vp;
1052 	}
1053 
1054 	if (cwdi->cwdi_rdir != NULL)
1055 		vrele(cwdi->cwdi_rdir);
1056 	cwdi->cwdi_rdir = vp;
1057  out:
1058 	FILE_UNUSE(fp, l);
1059 	return (error);
1060 }
1061 
1062 /*
1063  * Change current working directory (``.'').
1064  */
1065 /* ARGSUSED */
1066 int
1067 sys_chdir(struct lwp *l, void *v, register_t *retval)
1068 {
1069 	struct sys_chdir_args /* {
1070 		syscallarg(const char *) path;
1071 	} */ *uap = v;
1072 	struct proc *p = l->l_proc;
1073 	struct cwdinfo *cwdi = p->p_cwdi;
1074 	int error;
1075 	struct nameidata nd;
1076 
1077 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
1078 	    SCARG(uap, path), l);
1079 	if ((error = change_dir(&nd, l)) != 0)
1080 		return (error);
1081 	vrele(cwdi->cwdi_cdir);
1082 	cwdi->cwdi_cdir = nd.ni_vp;
1083 	return (0);
1084 }
1085 
1086 /*
1087  * Change notion of root (``/'') directory.
1088  */
1089 /* ARGSUSED */
1090 int
1091 sys_chroot(struct lwp *l, void *v, register_t *retval)
1092 {
1093 	struct sys_chroot_args /* {
1094 		syscallarg(const char *) path;
1095 	} */ *uap = v;
1096 	struct proc *p = l->l_proc;
1097 	struct cwdinfo *cwdi = p->p_cwdi;
1098 	struct vnode *vp;
1099 	int error;
1100 	struct nameidata nd;
1101 
1102 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_CHROOT,
1103 	    KAUTH_REQ_SYSTEM_CHROOT_CHROOT, NULL, NULL, NULL)) != 0)
1104 		return (error);
1105 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
1106 	    SCARG(uap, path), l);
1107 	if ((error = change_dir(&nd, l)) != 0)
1108 		return (error);
1109 	if (cwdi->cwdi_rdir != NULL)
1110 		vrele(cwdi->cwdi_rdir);
1111 	vp = nd.ni_vp;
1112 	cwdi->cwdi_rdir = vp;
1113 
1114 	/*
1115 	 * Prevent escaping from chroot by putting the root under
1116 	 * the working directory.  Silently chdir to / if we aren't
1117 	 * already there.
1118 	 */
1119 	if (!vn_isunder(cwdi->cwdi_cdir, vp, l)) {
1120 		/*
1121 		 * XXX would be more failsafe to change directory to a
1122 		 * deadfs node here instead
1123 		 */
1124 		vrele(cwdi->cwdi_cdir);
1125 		VREF(vp);
1126 		cwdi->cwdi_cdir = vp;
1127 	}
1128 
1129 	return (0);
1130 }
1131 
1132 /*
1133  * Common routine for chroot and chdir.
1134  */
1135 static int
1136 change_dir(struct nameidata *ndp, struct lwp *l)
1137 {
1138 	struct vnode *vp;
1139 	int error;
1140 
1141 	if ((error = namei(ndp)) != 0)
1142 		return (error);
1143 	vp = ndp->ni_vp;
1144 	if (vp->v_type != VDIR)
1145 		error = ENOTDIR;
1146 	else
1147 		error = VOP_ACCESS(vp, VEXEC, l->l_cred, l);
1148 
1149 	if (error)
1150 		vput(vp);
1151 	else
1152 		VOP_UNLOCK(vp, 0);
1153 	return (error);
1154 }
1155 
1156 /*
1157  * Check permissions, allocate an open file structure,
1158  * and call the device open routine if any.
1159  */
1160 int
1161 sys_open(struct lwp *l, void *v, register_t *retval)
1162 {
1163 	struct sys_open_args /* {
1164 		syscallarg(const char *) path;
1165 		syscallarg(int) flags;
1166 		syscallarg(int) mode;
1167 	} */ *uap = v;
1168 	struct proc *p = l->l_proc;
1169 	struct cwdinfo *cwdi = p->p_cwdi;
1170 	struct filedesc *fdp = p->p_fd;
1171 	struct file *fp;
1172 	struct vnode *vp;
1173 	int flags, cmode;
1174 	int type, indx, error;
1175 	struct flock lf;
1176 	struct nameidata nd;
1177 
1178 	flags = FFLAGS(SCARG(uap, flags));
1179 	if ((flags & (FREAD | FWRITE)) == 0)
1180 		return (EINVAL);
1181 	/* falloc() will use the file descriptor for us */
1182 	if ((error = falloc(l, &fp, &indx)) != 0)
1183 		return (error);
1184 	cmode = ((SCARG(uap, mode) &~ cwdi->cwdi_cmask) & ALLPERMS) &~ S_ISTXT;
1185 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
1186 	l->l_dupfd = -indx - 1;			/* XXX check for fdopen */
1187 	if ((error = vn_open(&nd, flags, cmode)) != 0) {
1188 		FILE_UNUSE(fp, l);
1189 		fdp->fd_ofiles[indx] = NULL;
1190 		ffree(fp);
1191 		if ((error == EDUPFD || error == EMOVEFD) &&
1192 		    l->l_dupfd >= 0 &&			/* XXX from fdopen */
1193 		    (error =
1194 			dupfdopen(l, indx, l->l_dupfd, flags, error)) == 0) {
1195 			*retval = indx;
1196 			return (0);
1197 		}
1198 		if (error == ERESTART)
1199 			error = EINTR;
1200 		fdremove(fdp, indx);
1201 		return (error);
1202 	}
1203 	l->l_dupfd = 0;
1204 	vp = nd.ni_vp;
1205 	fp->f_flag = flags & FMASK;
1206 	fp->f_type = DTYPE_VNODE;
1207 	fp->f_ops = &vnops;
1208 	fp->f_data = vp;
1209 	if (flags & (O_EXLOCK | O_SHLOCK)) {
1210 		lf.l_whence = SEEK_SET;
1211 		lf.l_start = 0;
1212 		lf.l_len = 0;
1213 		if (flags & O_EXLOCK)
1214 			lf.l_type = F_WRLCK;
1215 		else
1216 			lf.l_type = F_RDLCK;
1217 		type = F_FLOCK;
1218 		if ((flags & FNONBLOCK) == 0)
1219 			type |= F_WAIT;
1220 		VOP_UNLOCK(vp, 0);
1221 		error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, type);
1222 		if (error) {
1223 			(void) vn_close(vp, fp->f_flag, fp->f_cred, l);
1224 			FILE_UNUSE(fp, l);
1225 			ffree(fp);
1226 			fdremove(fdp, indx);
1227 			return (error);
1228 		}
1229 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1230 		fp->f_flag |= FHASLOCK;
1231 	}
1232 	VOP_UNLOCK(vp, 0);
1233 	*retval = indx;
1234 	FILE_SET_MATURE(fp);
1235 	FILE_UNUSE(fp, l);
1236 	return (0);
1237 }
1238 
1239 static void
1240 vfs__fhfree(fhandle_t *fhp)
1241 {
1242 	size_t fhsize;
1243 
1244 	if (fhp == NULL) {
1245 		return;
1246 	}
1247 	fhsize = FHANDLE_SIZE(fhp);
1248 	kmem_free(fhp, fhsize);
1249 }
1250 
1251 /*
1252  * vfs_composefh: compose a filehandle.
1253  */
1254 
1255 int
1256 vfs_composefh(struct vnode *vp, fhandle_t *fhp, size_t *fh_size)
1257 {
1258 	struct mount *mp;
1259 	struct fid *fidp;
1260 	int error;
1261 	size_t needfhsize;
1262 	size_t fidsize;
1263 
1264 	mp = vp->v_mount;
1265 	if (mp->mnt_op->vfs_vptofh == NULL) {
1266 		return EOPNOTSUPP;
1267 	}
1268 	fidp = NULL;
1269 	if (*fh_size < FHANDLE_SIZE_MIN) {
1270 		fidsize = 0;
1271 	} else {
1272 		fidsize = *fh_size - offsetof(fhandle_t, fh_fid);
1273 		if (fhp != NULL) {
1274 			memset(fhp, 0, *fh_size);
1275 			fhp->fh_fsid = mp->mnt_stat.f_fsidx;
1276 			fidp = &fhp->fh_fid;
1277 		}
1278 	}
1279 	error = VFS_VPTOFH(vp, fidp, &fidsize);
1280 	needfhsize = FHANDLE_SIZE_FROM_FILEID_SIZE(fidsize);
1281 	if (error == 0 && *fh_size < needfhsize) {
1282 		error = E2BIG;
1283 	}
1284 	*fh_size = needfhsize;
1285 	return error;
1286 }
1287 
1288 int
1289 vfs_composefh_alloc(struct vnode *vp, fhandle_t **fhpp)
1290 {
1291 	struct mount *mp;
1292 	fhandle_t *fhp;
1293 	size_t fhsize;
1294 	size_t fidsize;
1295 	int error;
1296 
1297 	*fhpp = NULL;
1298 	mp = vp->v_mount;
1299 	if (mp->mnt_op->vfs_vptofh == NULL) {
1300 		error = EOPNOTSUPP;
1301 		goto out;
1302 	}
1303 	fidsize = 0;
1304 	error = VFS_VPTOFH(vp, NULL, &fidsize);
1305 	KASSERT(error != 0);
1306 	if (error != E2BIG) {
1307 		goto out;
1308 	}
1309 	fhsize = FHANDLE_SIZE_FROM_FILEID_SIZE(fidsize);
1310 	fhp = kmem_zalloc(fhsize, KM_SLEEP);
1311 	if (fhp == NULL) {
1312 		error = ENOMEM;
1313 		goto out;
1314 	}
1315 	fhp->fh_fsid = mp->mnt_stat.f_fsidx;
1316 	error = VFS_VPTOFH(vp, &fhp->fh_fid, &fidsize);
1317 	if (error == 0) {
1318 		KASSERT((FHANDLE_SIZE(fhp) == fhsize &&
1319 		    FHANDLE_FILEID(fhp)->fid_len == fidsize));
1320 		*fhpp = fhp;
1321 	} else {
1322 		kmem_free(fhp, fhsize);
1323 	}
1324 out:
1325 	return error;
1326 }
1327 
1328 void
1329 vfs_composefh_free(fhandle_t *fhp)
1330 {
1331 
1332 	vfs__fhfree(fhp);
1333 }
1334 
1335 /*
1336  * vfs_fhtovp: lookup a vnode by a filehandle.
1337  */
1338 
1339 int
1340 vfs_fhtovp(fhandle_t *fhp, struct vnode **vpp)
1341 {
1342 	struct mount *mp;
1343 	int error;
1344 
1345 	*vpp = NULL;
1346 	mp = vfs_getvfs(FHANDLE_FSID(fhp));
1347 	if (mp == NULL) {
1348 		error = ESTALE;
1349 		goto out;
1350 	}
1351 	if (mp->mnt_op->vfs_fhtovp == NULL) {
1352 		error = EOPNOTSUPP;
1353 		goto out;
1354 	}
1355 	error = VFS_FHTOVP(mp, FHANDLE_FILEID(fhp), vpp);
1356 out:
1357 	return error;
1358 }
1359 
1360 /*
1361  * vfs_copyinfh_alloc: allocate and copyin a filehandle, given
1362  * the needed size.
1363  */
1364 
1365 int
1366 vfs_copyinfh_alloc(const void *ufhp, size_t fhsize, fhandle_t **fhpp)
1367 {
1368 	fhandle_t *fhp;
1369 	int error;
1370 
1371 	*fhpp = NULL;
1372 	if (fhsize > FHANDLE_SIZE_MAX) {
1373 		return EINVAL;
1374 	}
1375 	if (fhsize < FHANDLE_SIZE_MIN) {
1376 		return EINVAL;
1377 	}
1378 again:
1379 	fhp = kmem_alloc(fhsize, KM_SLEEP);
1380 	if (fhp == NULL) {
1381 		return ENOMEM;
1382 	}
1383 	error = copyin(ufhp, fhp, fhsize);
1384 	if (error == 0) {
1385 		/* XXX this check shouldn't be here */
1386 		if (FHANDLE_SIZE(fhp) == fhsize) {
1387 			*fhpp = fhp;
1388 			return 0;
1389 		} else if (fhsize == NFSX_V2FH && FHANDLE_SIZE(fhp) < fhsize) {
1390 			/*
1391 			 * a kludge for nfsv2 padded handles.
1392 			 */
1393 			size_t sz;
1394 
1395 			sz = FHANDLE_SIZE(fhp);
1396 			kmem_free(fhp, fhsize);
1397 			fhsize = sz;
1398 			goto again;
1399 		} else {
1400 			/*
1401 			 * userland told us wrong size.
1402 			 */
1403 		    	error = EINVAL;
1404 		}
1405 	}
1406 	kmem_free(fhp, fhsize);
1407 	return error;
1408 }
1409 
1410 void
1411 vfs_copyinfh_free(fhandle_t *fhp)
1412 {
1413 
1414 	vfs__fhfree(fhp);
1415 }
1416 
1417 /*
1418  * Get file handle system call
1419  */
1420 int
1421 sys___getfh30(struct lwp *l, void *v, register_t *retval)
1422 {
1423 	struct sys___getfh30_args /* {
1424 		syscallarg(char *) fname;
1425 		syscallarg(fhandle_t *) fhp;
1426 		syscallarg(size_t *) fh_size;
1427 	} */ *uap = v;
1428 	struct vnode *vp;
1429 	fhandle_t *fh;
1430 	int error;
1431 	struct nameidata nd;
1432 	size_t sz;
1433 	size_t usz;
1434 
1435 	/*
1436 	 * Must be super user
1437 	 */
1438 	error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_FILEHANDLE,
1439 	    0, NULL, NULL, NULL);
1440 	if (error)
1441 		return (error);
1442 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
1443 	    SCARG(uap, fname), l);
1444 	error = namei(&nd);
1445 	if (error)
1446 		return (error);
1447 	vp = nd.ni_vp;
1448 	error = vfs_composefh_alloc(vp, &fh);
1449 	vput(vp);
1450 	if (error != 0) {
1451 		goto out;
1452 	}
1453 	error = copyin(SCARG(uap, fh_size), &usz, sizeof(size_t));
1454 	if (error != 0) {
1455 		goto out;
1456 	}
1457 	sz = FHANDLE_SIZE(fh);
1458 	error = copyout(&sz, SCARG(uap, fh_size), sizeof(size_t));
1459 	if (error != 0) {
1460 		goto out;
1461 	}
1462 	if (usz >= sz) {
1463 		error = copyout(fh, SCARG(uap, fhp), sz);
1464 	} else {
1465 		error = E2BIG;
1466 	}
1467 out:
1468 	vfs_composefh_free(fh);
1469 	return (error);
1470 }
1471 
1472 /*
1473  * Open a file given a file handle.
1474  *
1475  * Check permissions, allocate an open file structure,
1476  * and call the device open routine if any.
1477  */
1478 
1479 int
1480 dofhopen(struct lwp *l, const void *ufhp, size_t fhsize, int oflags,
1481     register_t *retval)
1482 {
1483 	struct filedesc *fdp = l->l_proc->p_fd;
1484 	struct file *fp;
1485 	struct vnode *vp = NULL;
1486 	struct mount *mp;
1487 	kauth_cred_t cred = l->l_cred;
1488 	struct file *nfp;
1489 	int type, indx, error=0;
1490 	struct flock lf;
1491 	struct vattr va;
1492 	fhandle_t *fh;
1493 	int flags;
1494 
1495 	/*
1496 	 * Must be super user
1497 	 */
1498 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_FILEHANDLE,
1499 	    0, NULL, NULL, NULL)))
1500 		return (error);
1501 
1502 	flags = FFLAGS(oflags);
1503 	if ((flags & (FREAD | FWRITE)) == 0)
1504 		return (EINVAL);
1505 	if ((flags & O_CREAT))
1506 		return (EINVAL);
1507 	/* falloc() will use the file descriptor for us */
1508 	if ((error = falloc(l, &nfp, &indx)) != 0)
1509 		return (error);
1510 	fp = nfp;
1511 	error = vfs_copyinfh_alloc(ufhp, fhsize, &fh);
1512 	if (error != 0) {
1513 		goto bad;
1514 	}
1515 	error = vfs_fhtovp(fh, &vp);
1516 	if (error != 0) {
1517 		goto bad;
1518 	}
1519 
1520 	/* Now do an effective vn_open */
1521 
1522 	if (vp->v_type == VSOCK) {
1523 		error = EOPNOTSUPP;
1524 		goto bad;
1525 	}
1526 	if (flags & FREAD) {
1527 		if ((error = VOP_ACCESS(vp, VREAD, cred, l)) != 0)
1528 			goto bad;
1529 	}
1530 	if (flags & (FWRITE | O_TRUNC)) {
1531 		if (vp->v_type == VDIR) {
1532 			error = EISDIR;
1533 			goto bad;
1534 		}
1535 		if ((error = vn_writechk(vp)) != 0 ||
1536 		    (error = VOP_ACCESS(vp, VWRITE, cred, l)) != 0)
1537 			goto bad;
1538 	}
1539 	if (flags & O_TRUNC) {
1540 		if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
1541 			goto bad;
1542 		VOP_UNLOCK(vp, 0);			/* XXX */
1543 		VOP_LEASE(vp, l, cred, LEASE_WRITE);
1544 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);   /* XXX */
1545 		VATTR_NULL(&va);
1546 		va.va_size = 0;
1547 		error = VOP_SETATTR(vp, &va, cred, l);
1548 		vn_finished_write(mp, 0);
1549 		if (error)
1550 			goto bad;
1551 	}
1552 	if ((error = VOP_OPEN(vp, flags, cred, l)) != 0)
1553 		goto bad;
1554 	if (vp->v_type == VREG &&
1555 	    uvn_attach(vp, flags & FWRITE ? VM_PROT_WRITE : 0) == NULL) {
1556 		error = EIO;
1557 		goto bad;
1558 	}
1559 	if (flags & FWRITE)
1560 		vp->v_writecount++;
1561 
1562 	/* done with modified vn_open, now finish what sys_open does. */
1563 
1564 	fp->f_flag = flags & FMASK;
1565 	fp->f_type = DTYPE_VNODE;
1566 	fp->f_ops = &vnops;
1567 	fp->f_data = vp;
1568 	if (flags & (O_EXLOCK | O_SHLOCK)) {
1569 		lf.l_whence = SEEK_SET;
1570 		lf.l_start = 0;
1571 		lf.l_len = 0;
1572 		if (flags & O_EXLOCK)
1573 			lf.l_type = F_WRLCK;
1574 		else
1575 			lf.l_type = F_RDLCK;
1576 		type = F_FLOCK;
1577 		if ((flags & FNONBLOCK) == 0)
1578 			type |= F_WAIT;
1579 		VOP_UNLOCK(vp, 0);
1580 		error = VOP_ADVLOCK(vp, fp, F_SETLK, &lf, type);
1581 		if (error) {
1582 			(void) vn_close(vp, fp->f_flag, fp->f_cred, l);
1583 			FILE_UNUSE(fp, l);
1584 			ffree(fp);
1585 			fdremove(fdp, indx);
1586 			return (error);
1587 		}
1588 		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1589 		fp->f_flag |= FHASLOCK;
1590 	}
1591 	VOP_UNLOCK(vp, 0);
1592 	*retval = indx;
1593 	FILE_SET_MATURE(fp);
1594 	FILE_UNUSE(fp, l);
1595 	vfs_copyinfh_free(fh);
1596 	return (0);
1597 
1598 bad:
1599 	FILE_UNUSE(fp, l);
1600 	ffree(fp);
1601 	fdremove(fdp, indx);
1602 	if (vp != NULL)
1603 		vput(vp);
1604 	vfs_copyinfh_free(fh);
1605 	return (error);
1606 }
1607 
1608 int
1609 sys___fhopen40(struct lwp *l, void *v, register_t *retval)
1610 {
1611 	struct sys___fhopen40_args /* {
1612 		syscallarg(const void *) fhp;
1613 		syscallarg(size_t) fh_size;
1614 		syscallarg(int) flags;
1615 	} */ *uap = v;
1616 
1617 	return dofhopen(l, SCARG(uap, fhp), SCARG(uap, fh_size),
1618 	    SCARG(uap, flags), retval);
1619 }
1620 
1621 int
1622 dofhstat(struct lwp *l, const void *ufhp, size_t fhsize, struct stat *sbp,
1623     register_t *retval)
1624 {
1625 	struct stat sb;
1626 	int error;
1627 	fhandle_t *fh;
1628 	struct vnode *vp;
1629 
1630 	/*
1631 	 * Must be super user
1632 	 */
1633 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_FILEHANDLE,
1634 	    0, NULL, NULL, NULL)))
1635 		return (error);
1636 
1637 	error = vfs_copyinfh_alloc(ufhp, fhsize, &fh);
1638 	if (error != 0) {
1639 		goto bad;
1640 	}
1641 	error = vfs_fhtovp(fh, &vp);
1642 	if (error != 0) {
1643 		goto bad;
1644 	}
1645 	error = vn_stat(vp, &sb, l);
1646 	vput(vp);
1647 	if (error) {
1648 		goto bad;
1649 	}
1650 	error = copyout(&sb, sbp, sizeof(sb));
1651 bad:
1652 	vfs_copyinfh_free(fh);
1653 	return error;
1654 }
1655 
1656 
1657 /* ARGSUSED */
1658 int
1659 sys___fhstat40(struct lwp *l, void *v, register_t *retval)
1660 {
1661 	struct sys___fhstat40_args /* {
1662 		syscallarg(const void *) fhp;
1663 		syscallarg(size_t) fh_size;
1664 		syscallarg(struct stat *) sb;
1665 	} */ *uap = v;
1666 
1667 	return dofhstat(l, SCARG(uap, fhp), SCARG(uap, fh_size), SCARG(uap, sb),
1668 	    retval);
1669 }
1670 
1671 int
1672 dofhstatvfs(struct lwp *l, const void *ufhp, size_t fhsize, struct statvfs *buf,
1673     int flags, register_t *retval)
1674 {
1675 	struct statvfs *sb = NULL;
1676 	fhandle_t *fh;
1677 	struct mount *mp;
1678 	struct vnode *vp;
1679 	int error;
1680 
1681 	/*
1682 	 * Must be super user
1683 	 */
1684 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_FILEHANDLE,
1685 	    0, NULL, NULL, NULL)))
1686 		return error;
1687 
1688 	error = vfs_copyinfh_alloc(ufhp, fhsize, &fh);
1689 	if (error != 0) {
1690 		goto out;
1691 	}
1692 	error = vfs_fhtovp(fh, &vp);
1693 	if (error != 0) {
1694 		goto out;
1695 	}
1696 	mp = vp->v_mount;
1697 	sb = STATVFSBUF_GET();
1698 	if ((error = dostatvfs(mp, sb, l, flags, 1)) != 0) {
1699 		vput(vp);
1700 		goto out;
1701 	}
1702 	vput(vp);
1703 	error = copyout(sb, buf, sizeof(*sb));
1704 out:
1705 	if (sb != NULL) {
1706 		STATVFSBUF_PUT(sb);
1707 	}
1708 	vfs_copyinfh_free(fh);
1709 	return error;
1710 }
1711 
1712 /* ARGSUSED */
1713 int
1714 sys___fhstatvfs140(struct lwp *l, void *v, register_t *retval)
1715 {
1716 	struct sys___fhstatvfs140_args /* {
1717 		syscallarg(const void *) fhp;
1718 		syscallarg(size_t) fh_size;
1719 		syscallarg(struct statvfs *) buf;
1720 		syscallarg(int)	flags;
1721 	} */ *uap = v;
1722 
1723 	return dofhstatvfs(l, SCARG(uap, fhp), SCARG(uap, fh_size),
1724 	    SCARG(uap, buf), SCARG(uap, flags), retval);
1725 }
1726 
1727 /*
1728  * Create a special file.
1729  */
1730 /* ARGSUSED */
1731 int
1732 sys_mknod(struct lwp *l, void *v, register_t *retval)
1733 {
1734 	struct sys_mknod_args /* {
1735 		syscallarg(const char *) path;
1736 		syscallarg(int) mode;
1737 		syscallarg(int) dev;
1738 	} */ *uap = v;
1739 	struct proc *p = l->l_proc;
1740 	struct vnode *vp;
1741 	struct mount *mp;
1742 	struct vattr vattr;
1743 	int error;
1744 	int whiteout = 0;
1745 	struct nameidata nd;
1746 
1747 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MKNOD,
1748 	    0, NULL, NULL, NULL)) != 0)
1749 		return (error);
1750 restart:
1751 	NDINIT(&nd, CREATE, LOCKPARENT, UIO_USERSPACE, SCARG(uap, path), l);
1752 	if ((error = namei(&nd)) != 0)
1753 		return (error);
1754 	vp = nd.ni_vp;
1755 	if (vp != NULL)
1756 		error = EEXIST;
1757 	else {
1758 		VATTR_NULL(&vattr);
1759 		vattr.va_mode =
1760 		    (SCARG(uap, mode) & ALLPERMS) &~ p->p_cwdi->cwdi_cmask;
1761 		vattr.va_rdev = SCARG(uap, dev);
1762 		whiteout = 0;
1763 
1764 		switch (SCARG(uap, mode) & S_IFMT) {
1765 		case S_IFMT:	/* used by badsect to flag bad sectors */
1766 			vattr.va_type = VBAD;
1767 			break;
1768 		case S_IFCHR:
1769 			vattr.va_type = VCHR;
1770 			break;
1771 		case S_IFBLK:
1772 			vattr.va_type = VBLK;
1773 			break;
1774 		case S_IFWHT:
1775 			whiteout = 1;
1776 			break;
1777 		default:
1778 			error = EINVAL;
1779 			break;
1780 		}
1781 	}
1782 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1783 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1784 		if (nd.ni_dvp == vp)
1785 			vrele(nd.ni_dvp);
1786 		else
1787 			vput(nd.ni_dvp);
1788 		if (vp)
1789 			vrele(vp);
1790 		if ((error = vn_start_write(NULL, &mp,
1791 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
1792 			return (error);
1793 		goto restart;
1794 	}
1795 	if (!error) {
1796 		VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
1797 		if (whiteout) {
1798 			error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, CREATE);
1799 			if (error)
1800 				VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1801 			vput(nd.ni_dvp);
1802 		} else {
1803 			error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp,
1804 						&nd.ni_cnd, &vattr);
1805 			if (error == 0)
1806 				vput(nd.ni_vp);
1807 		}
1808 	} else {
1809 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1810 		if (nd.ni_dvp == vp)
1811 			vrele(nd.ni_dvp);
1812 		else
1813 			vput(nd.ni_dvp);
1814 		if (vp)
1815 			vrele(vp);
1816 	}
1817 	vn_finished_write(mp, 0);
1818 	return (error);
1819 }
1820 
1821 /*
1822  * Create a named pipe.
1823  */
1824 /* ARGSUSED */
1825 int
1826 sys_mkfifo(struct lwp *l, void *v, register_t *retval)
1827 {
1828 	struct sys_mkfifo_args /* {
1829 		syscallarg(const char *) path;
1830 		syscallarg(int) mode;
1831 	} */ *uap = v;
1832 	struct proc *p = l->l_proc;
1833 	struct mount *mp;
1834 	struct vattr vattr;
1835 	int error;
1836 	struct nameidata nd;
1837 
1838 restart:
1839 	NDINIT(&nd, CREATE, LOCKPARENT, UIO_USERSPACE, SCARG(uap, path), l);
1840 	if ((error = namei(&nd)) != 0)
1841 		return (error);
1842 	if (nd.ni_vp != NULL) {
1843 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1844 		if (nd.ni_dvp == nd.ni_vp)
1845 			vrele(nd.ni_dvp);
1846 		else
1847 			vput(nd.ni_dvp);
1848 		vrele(nd.ni_vp);
1849 		return (EEXIST);
1850 	}
1851 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1852 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1853 		if (nd.ni_dvp == nd.ni_vp)
1854 			vrele(nd.ni_dvp);
1855 		else
1856 			vput(nd.ni_dvp);
1857 		if (nd.ni_vp)
1858 			vrele(nd.ni_vp);
1859 		if ((error = vn_start_write(NULL, &mp,
1860 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
1861 			return (error);
1862 		goto restart;
1863 	}
1864 	VATTR_NULL(&vattr);
1865 	vattr.va_type = VFIFO;
1866 	vattr.va_mode = (SCARG(uap, mode) & ALLPERMS) &~ p->p_cwdi->cwdi_cmask;
1867 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
1868 	error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
1869 	if (error == 0)
1870 		vput(nd.ni_vp);
1871 	vn_finished_write(mp, 0);
1872 	return (error);
1873 }
1874 
1875 /*
1876  * Make a hard file link.
1877  */
1878 /* ARGSUSED */
1879 int
1880 sys_link(struct lwp *l, void *v, register_t *retval)
1881 {
1882 	struct sys_link_args /* {
1883 		syscallarg(const char *) path;
1884 		syscallarg(const char *) link;
1885 	} */ *uap = v;
1886 	struct vnode *vp;
1887 	struct mount *mp;
1888 	struct nameidata nd;
1889 	int error;
1890 
1891 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
1892 	if ((error = namei(&nd)) != 0)
1893 		return (error);
1894 	vp = nd.ni_vp;
1895 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) {
1896 		vrele(vp);
1897 		return (error);
1898 	}
1899 	NDINIT(&nd, CREATE, LOCKPARENT, UIO_USERSPACE, SCARG(uap, link), l);
1900 	if ((error = namei(&nd)) != 0)
1901 		goto out;
1902 	if (nd.ni_vp) {
1903 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1904 		if (nd.ni_dvp == nd.ni_vp)
1905 			vrele(nd.ni_dvp);
1906 		else
1907 			vput(nd.ni_dvp);
1908 		vrele(nd.ni_vp);
1909 		error = EEXIST;
1910 		goto out;
1911 	}
1912 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
1913 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
1914 	error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd);
1915 out:
1916 	vrele(vp);
1917 	vn_finished_write(mp, 0);
1918 	return (error);
1919 }
1920 
1921 /*
1922  * Make a symbolic link.
1923  */
1924 /* ARGSUSED */
1925 int
1926 sys_symlink(struct lwp *l, void *v, register_t *retval)
1927 {
1928 	struct sys_symlink_args /* {
1929 		syscallarg(const char *) path;
1930 		syscallarg(const char *) link;
1931 	} */ *uap = v;
1932 	struct proc *p = l->l_proc;
1933 	struct mount *mp;
1934 	struct vattr vattr;
1935 	char *path;
1936 	int error;
1937 	struct nameidata nd;
1938 
1939 	path = PNBUF_GET();
1940 	error = copyinstr(SCARG(uap, path), path, MAXPATHLEN, NULL);
1941 	if (error)
1942 		goto out;
1943 restart:
1944 	NDINIT(&nd, CREATE, LOCKPARENT, UIO_USERSPACE, SCARG(uap, link), l);
1945 	if ((error = namei(&nd)) != 0)
1946 		goto out;
1947 	if (nd.ni_vp) {
1948 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1949 		if (nd.ni_dvp == nd.ni_vp)
1950 			vrele(nd.ni_dvp);
1951 		else
1952 			vput(nd.ni_dvp);
1953 		vrele(nd.ni_vp);
1954 		error = EEXIST;
1955 		goto out;
1956 	}
1957 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
1958 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
1959 		if (nd.ni_dvp == nd.ni_vp)
1960 			vrele(nd.ni_dvp);
1961 		else
1962 			vput(nd.ni_dvp);
1963 		if ((error = vn_start_write(NULL, &mp,
1964 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
1965 			return (error);
1966 		goto restart;
1967 	}
1968 	VATTR_NULL(&vattr);
1969 	vattr.va_type = VLNK;
1970 	vattr.va_mode = ACCESSPERMS &~ p->p_cwdi->cwdi_cmask;
1971 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
1972 	error = VOP_SYMLINK(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr, path);
1973 	if (error == 0)
1974 		vput(nd.ni_vp);
1975 	vn_finished_write(mp, 0);
1976 out:
1977 	PNBUF_PUT(path);
1978 	return (error);
1979 }
1980 
1981 /*
1982  * Delete a whiteout from the filesystem.
1983  */
1984 /* ARGSUSED */
1985 int
1986 sys_undelete(struct lwp *l, void *v, register_t *retval)
1987 {
1988 	struct sys_undelete_args /* {
1989 		syscallarg(const char *) path;
1990 	} */ *uap = v;
1991 	int error;
1992 	struct mount *mp;
1993 	struct nameidata nd;
1994 
1995 restart:
1996 	NDINIT(&nd, DELETE, LOCKPARENT|DOWHITEOUT, UIO_USERSPACE,
1997 	    SCARG(uap, path), l);
1998 	error = namei(&nd);
1999 	if (error)
2000 		return (error);
2001 
2002 	if (nd.ni_vp != NULLVP || !(nd.ni_cnd.cn_flags & ISWHITEOUT)) {
2003 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2004 		if (nd.ni_dvp == nd.ni_vp)
2005 			vrele(nd.ni_dvp);
2006 		else
2007 			vput(nd.ni_dvp);
2008 		if (nd.ni_vp)
2009 			vrele(nd.ni_vp);
2010 		return (EEXIST);
2011 	}
2012 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
2013 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2014 		if (nd.ni_dvp == nd.ni_vp)
2015 			vrele(nd.ni_dvp);
2016 		else
2017 			vput(nd.ni_dvp);
2018 		if ((error = vn_start_write(NULL, &mp,
2019 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
2020 			return (error);
2021 		goto restart;
2022 	}
2023 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
2024 	if ((error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, DELETE)) != 0)
2025 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2026 	vput(nd.ni_dvp);
2027 	vn_finished_write(mp, 0);
2028 	return (error);
2029 }
2030 
2031 /*
2032  * Delete a name from the filesystem.
2033  */
2034 /* ARGSUSED */
2035 int
2036 sys_unlink(struct lwp *l, void *v, register_t *retval)
2037 {
2038 	struct sys_unlink_args /* {
2039 		syscallarg(const char *) path;
2040 	} */ *uap = v;
2041 	struct mount *mp;
2042 	struct vnode *vp;
2043 	int error;
2044 	struct nameidata nd;
2045 
2046 restart:
2047 	NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF, UIO_USERSPACE,
2048 	    SCARG(uap, path), l);
2049 	if ((error = namei(&nd)) != 0)
2050 		return (error);
2051 	vp = nd.ni_vp;
2052 
2053 	/*
2054 	 * The root of a mounted filesystem cannot be deleted.
2055 	 */
2056 	if (vp->v_flag & VROOT) {
2057 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2058 		if (nd.ni_dvp == vp)
2059 			vrele(nd.ni_dvp);
2060 		else
2061 			vput(nd.ni_dvp);
2062 		vput(vp);
2063 		error = EBUSY;
2064 		goto out;
2065 	}
2066 
2067 #if NVERIEXEC > 0
2068 	/* Handle remove requests for veriexec entries. */
2069 	if ((error = veriexec_removechk(vp, nd.ni_dirp, l)) != 0) {
2070 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2071 		if (nd.ni_dvp == vp)
2072 			vrele(nd.ni_dvp);
2073 		else
2074 			vput(nd.ni_dvp);
2075 		vput(vp);
2076 		goto out;
2077 	}
2078 #endif /* NVERIEXEC > 0 */
2079 
2080 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
2081 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
2082 		if (nd.ni_dvp == vp)
2083 			vrele(nd.ni_dvp);
2084 		else
2085 			vput(nd.ni_dvp);
2086 		vput(vp);
2087 		if ((error = vn_start_write(NULL, &mp,
2088 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
2089 			return (error);
2090 		goto restart;
2091 	}
2092 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
2093 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
2094 #ifdef FILEASSOC
2095 	(void)fileassoc_file_delete(nd.ni_vp);
2096 #endif /* FILEASSOC */
2097 	error = VOP_REMOVE(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
2098 	vn_finished_write(mp, 0);
2099 out:
2100 	return (error);
2101 }
2102 
2103 /*
2104  * Reposition read/write file offset.
2105  */
2106 int
2107 sys_lseek(struct lwp *l, void *v, register_t *retval)
2108 {
2109 	struct sys_lseek_args /* {
2110 		syscallarg(int) fd;
2111 		syscallarg(int) pad;
2112 		syscallarg(off_t) offset;
2113 		syscallarg(int) whence;
2114 	} */ *uap = v;
2115 	struct proc *p = l->l_proc;
2116 	kauth_cred_t cred = l->l_cred;
2117 	struct filedesc *fdp = p->p_fd;
2118 	struct file *fp;
2119 	struct vnode *vp;
2120 	struct vattr vattr;
2121 	off_t newoff;
2122 	int error;
2123 
2124 	if ((fp = fd_getfile(fdp, SCARG(uap, fd))) == NULL)
2125 		return (EBADF);
2126 
2127 	FILE_USE(fp);
2128 
2129 	vp = (struct vnode *)fp->f_data;
2130 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
2131 		error = ESPIPE;
2132 		goto out;
2133 	}
2134 
2135 	switch (SCARG(uap, whence)) {
2136 	case SEEK_CUR:
2137 		newoff = fp->f_offset + SCARG(uap, offset);
2138 		break;
2139 	case SEEK_END:
2140 		error = VOP_GETATTR(vp, &vattr, cred, l);
2141 		if (error)
2142 			goto out;
2143 		newoff = SCARG(uap, offset) + vattr.va_size;
2144 		break;
2145 	case SEEK_SET:
2146 		newoff = SCARG(uap, offset);
2147 		break;
2148 	default:
2149 		error = EINVAL;
2150 		goto out;
2151 	}
2152 	if ((error = VOP_SEEK(vp, fp->f_offset, newoff, cred)) != 0)
2153 		goto out;
2154 
2155 	*(off_t *)retval = fp->f_offset = newoff;
2156  out:
2157 	FILE_UNUSE(fp, l);
2158 	return (error);
2159 }
2160 
2161 /*
2162  * Positional read system call.
2163  */
2164 int
2165 sys_pread(struct lwp *l, void *v, register_t *retval)
2166 {
2167 	struct sys_pread_args /* {
2168 		syscallarg(int) fd;
2169 		syscallarg(void *) buf;
2170 		syscallarg(size_t) nbyte;
2171 		syscallarg(off_t) offset;
2172 	} */ *uap = v;
2173 	struct proc *p = l->l_proc;
2174 	struct filedesc *fdp = p->p_fd;
2175 	struct file *fp;
2176 	struct vnode *vp;
2177 	off_t offset;
2178 	int error, fd = SCARG(uap, fd);
2179 
2180 	if ((fp = fd_getfile(fdp, fd)) == NULL)
2181 		return (EBADF);
2182 
2183 	if ((fp->f_flag & FREAD) == 0) {
2184 		simple_unlock(&fp->f_slock);
2185 		return (EBADF);
2186 	}
2187 
2188 	FILE_USE(fp);
2189 
2190 	vp = (struct vnode *)fp->f_data;
2191 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
2192 		error = ESPIPE;
2193 		goto out;
2194 	}
2195 
2196 	offset = SCARG(uap, offset);
2197 
2198 	/*
2199 	 * XXX This works because no file systems actually
2200 	 * XXX take any action on the seek operation.
2201 	 */
2202 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
2203 		goto out;
2204 
2205 	/* dofileread() will unuse the descriptor for us */
2206 	return (dofileread(l, fd, fp, SCARG(uap, buf), SCARG(uap, nbyte),
2207 	    &offset, 0, retval));
2208 
2209  out:
2210 	FILE_UNUSE(fp, l);
2211 	return (error);
2212 }
2213 
2214 /*
2215  * Positional scatter read system call.
2216  */
2217 int
2218 sys_preadv(struct lwp *l, void *v, register_t *retval)
2219 {
2220 	struct sys_preadv_args /* {
2221 		syscallarg(int) fd;
2222 		syscallarg(const struct iovec *) iovp;
2223 		syscallarg(int) iovcnt;
2224 		syscallarg(off_t) offset;
2225 	} */ *uap = v;
2226 	struct proc *p = l->l_proc;
2227 	struct filedesc *fdp = p->p_fd;
2228 	struct file *fp;
2229 	struct vnode *vp;
2230 	off_t offset;
2231 	int error, fd = SCARG(uap, fd);
2232 
2233 	if ((fp = fd_getfile(fdp, fd)) == NULL)
2234 		return (EBADF);
2235 
2236 	if ((fp->f_flag & FREAD) == 0) {
2237 		simple_unlock(&fp->f_slock);
2238 		return (EBADF);
2239 	}
2240 
2241 	FILE_USE(fp);
2242 
2243 	vp = (struct vnode *)fp->f_data;
2244 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
2245 		error = ESPIPE;
2246 		goto out;
2247 	}
2248 
2249 	offset = SCARG(uap, offset);
2250 
2251 	/*
2252 	 * XXX This works because no file systems actually
2253 	 * XXX take any action on the seek operation.
2254 	 */
2255 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
2256 		goto out;
2257 
2258 	/* dofilereadv() will unuse the descriptor for us */
2259 	return (dofilereadv(l, fd, fp, SCARG(uap, iovp), SCARG(uap, iovcnt),
2260 	    &offset, 0, retval));
2261 
2262  out:
2263 	FILE_UNUSE(fp, l);
2264 	return (error);
2265 }
2266 
2267 /*
2268  * Positional write system call.
2269  */
2270 int
2271 sys_pwrite(struct lwp *l, void *v, register_t *retval)
2272 {
2273 	struct sys_pwrite_args /* {
2274 		syscallarg(int) fd;
2275 		syscallarg(const void *) buf;
2276 		syscallarg(size_t) nbyte;
2277 		syscallarg(off_t) offset;
2278 	} */ *uap = v;
2279 	struct proc *p = l->l_proc;
2280 	struct filedesc *fdp = p->p_fd;
2281 	struct file *fp;
2282 	struct vnode *vp;
2283 	off_t offset;
2284 	int error, fd = SCARG(uap, fd);
2285 
2286 	if ((fp = fd_getfile(fdp, fd)) == NULL)
2287 		return (EBADF);
2288 
2289 	if ((fp->f_flag & FWRITE) == 0) {
2290 		simple_unlock(&fp->f_slock);
2291 		return (EBADF);
2292 	}
2293 
2294 	FILE_USE(fp);
2295 
2296 	vp = (struct vnode *)fp->f_data;
2297 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
2298 		error = ESPIPE;
2299 		goto out;
2300 	}
2301 
2302 	offset = SCARG(uap, offset);
2303 
2304 	/*
2305 	 * XXX This works because no file systems actually
2306 	 * XXX take any action on the seek operation.
2307 	 */
2308 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
2309 		goto out;
2310 
2311 	/* dofilewrite() will unuse the descriptor for us */
2312 	return (dofilewrite(l, fd, fp, SCARG(uap, buf), SCARG(uap, nbyte),
2313 	    &offset, 0, retval));
2314 
2315  out:
2316 	FILE_UNUSE(fp, l);
2317 	return (error);
2318 }
2319 
2320 /*
2321  * Positional gather write system call.
2322  */
2323 int
2324 sys_pwritev(struct lwp *l, void *v, register_t *retval)
2325 {
2326 	struct sys_pwritev_args /* {
2327 		syscallarg(int) fd;
2328 		syscallarg(const struct iovec *) iovp;
2329 		syscallarg(int) iovcnt;
2330 		syscallarg(off_t) offset;
2331 	} */ *uap = v;
2332 	struct proc *p = l->l_proc;
2333 	struct filedesc *fdp = p->p_fd;
2334 	struct file *fp;
2335 	struct vnode *vp;
2336 	off_t offset;
2337 	int error, fd = SCARG(uap, fd);
2338 
2339 	if ((fp = fd_getfile(fdp, fd)) == NULL)
2340 		return (EBADF);
2341 
2342 	if ((fp->f_flag & FWRITE) == 0) {
2343 		simple_unlock(&fp->f_slock);
2344 		return (EBADF);
2345 	}
2346 
2347 	FILE_USE(fp);
2348 
2349 	vp = (struct vnode *)fp->f_data;
2350 	if (fp->f_type != DTYPE_VNODE || vp->v_type == VFIFO) {
2351 		error = ESPIPE;
2352 		goto out;
2353 	}
2354 
2355 	offset = SCARG(uap, offset);
2356 
2357 	/*
2358 	 * XXX This works because no file systems actually
2359 	 * XXX take any action on the seek operation.
2360 	 */
2361 	if ((error = VOP_SEEK(vp, fp->f_offset, offset, fp->f_cred)) != 0)
2362 		goto out;
2363 
2364 	/* dofilewritev() will unuse the descriptor for us */
2365 	return (dofilewritev(l, fd, fp, SCARG(uap, iovp), SCARG(uap, iovcnt),
2366 	    &offset, 0, retval));
2367 
2368  out:
2369 	FILE_UNUSE(fp, l);
2370 	return (error);
2371 }
2372 
2373 /*
2374  * Check access permissions.
2375  */
2376 int
2377 sys_access(struct lwp *l, void *v, register_t *retval)
2378 {
2379 	struct sys_access_args /* {
2380 		syscallarg(const char *) path;
2381 		syscallarg(int) flags;
2382 	} */ *uap = v;
2383 	kauth_cred_t cred;
2384 	struct vnode *vp;
2385 	int error, flags;
2386 	struct nameidata nd;
2387 
2388 	cred = kauth_cred_dup(l->l_cred);
2389 	kauth_cred_seteuid(cred, kauth_cred_getuid(l->l_cred));
2390 	kauth_cred_setegid(cred, kauth_cred_getgid(l->l_cred));
2391 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
2392 	    SCARG(uap, path), l);
2393 	/* Override default credentials */
2394 	nd.ni_cnd.cn_cred = cred;
2395 	if ((error = namei(&nd)) != 0)
2396 		goto out;
2397 	vp = nd.ni_vp;
2398 
2399 	/* Flags == 0 means only check for existence. */
2400 	if (SCARG(uap, flags)) {
2401 		flags = 0;
2402 		if (SCARG(uap, flags) & R_OK)
2403 			flags |= VREAD;
2404 		if (SCARG(uap, flags) & W_OK)
2405 			flags |= VWRITE;
2406 		if (SCARG(uap, flags) & X_OK)
2407 			flags |= VEXEC;
2408 
2409 		error = VOP_ACCESS(vp, flags, cred, l);
2410 		if (!error && (flags & VWRITE))
2411 			error = vn_writechk(vp);
2412 	}
2413 	vput(vp);
2414 out:
2415 	kauth_cred_free(cred);
2416 	return (error);
2417 }
2418 
2419 /*
2420  * Get file status; this version follows links.
2421  */
2422 /* ARGSUSED */
2423 int
2424 sys___stat30(struct lwp *l, void *v, register_t *retval)
2425 {
2426 	struct sys___stat30_args /* {
2427 		syscallarg(const char *) path;
2428 		syscallarg(struct stat *) ub;
2429 	} */ *uap = v;
2430 	struct stat sb;
2431 	int error;
2432 	struct nameidata nd;
2433 
2434 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
2435 	    SCARG(uap, path), l);
2436 	if ((error = namei(&nd)) != 0)
2437 		return (error);
2438 	error = vn_stat(nd.ni_vp, &sb, l);
2439 	vput(nd.ni_vp);
2440 	if (error)
2441 		return (error);
2442 	error = copyout(&sb, SCARG(uap, ub), sizeof(sb));
2443 	return (error);
2444 }
2445 
2446 /*
2447  * Get file status; this version does not follow links.
2448  */
2449 /* ARGSUSED */
2450 int
2451 sys___lstat30(struct lwp *l, void *v, register_t *retval)
2452 {
2453 	struct sys___lstat30_args /* {
2454 		syscallarg(const char *) path;
2455 		syscallarg(struct stat *) ub;
2456 	} */ *uap = v;
2457 	struct stat sb;
2458 	int error;
2459 	struct nameidata nd;
2460 
2461 	NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF, UIO_USERSPACE,
2462 	    SCARG(uap, path), l);
2463 	if ((error = namei(&nd)) != 0)
2464 		return (error);
2465 	error = vn_stat(nd.ni_vp, &sb, l);
2466 	vput(nd.ni_vp);
2467 	if (error)
2468 		return (error);
2469 	error = copyout(&sb, SCARG(uap, ub), sizeof(sb));
2470 	return (error);
2471 }
2472 
2473 /*
2474  * Get configurable pathname variables.
2475  */
2476 /* ARGSUSED */
2477 int
2478 sys_pathconf(struct lwp *l, void *v, register_t *retval)
2479 {
2480 	struct sys_pathconf_args /* {
2481 		syscallarg(const char *) path;
2482 		syscallarg(int) name;
2483 	} */ *uap = v;
2484 	int error;
2485 	struct nameidata nd;
2486 
2487 	NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF, UIO_USERSPACE,
2488 	    SCARG(uap, path), l);
2489 	if ((error = namei(&nd)) != 0)
2490 		return (error);
2491 	error = VOP_PATHCONF(nd.ni_vp, SCARG(uap, name), retval);
2492 	vput(nd.ni_vp);
2493 	return (error);
2494 }
2495 
2496 /*
2497  * Return target name of a symbolic link.
2498  */
2499 /* ARGSUSED */
2500 int
2501 sys_readlink(struct lwp *l, void *v, register_t *retval)
2502 {
2503 	struct sys_readlink_args /* {
2504 		syscallarg(const char *) path;
2505 		syscallarg(char *) buf;
2506 		syscallarg(size_t) count;
2507 	} */ *uap = v;
2508 	struct vnode *vp;
2509 	struct iovec aiov;
2510 	struct uio auio;
2511 	int error;
2512 	struct nameidata nd;
2513 
2514 	NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF, UIO_USERSPACE,
2515 	    SCARG(uap, path), l);
2516 	if ((error = namei(&nd)) != 0)
2517 		return (error);
2518 	vp = nd.ni_vp;
2519 	if (vp->v_type != VLNK)
2520 		error = EINVAL;
2521 	else if (!(vp->v_mount->mnt_flag & MNT_SYMPERM) ||
2522 	    (error = VOP_ACCESS(vp, VREAD, l->l_cred, l)) == 0) {
2523 		aiov.iov_base = SCARG(uap, buf);
2524 		aiov.iov_len = SCARG(uap, count);
2525 		auio.uio_iov = &aiov;
2526 		auio.uio_iovcnt = 1;
2527 		auio.uio_offset = 0;
2528 		auio.uio_rw = UIO_READ;
2529 		KASSERT(l == curlwp);
2530 		auio.uio_vmspace = l->l_proc->p_vmspace;
2531 		auio.uio_resid = SCARG(uap, count);
2532 		error = VOP_READLINK(vp, &auio, l->l_cred);
2533 	}
2534 	vput(vp);
2535 	*retval = SCARG(uap, count) - auio.uio_resid;
2536 	return (error);
2537 }
2538 
2539 /*
2540  * Change flags of a file given a path name.
2541  */
2542 /* ARGSUSED */
2543 int
2544 sys_chflags(struct lwp *l, void *v, register_t *retval)
2545 {
2546 	struct sys_chflags_args /* {
2547 		syscallarg(const char *) path;
2548 		syscallarg(u_long) flags;
2549 	} */ *uap = v;
2550 	struct vnode *vp;
2551 	int error;
2552 	struct nameidata nd;
2553 
2554 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2555 	if ((error = namei(&nd)) != 0)
2556 		return (error);
2557 	vp = nd.ni_vp;
2558 	error = change_flags(vp, SCARG(uap, flags), l);
2559 	vput(vp);
2560 	return (error);
2561 }
2562 
2563 /*
2564  * Change flags of a file given a file descriptor.
2565  */
2566 /* ARGSUSED */
2567 int
2568 sys_fchflags(struct lwp *l, void *v, register_t *retval)
2569 {
2570 	struct sys_fchflags_args /* {
2571 		syscallarg(int) fd;
2572 		syscallarg(u_long) flags;
2573 	} */ *uap = v;
2574 	struct proc *p = l->l_proc;
2575 	struct vnode *vp;
2576 	struct file *fp;
2577 	int error;
2578 
2579 	/* getvnode() will use the descriptor for us */
2580 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
2581 		return (error);
2582 	vp = (struct vnode *)fp->f_data;
2583 	error = change_flags(vp, SCARG(uap, flags), l);
2584 	VOP_UNLOCK(vp, 0);
2585 	FILE_UNUSE(fp, l);
2586 	return (error);
2587 }
2588 
2589 /*
2590  * Change flags of a file given a path name; this version does
2591  * not follow links.
2592  */
2593 int
2594 sys_lchflags(struct lwp *l, void *v, register_t *retval)
2595 {
2596 	struct sys_lchflags_args /* {
2597 		syscallarg(const char *) path;
2598 		syscallarg(u_long) flags;
2599 	} */ *uap = v;
2600 	struct vnode *vp;
2601 	int error;
2602 	struct nameidata nd;
2603 
2604 	NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2605 	if ((error = namei(&nd)) != 0)
2606 		return (error);
2607 	vp = nd.ni_vp;
2608 	error = change_flags(vp, SCARG(uap, flags), l);
2609 	vput(vp);
2610 	return (error);
2611 }
2612 
2613 /*
2614  * Common routine to change flags of a file.
2615  */
2616 int
2617 change_flags(struct vnode *vp, u_long flags, struct lwp *l)
2618 {
2619 	struct mount *mp;
2620 	struct vattr vattr;
2621 	int error;
2622 
2623 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
2624 		return (error);
2625 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
2626 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2627 	/*
2628 	 * Non-superusers cannot change the flags on devices, even if they
2629 	 * own them.
2630 	 */
2631 	if (kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER,
2632 	    &l->l_acflag) != 0) {
2633 		if ((error = VOP_GETATTR(vp, &vattr, l->l_cred, l)) != 0)
2634 			goto out;
2635 		if (vattr.va_type == VCHR || vattr.va_type == VBLK) {
2636 			error = EINVAL;
2637 			goto out;
2638 		}
2639 	}
2640 	VATTR_NULL(&vattr);
2641 	vattr.va_flags = flags;
2642 	error = VOP_SETATTR(vp, &vattr, l->l_cred, l);
2643 out:
2644 	vn_finished_write(mp, 0);
2645 	return (error);
2646 }
2647 
2648 /*
2649  * Change mode of a file given path name; this version follows links.
2650  */
2651 /* ARGSUSED */
2652 int
2653 sys_chmod(struct lwp *l, void *v, register_t *retval)
2654 {
2655 	struct sys_chmod_args /* {
2656 		syscallarg(const char *) path;
2657 		syscallarg(int) mode;
2658 	} */ *uap = v;
2659 	int error;
2660 	struct nameidata nd;
2661 
2662 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2663 	if ((error = namei(&nd)) != 0)
2664 		return (error);
2665 
2666 	error = change_mode(nd.ni_vp, SCARG(uap, mode), l);
2667 
2668 	vrele(nd.ni_vp);
2669 	return (error);
2670 }
2671 
2672 /*
2673  * Change mode of a file given a file descriptor.
2674  */
2675 /* ARGSUSED */
2676 int
2677 sys_fchmod(struct lwp *l, void *v, register_t *retval)
2678 {
2679 	struct sys_fchmod_args /* {
2680 		syscallarg(int) fd;
2681 		syscallarg(int) mode;
2682 	} */ *uap = v;
2683 	struct proc *p = l->l_proc;
2684 	struct file *fp;
2685 	int error;
2686 
2687 	/* getvnode() will use the descriptor for us */
2688 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
2689 		return (error);
2690 
2691 	error = change_mode((struct vnode *)fp->f_data, SCARG(uap, mode), l);
2692 	FILE_UNUSE(fp, l);
2693 	return (error);
2694 }
2695 
2696 /*
2697  * Change mode of a file given path name; this version does not follow links.
2698  */
2699 /* ARGSUSED */
2700 int
2701 sys_lchmod(struct lwp *l, void *v, register_t *retval)
2702 {
2703 	struct sys_lchmod_args /* {
2704 		syscallarg(const char *) path;
2705 		syscallarg(int) mode;
2706 	} */ *uap = v;
2707 	int error;
2708 	struct nameidata nd;
2709 
2710 	NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2711 	if ((error = namei(&nd)) != 0)
2712 		return (error);
2713 
2714 	error = change_mode(nd.ni_vp, SCARG(uap, mode), l);
2715 
2716 	vrele(nd.ni_vp);
2717 	return (error);
2718 }
2719 
2720 /*
2721  * Common routine to set mode given a vnode.
2722  */
2723 static int
2724 change_mode(struct vnode *vp, int mode, struct lwp *l)
2725 {
2726 	struct mount *mp;
2727 	struct vattr vattr;
2728 	int error;
2729 
2730 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
2731 		return (error);
2732 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
2733 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2734 	VATTR_NULL(&vattr);
2735 	vattr.va_mode = mode & ALLPERMS;
2736 	error = VOP_SETATTR(vp, &vattr, l->l_cred, l);
2737 	VOP_UNLOCK(vp, 0);
2738 	vn_finished_write(mp, 0);
2739 	return (error);
2740 }
2741 
2742 /*
2743  * Set ownership given a path name; this version follows links.
2744  */
2745 /* ARGSUSED */
2746 int
2747 sys_chown(struct lwp *l, void *v, register_t *retval)
2748 {
2749 	struct sys_chown_args /* {
2750 		syscallarg(const char *) path;
2751 		syscallarg(uid_t) uid;
2752 		syscallarg(gid_t) gid;
2753 	} */ *uap = v;
2754 	int error;
2755 	struct nameidata nd;
2756 
2757 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2758 	if ((error = namei(&nd)) != 0)
2759 		return (error);
2760 
2761 	error = change_owner(nd.ni_vp, SCARG(uap, uid), SCARG(uap, gid), l, 0);
2762 
2763 	vrele(nd.ni_vp);
2764 	return (error);
2765 }
2766 
2767 /*
2768  * Set ownership given a path name; this version follows links.
2769  * Provides POSIX semantics.
2770  */
2771 /* ARGSUSED */
2772 int
2773 sys___posix_chown(struct lwp *l, void *v, register_t *retval)
2774 {
2775 	struct sys_chown_args /* {
2776 		syscallarg(const char *) path;
2777 		syscallarg(uid_t) uid;
2778 		syscallarg(gid_t) gid;
2779 	} */ *uap = v;
2780 	int error;
2781 	struct nameidata nd;
2782 
2783 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2784 	if ((error = namei(&nd)) != 0)
2785 		return (error);
2786 
2787 	error = change_owner(nd.ni_vp, SCARG(uap, uid), SCARG(uap, gid), l, 1);
2788 
2789 	vrele(nd.ni_vp);
2790 	return (error);
2791 }
2792 
2793 /*
2794  * Set ownership given a file descriptor.
2795  */
2796 /* ARGSUSED */
2797 int
2798 sys_fchown(struct lwp *l, void *v, register_t *retval)
2799 {
2800 	struct sys_fchown_args /* {
2801 		syscallarg(int) fd;
2802 		syscallarg(uid_t) uid;
2803 		syscallarg(gid_t) gid;
2804 	} */ *uap = v;
2805 	struct proc *p = l->l_proc;
2806 	int error;
2807 	struct file *fp;
2808 
2809 	/* getvnode() will use the descriptor for us */
2810 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
2811 		return (error);
2812 
2813 	error = change_owner((struct vnode *)fp->f_data, SCARG(uap, uid),
2814 	    SCARG(uap, gid), l, 0);
2815 	FILE_UNUSE(fp, l);
2816 	return (error);
2817 }
2818 
2819 /*
2820  * Set ownership given a file descriptor, providing POSIX/XPG semantics.
2821  */
2822 /* ARGSUSED */
2823 int
2824 sys___posix_fchown(struct lwp *l, void *v, register_t *retval)
2825 {
2826 	struct sys_fchown_args /* {
2827 		syscallarg(int) fd;
2828 		syscallarg(uid_t) uid;
2829 		syscallarg(gid_t) gid;
2830 	} */ *uap = v;
2831 	struct proc *p = l->l_proc;
2832 	int error;
2833 	struct file *fp;
2834 
2835 	/* getvnode() will use the descriptor for us */
2836 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
2837 		return (error);
2838 
2839 	error = change_owner((struct vnode *)fp->f_data, SCARG(uap, uid),
2840 	    SCARG(uap, gid), l, 1);
2841 	FILE_UNUSE(fp, l);
2842 	return (error);
2843 }
2844 
2845 /*
2846  * Set ownership given a path name; this version does not follow links.
2847  */
2848 /* ARGSUSED */
2849 int
2850 sys_lchown(struct lwp *l, void *v, register_t *retval)
2851 {
2852 	struct sys_lchown_args /* {
2853 		syscallarg(const char *) path;
2854 		syscallarg(uid_t) uid;
2855 		syscallarg(gid_t) gid;
2856 	} */ *uap = v;
2857 	int error;
2858 	struct nameidata nd;
2859 
2860 	NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2861 	if ((error = namei(&nd)) != 0)
2862 		return (error);
2863 
2864 	error = change_owner(nd.ni_vp, SCARG(uap, uid), SCARG(uap, gid), l, 0);
2865 
2866 	vrele(nd.ni_vp);
2867 	return (error);
2868 }
2869 
2870 /*
2871  * Set ownership given a path name; this version does not follow links.
2872  * Provides POSIX/XPG semantics.
2873  */
2874 /* ARGSUSED */
2875 int
2876 sys___posix_lchown(struct lwp *l, void *v, register_t *retval)
2877 {
2878 	struct sys_lchown_args /* {
2879 		syscallarg(const char *) path;
2880 		syscallarg(uid_t) uid;
2881 		syscallarg(gid_t) gid;
2882 	} */ *uap = v;
2883 	int error;
2884 	struct nameidata nd;
2885 
2886 	NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2887 	if ((error = namei(&nd)) != 0)
2888 		return (error);
2889 
2890 	error = change_owner(nd.ni_vp, SCARG(uap, uid), SCARG(uap, gid), l, 1);
2891 
2892 	vrele(nd.ni_vp);
2893 	return (error);
2894 }
2895 
2896 /*
2897  * Common routine to set ownership given a vnode.
2898  */
2899 static int
2900 change_owner(struct vnode *vp, uid_t uid, gid_t gid, struct lwp *l,
2901     int posix_semantics)
2902 {
2903 	struct mount *mp;
2904 	struct vattr vattr;
2905 	mode_t newmode;
2906 	int error;
2907 
2908 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
2909 		return (error);
2910 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
2911 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2912 	if ((error = VOP_GETATTR(vp, &vattr, l->l_cred, l)) != 0)
2913 		goto out;
2914 
2915 #define CHANGED(x) ((int)(x) != -1)
2916 	newmode = vattr.va_mode;
2917 	if (posix_semantics) {
2918 		/*
2919 		 * POSIX/XPG semantics: if the caller is not the super-user,
2920 		 * clear set-user-id and set-group-id bits.  Both POSIX and
2921 		 * the XPG consider the behaviour for calls by the super-user
2922 		 * implementation-defined; we leave the set-user-id and set-
2923 		 * group-id settings intact in that case.
2924 		 */
2925 		if (kauth_authorize_generic(l->l_cred, KAUTH_GENERIC_ISSUSER,
2926 				      NULL) != 0)
2927 			newmode &= ~(S_ISUID | S_ISGID);
2928 	} else {
2929 		/*
2930 		 * NetBSD semantics: when changing owner and/or group,
2931 		 * clear the respective bit(s).
2932 		 */
2933 		if (CHANGED(uid))
2934 			newmode &= ~S_ISUID;
2935 		if (CHANGED(gid))
2936 			newmode &= ~S_ISGID;
2937 	}
2938 	/* Update va_mode iff altered. */
2939 	if (vattr.va_mode == newmode)
2940 		newmode = VNOVAL;
2941 
2942 	VATTR_NULL(&vattr);
2943 	vattr.va_uid = CHANGED(uid) ? uid : (uid_t)VNOVAL;
2944 	vattr.va_gid = CHANGED(gid) ? gid : (gid_t)VNOVAL;
2945 	vattr.va_mode = newmode;
2946 	error = VOP_SETATTR(vp, &vattr, l->l_cred, l);
2947 #undef CHANGED
2948 
2949 out:
2950 	VOP_UNLOCK(vp, 0);
2951 	vn_finished_write(mp, 0);
2952 	return (error);
2953 }
2954 
2955 /*
2956  * Set the access and modification times given a path name; this
2957  * version follows links.
2958  */
2959 /* ARGSUSED */
2960 int
2961 sys_utimes(struct lwp *l, void *v, register_t *retval)
2962 {
2963 	struct sys_utimes_args /* {
2964 		syscallarg(const char *) path;
2965 		syscallarg(const struct timeval *) tptr;
2966 	} */ *uap = v;
2967 	int error;
2968 	struct nameidata nd;
2969 
2970 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
2971 	if ((error = namei(&nd)) != 0)
2972 		return (error);
2973 
2974 	error = change_utimes(nd.ni_vp, SCARG(uap, tptr), l);
2975 
2976 	vrele(nd.ni_vp);
2977 	return (error);
2978 }
2979 
2980 /*
2981  * Set the access and modification times given a file descriptor.
2982  */
2983 /* ARGSUSED */
2984 int
2985 sys_futimes(struct lwp *l, void *v, register_t *retval)
2986 {
2987 	struct sys_futimes_args /* {
2988 		syscallarg(int) fd;
2989 		syscallarg(const struct timeval *) tptr;
2990 	} */ *uap = v;
2991 	struct proc *p = l->l_proc;
2992 	int error;
2993 	struct file *fp;
2994 
2995 	/* getvnode() will use the descriptor for us */
2996 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
2997 		return (error);
2998 
2999 	error = change_utimes((struct vnode *)fp->f_data, SCARG(uap, tptr), l);
3000 	FILE_UNUSE(fp, l);
3001 	return (error);
3002 }
3003 
3004 /*
3005  * Set the access and modification times given a path name; this
3006  * version does not follow links.
3007  */
3008 /* ARGSUSED */
3009 int
3010 sys_lutimes(struct lwp *l, void *v, register_t *retval)
3011 {
3012 	struct sys_lutimes_args /* {
3013 		syscallarg(const char *) path;
3014 		syscallarg(const struct timeval *) tptr;
3015 	} */ *uap = v;
3016 	int error;
3017 	struct nameidata nd;
3018 
3019 	NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
3020 	if ((error = namei(&nd)) != 0)
3021 		return (error);
3022 
3023 	error = change_utimes(nd.ni_vp, SCARG(uap, tptr), l);
3024 
3025 	vrele(nd.ni_vp);
3026 	return (error);
3027 }
3028 
3029 /*
3030  * Common routine to set access and modification times given a vnode.
3031  */
3032 static int
3033 change_utimes(struct vnode *vp, const struct timeval *tptr, struct lwp *l)
3034 {
3035 	struct mount *mp;
3036 	struct vattr vattr;
3037 	int error;
3038 
3039 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
3040 		return (error);
3041 	VATTR_NULL(&vattr);
3042 	if (tptr == NULL) {
3043 		nanotime(&vattr.va_atime);
3044 		vattr.va_mtime = vattr.va_atime;
3045 		vattr.va_vaflags |= VA_UTIMES_NULL;
3046 	} else {
3047 		struct timeval tv[2];
3048 
3049 		error = copyin(tptr, tv, sizeof(tv));
3050 		if (error)
3051 			goto out;
3052 		TIMEVAL_TO_TIMESPEC(&tv[0], &vattr.va_atime);
3053 		TIMEVAL_TO_TIMESPEC(&tv[1], &vattr.va_mtime);
3054 	}
3055 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
3056 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3057 	error = VOP_SETATTR(vp, &vattr, l->l_cred, l);
3058 	VOP_UNLOCK(vp, 0);
3059 out:
3060 	vn_finished_write(mp, 0);
3061 	return (error);
3062 }
3063 
3064 /*
3065  * Truncate a file given its path name.
3066  */
3067 /* ARGSUSED */
3068 int
3069 sys_truncate(struct lwp *l, void *v, register_t *retval)
3070 {
3071 	struct sys_truncate_args /* {
3072 		syscallarg(const char *) path;
3073 		syscallarg(int) pad;
3074 		syscallarg(off_t) length;
3075 	} */ *uap = v;
3076 	struct vnode *vp;
3077 	struct mount *mp;
3078 	struct vattr vattr;
3079 	int error;
3080 	struct nameidata nd;
3081 
3082 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
3083 	if ((error = namei(&nd)) != 0)
3084 		return (error);
3085 	vp = nd.ni_vp;
3086 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) {
3087 		vrele(vp);
3088 		return (error);
3089 	}
3090 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
3091 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3092 	if (vp->v_type == VDIR)
3093 		error = EISDIR;
3094 	else if ((error = vn_writechk(vp)) == 0 &&
3095 	    (error = VOP_ACCESS(vp, VWRITE, l->l_cred, l)) == 0) {
3096 		VATTR_NULL(&vattr);
3097 		vattr.va_size = SCARG(uap, length);
3098 		error = VOP_SETATTR(vp, &vattr, l->l_cred, l);
3099 	}
3100 	vput(vp);
3101 	vn_finished_write(mp, 0);
3102 	return (error);
3103 }
3104 
3105 /*
3106  * Truncate a file given a file descriptor.
3107  */
3108 /* ARGSUSED */
3109 int
3110 sys_ftruncate(struct lwp *l, void *v, register_t *retval)
3111 {
3112 	struct sys_ftruncate_args /* {
3113 		syscallarg(int) fd;
3114 		syscallarg(int) pad;
3115 		syscallarg(off_t) length;
3116 	} */ *uap = v;
3117 	struct proc *p = l->l_proc;
3118 	struct mount *mp;
3119 	struct vattr vattr;
3120 	struct vnode *vp;
3121 	struct file *fp;
3122 	int error;
3123 
3124 	/* getvnode() will use the descriptor for us */
3125 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
3126 		return (error);
3127 	if ((fp->f_flag & FWRITE) == 0) {
3128 		error = EINVAL;
3129 		goto out;
3130 	}
3131 	vp = (struct vnode *)fp->f_data;
3132 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) {
3133 		FILE_UNUSE(fp, l);
3134 		return (error);
3135 	}
3136 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
3137 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3138 	if (vp->v_type == VDIR)
3139 		error = EISDIR;
3140 	else if ((error = vn_writechk(vp)) == 0) {
3141 		VATTR_NULL(&vattr);
3142 		vattr.va_size = SCARG(uap, length);
3143 		error = VOP_SETATTR(vp, &vattr, fp->f_cred, l);
3144 	}
3145 	VOP_UNLOCK(vp, 0);
3146 	vn_finished_write(mp, 0);
3147  out:
3148 	FILE_UNUSE(fp, l);
3149 	return (error);
3150 }
3151 
3152 /*
3153  * Sync an open file.
3154  */
3155 /* ARGSUSED */
3156 int
3157 sys_fsync(struct lwp *l, void *v, register_t *retval)
3158 {
3159 	struct sys_fsync_args /* {
3160 		syscallarg(int) fd;
3161 	} */ *uap = v;
3162 	struct proc *p = l->l_proc;
3163 	struct vnode *vp;
3164 	struct mount *mp;
3165 	struct file *fp;
3166 	int error;
3167 
3168 	/* getvnode() will use the descriptor for us */
3169 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
3170 		return (error);
3171 	vp = (struct vnode *)fp->f_data;
3172 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) {
3173 		FILE_UNUSE(fp, l);
3174 		return (error);
3175 	}
3176 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3177 	error = VOP_FSYNC(vp, fp->f_cred, FSYNC_WAIT, 0, 0, l);
3178 	if (error == 0 && bioops.io_fsync != NULL &&
3179 	    vp->v_mount && (vp->v_mount->mnt_flag & MNT_SOFTDEP))
3180 		(*bioops.io_fsync)(vp, 0);
3181 	VOP_UNLOCK(vp, 0);
3182 	vn_finished_write(mp, 0);
3183 	FILE_UNUSE(fp, l);
3184 	return (error);
3185 }
3186 
3187 /*
3188  * Sync a range of file data.  API modeled after that found in AIX.
3189  *
3190  * FDATASYNC indicates that we need only save enough metadata to be able
3191  * to re-read the written data.  Note we duplicate AIX's requirement that
3192  * the file be open for writing.
3193  */
3194 /* ARGSUSED */
3195 int
3196 sys_fsync_range(struct lwp *l, void *v, register_t *retval)
3197 {
3198 	struct sys_fsync_range_args /* {
3199 		syscallarg(int) fd;
3200 		syscallarg(int) flags;
3201 		syscallarg(off_t) start;
3202 		syscallarg(off_t) length;
3203 	} */ *uap = v;
3204 	struct proc *p = l->l_proc;
3205 	struct vnode *vp;
3206 	struct file *fp;
3207 	int flags, nflags;
3208 	off_t s, e, len;
3209 	int error;
3210 
3211 	/* getvnode() will use the descriptor for us */
3212 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
3213 		return (error);
3214 
3215 	if ((fp->f_flag & FWRITE) == 0) {
3216 		FILE_UNUSE(fp, l);
3217 		return (EBADF);
3218 	}
3219 
3220 	flags = SCARG(uap, flags);
3221 	if (((flags & (FDATASYNC | FFILESYNC)) == 0) ||
3222 	    ((~flags & (FDATASYNC | FFILESYNC)) == 0)) {
3223 		return (EINVAL);
3224 	}
3225 	/* Now set up the flags for value(s) to pass to VOP_FSYNC() */
3226 	if (flags & FDATASYNC)
3227 		nflags = FSYNC_DATAONLY | FSYNC_WAIT;
3228 	else
3229 		nflags = FSYNC_WAIT;
3230 	if (flags & FDISKSYNC)
3231 		nflags |= FSYNC_CACHE;
3232 
3233 	len = SCARG(uap, length);
3234 	/* If length == 0, we do the whole file, and s = l = 0 will do that */
3235 	if (len) {
3236 		s = SCARG(uap, start);
3237 		e = s + len;
3238 		if (e < s) {
3239 			FILE_UNUSE(fp, l);
3240 			return (EINVAL);
3241 		}
3242 	} else {
3243 		e = 0;
3244 		s = 0;
3245 	}
3246 
3247 	vp = (struct vnode *)fp->f_data;
3248 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3249 	error = VOP_FSYNC(vp, fp->f_cred, nflags, s, e, l);
3250 
3251 	if (error == 0 && bioops.io_fsync != NULL &&
3252 	    vp->v_mount && (vp->v_mount->mnt_flag & MNT_SOFTDEP))
3253 		(*bioops.io_fsync)(vp, nflags);
3254 
3255 	VOP_UNLOCK(vp, 0);
3256 	FILE_UNUSE(fp, l);
3257 	return (error);
3258 }
3259 
3260 /*
3261  * Sync the data of an open file.
3262  */
3263 /* ARGSUSED */
3264 int
3265 sys_fdatasync(struct lwp *l, void *v, register_t *retval)
3266 {
3267 	struct sys_fdatasync_args /* {
3268 		syscallarg(int) fd;
3269 	} */ *uap = v;
3270 	struct proc *p = l->l_proc;
3271 	struct vnode *vp;
3272 	struct file *fp;
3273 	int error;
3274 
3275 	/* getvnode() will use the descriptor for us */
3276 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
3277 		return (error);
3278 	if ((fp->f_flag & FWRITE) == 0) {
3279 		FILE_UNUSE(fp, l);
3280 		return (EBADF);
3281 	}
3282 	vp = (struct vnode *)fp->f_data;
3283 	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
3284 	error = VOP_FSYNC(vp, fp->f_cred, FSYNC_WAIT|FSYNC_DATAONLY, 0, 0, l);
3285 	VOP_UNLOCK(vp, 0);
3286 	FILE_UNUSE(fp, l);
3287 	return (error);
3288 }
3289 
3290 /*
3291  * Rename files, (standard) BSD semantics frontend.
3292  */
3293 /* ARGSUSED */
3294 int
3295 sys_rename(struct lwp *l, void *v, register_t *retval)
3296 {
3297 	struct sys_rename_args /* {
3298 		syscallarg(const char *) from;
3299 		syscallarg(const char *) to;
3300 	} */ *uap = v;
3301 
3302 	return (rename_files(SCARG(uap, from), SCARG(uap, to), l, 0));
3303 }
3304 
3305 /*
3306  * Rename files, POSIX semantics frontend.
3307  */
3308 /* ARGSUSED */
3309 int
3310 sys___posix_rename(struct lwp *l, void *v, register_t *retval)
3311 {
3312 	struct sys___posix_rename_args /* {
3313 		syscallarg(const char *) from;
3314 		syscallarg(const char *) to;
3315 	} */ *uap = v;
3316 
3317 	return (rename_files(SCARG(uap, from), SCARG(uap, to), l, 1));
3318 }
3319 
3320 /*
3321  * Rename files.  Source and destination must either both be directories,
3322  * or both not be directories.  If target is a directory, it must be empty.
3323  * If `from' and `to' refer to the same object, the value of the `retain'
3324  * argument is used to determine whether `from' will be
3325  *
3326  * (retain == 0)	deleted unless `from' and `to' refer to the same
3327  *			object in the file system's name space (BSD).
3328  * (retain == 1)	always retained (POSIX).
3329  */
3330 static int
3331 rename_files(const char *from, const char *to, struct lwp *l, int retain)
3332 {
3333 	struct mount *mp = NULL;
3334 	struct vnode *tvp, *fvp, *tdvp;
3335 	struct nameidata fromnd, tond;
3336 	struct proc *p;
3337 	int error;
3338 
3339 	NDINIT(&fromnd, DELETE, WANTPARENT | SAVESTART, UIO_USERSPACE,
3340 	    from, l);
3341 	if ((error = namei(&fromnd)) != 0)
3342 		return (error);
3343 	fvp = fromnd.ni_vp;
3344 	error = vn_start_write(fvp, &mp, V_WAIT | V_PCATCH);
3345 	if (error != 0) {
3346 		VOP_ABORTOP(fromnd.ni_dvp, &fromnd.ni_cnd);
3347 		vrele(fromnd.ni_dvp);
3348 		vrele(fvp);
3349 		if (fromnd.ni_startdir)
3350 			vrele(fromnd.ni_startdir);
3351 		PNBUF_PUT(fromnd.ni_cnd.cn_pnbuf);
3352 		return (error);
3353 	}
3354 	NDINIT(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE | SAVESTART |
3355 	    (fvp->v_type == VDIR ? CREATEDIR : 0), UIO_USERSPACE, to, l);
3356 	if ((error = namei(&tond)) != 0) {
3357 		VOP_ABORTOP(fromnd.ni_dvp, &fromnd.ni_cnd);
3358 		vrele(fromnd.ni_dvp);
3359 		vrele(fvp);
3360 		goto out1;
3361 	}
3362 	tdvp = tond.ni_dvp;
3363 	tvp = tond.ni_vp;
3364 
3365 	if (tvp != NULL) {
3366 		if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
3367 			error = ENOTDIR;
3368 			goto out;
3369 		} else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
3370 			error = EISDIR;
3371 			goto out;
3372 		}
3373 	}
3374 
3375 	if (fvp == tdvp)
3376 		error = EINVAL;
3377 
3378 	/*
3379 	 * Source and destination refer to the same object.
3380 	 */
3381 	if (fvp == tvp) {
3382 		if (retain)
3383 			error = -1;
3384 		else if (fromnd.ni_dvp == tdvp &&
3385 		    fromnd.ni_cnd.cn_namelen == tond.ni_cnd.cn_namelen &&
3386 		    !memcmp(fromnd.ni_cnd.cn_nameptr,
3387 		          tond.ni_cnd.cn_nameptr,
3388 		          fromnd.ni_cnd.cn_namelen))
3389 		error = -1;
3390 	}
3391 
3392 #if NVERIEXEC > 0
3393 	if (!error)
3394 		error = veriexec_renamechk(fvp, fromnd.ni_dirp, tvp,
3395 		    tond.ni_dirp, l);
3396 #endif /* NVERIEXEC > 0 */
3397 
3398 out:
3399 	p = l->l_proc;
3400 	if (!error) {
3401 		VOP_LEASE(tdvp, l, l->l_cred, LEASE_WRITE);
3402 		if (fromnd.ni_dvp != tdvp)
3403 			VOP_LEASE(fromnd.ni_dvp, l, l->l_cred, LEASE_WRITE);
3404 		if (tvp) {
3405 			VOP_LEASE(tvp, l, l->l_cred, LEASE_WRITE);
3406 		}
3407 		error = VOP_RENAME(fromnd.ni_dvp, fromnd.ni_vp, &fromnd.ni_cnd,
3408 				   tond.ni_dvp, tond.ni_vp, &tond.ni_cnd);
3409 	} else {
3410 		VOP_ABORTOP(tond.ni_dvp, &tond.ni_cnd);
3411 		if (tdvp == tvp)
3412 			vrele(tdvp);
3413 		else
3414 			vput(tdvp);
3415 		if (tvp)
3416 			vput(tvp);
3417 		VOP_ABORTOP(fromnd.ni_dvp, &fromnd.ni_cnd);
3418 		vrele(fromnd.ni_dvp);
3419 		vrele(fvp);
3420 	}
3421 	vrele(tond.ni_startdir);
3422 	PNBUF_PUT(tond.ni_cnd.cn_pnbuf);
3423 out1:
3424 	vn_finished_write(mp, 0);
3425 	if (fromnd.ni_startdir)
3426 		vrele(fromnd.ni_startdir);
3427 	PNBUF_PUT(fromnd.ni_cnd.cn_pnbuf);
3428 	return (error == -1 ? 0 : error);
3429 }
3430 
3431 /*
3432  * Make a directory file.
3433  */
3434 /* ARGSUSED */
3435 int
3436 sys_mkdir(struct lwp *l, void *v, register_t *retval)
3437 {
3438 	struct sys_mkdir_args /* {
3439 		syscallarg(const char *) path;
3440 		syscallarg(int) mode;
3441 	} */ *uap = v;
3442 	struct proc *p = l->l_proc;
3443 	struct mount *mp;
3444 	struct vnode *vp;
3445 	struct vattr vattr;
3446 	int error;
3447 	struct nameidata nd;
3448 
3449 restart:
3450 	NDINIT(&nd, CREATE, LOCKPARENT | CREATEDIR, UIO_USERSPACE,
3451 	    SCARG(uap, path), l);
3452 	if ((error = namei(&nd)) != 0)
3453 		return (error);
3454 	vp = nd.ni_vp;
3455 	if (vp != NULL) {
3456 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
3457 		if (nd.ni_dvp == vp)
3458 			vrele(nd.ni_dvp);
3459 		else
3460 			vput(nd.ni_dvp);
3461 		vrele(vp);
3462 		return (EEXIST);
3463 	}
3464 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3465 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
3466 		if (nd.ni_dvp == vp)
3467 			vrele(nd.ni_dvp);
3468 		else
3469 			vput(nd.ni_dvp);
3470 		if ((error = vn_start_write(NULL, &mp,
3471 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
3472 			return (error);
3473 		goto restart;
3474 	}
3475 	VATTR_NULL(&vattr);
3476 	vattr.va_type = VDIR;
3477 	vattr.va_mode =
3478 	    (SCARG(uap, mode) & ACCESSPERMS) &~ p->p_cwdi->cwdi_cmask;
3479 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
3480 	error = VOP_MKDIR(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
3481 	if (!error)
3482 		vput(nd.ni_vp);
3483 	vn_finished_write(mp, 0);
3484 	return (error);
3485 }
3486 
3487 /*
3488  * Remove a directory file.
3489  */
3490 /* ARGSUSED */
3491 int
3492 sys_rmdir(struct lwp *l, void *v, register_t *retval)
3493 {
3494 	struct sys_rmdir_args /* {
3495 		syscallarg(const char *) path;
3496 	} */ *uap = v;
3497 	struct mount *mp;
3498 	struct vnode *vp;
3499 	int error;
3500 	struct nameidata nd;
3501 
3502 restart:
3503 	NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF, UIO_USERSPACE,
3504 	    SCARG(uap, path), l);
3505 	if ((error = namei(&nd)) != 0)
3506 		return (error);
3507 	vp = nd.ni_vp;
3508 	if (vp->v_type != VDIR) {
3509 		error = ENOTDIR;
3510 		goto out;
3511 	}
3512 	/*
3513 	 * No rmdir "." please.
3514 	 */
3515 	if (nd.ni_dvp == vp) {
3516 		error = EINVAL;
3517 		goto out;
3518 	}
3519 	/*
3520 	 * The root of a mounted filesystem cannot be deleted.
3521 	 */
3522 	if (vp->v_flag & VROOT) {
3523 		error = EBUSY;
3524 		goto out;
3525 	}
3526 	if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
3527 		VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
3528 		if (nd.ni_dvp == vp)
3529 			vrele(nd.ni_dvp);
3530 		else
3531 			vput(nd.ni_dvp);
3532 		vput(vp);
3533 		if ((error = vn_start_write(NULL, &mp,
3534 		    V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
3535 			return (error);
3536 		goto restart;
3537 	}
3538 	VOP_LEASE(nd.ni_dvp, l, l->l_cred, LEASE_WRITE);
3539 	VOP_LEASE(vp, l, l->l_cred, LEASE_WRITE);
3540 	error = VOP_RMDIR(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
3541 	vn_finished_write(mp, 0);
3542 	return (error);
3543 
3544 out:
3545 	VOP_ABORTOP(nd.ni_dvp, &nd.ni_cnd);
3546 	if (nd.ni_dvp == vp)
3547 		vrele(nd.ni_dvp);
3548 	else
3549 		vput(nd.ni_dvp);
3550 	vput(vp);
3551 	return (error);
3552 }
3553 
3554 /*
3555  * Read a block of directory entries in a file system independent format.
3556  */
3557 int
3558 sys___getdents30(struct lwp *l, void *v, register_t *retval)
3559 {
3560 	struct sys___getdents30_args /* {
3561 		syscallarg(int) fd;
3562 		syscallarg(char *) buf;
3563 		syscallarg(size_t) count;
3564 	} */ *uap = v;
3565 	struct proc *p = l->l_proc;
3566 	struct file *fp;
3567 	int error, done;
3568 
3569 	/* getvnode() will use the descriptor for us */
3570 	if ((error = getvnode(p->p_fd, SCARG(uap, fd), &fp)) != 0)
3571 		return (error);
3572 	if ((fp->f_flag & FREAD) == 0) {
3573 		error = EBADF;
3574 		goto out;
3575 	}
3576 	error = vn_readdir(fp, SCARG(uap, buf), UIO_USERSPACE,
3577 			SCARG(uap, count), &done, l, 0, 0);
3578 #ifdef KTRACE
3579 	if (!error && KTRPOINT(p, KTR_GENIO)) {
3580 		struct iovec iov;
3581 		iov.iov_base = SCARG(uap, buf);
3582 		iov.iov_len = done;
3583 		ktrgenio(l, SCARG(uap, fd), UIO_READ, &iov, done, 0);
3584 	}
3585 #endif
3586 	*retval = done;
3587  out:
3588 	FILE_UNUSE(fp, l);
3589 	return (error);
3590 }
3591 
3592 /*
3593  * Set the mode mask for creation of filesystem nodes.
3594  */
3595 int
3596 sys_umask(struct lwp *l, void *v, register_t *retval)
3597 {
3598 	struct sys_umask_args /* {
3599 		syscallarg(mode_t) newmask;
3600 	} */ *uap = v;
3601 	struct proc *p = l->l_proc;
3602 	struct cwdinfo *cwdi;
3603 
3604 	cwdi = p->p_cwdi;
3605 	*retval = cwdi->cwdi_cmask;
3606 	cwdi->cwdi_cmask = SCARG(uap, newmask) & ALLPERMS;
3607 	return (0);
3608 }
3609 
3610 /*
3611  * Void all references to file by ripping underlying filesystem
3612  * away from vnode.
3613  */
3614 /* ARGSUSED */
3615 int
3616 sys_revoke(struct lwp *l, void *v, register_t *retval)
3617 {
3618 	struct sys_revoke_args /* {
3619 		syscallarg(const char *) path;
3620 	} */ *uap = v;
3621 	struct mount *mp;
3622 	struct vnode *vp;
3623 	struct vattr vattr;
3624 	int error;
3625 	struct nameidata nd;
3626 
3627 	NDINIT(&nd, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), l);
3628 	if ((error = namei(&nd)) != 0)
3629 		return (error);
3630 	vp = nd.ni_vp;
3631 	if ((error = VOP_GETATTR(vp, &vattr, l->l_cred, l)) != 0)
3632 		goto out;
3633 	if (kauth_cred_geteuid(l->l_cred) != vattr.va_uid &&
3634 	    (error = kauth_authorize_generic(l->l_cred,
3635 	    KAUTH_GENERIC_ISSUSER, &l->l_acflag)) != 0)
3636 		goto out;
3637 	if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
3638 		goto out;
3639 	if (vp->v_usecount > 1 || (vp->v_flag & (VALIASED | VLAYER)))
3640 		VOP_REVOKE(vp, REVOKEALL);
3641 	vn_finished_write(mp, 0);
3642 out:
3643 	vrele(vp);
3644 	return (error);
3645 }
3646 
3647 /*
3648  * Convert a user file descriptor to a kernel file entry.
3649  */
3650 int
3651 getvnode(struct filedesc *fdp, int fd, struct file **fpp)
3652 {
3653 	struct vnode *vp;
3654 	struct file *fp;
3655 
3656 	if ((fp = fd_getfile(fdp, fd)) == NULL)
3657 		return (EBADF);
3658 
3659 	FILE_USE(fp);
3660 
3661 	if (fp->f_type != DTYPE_VNODE) {
3662 		FILE_UNUSE(fp, NULL);
3663 		return (EINVAL);
3664 	}
3665 
3666 	vp = (struct vnode *)fp->f_data;
3667 	if (vp->v_type == VBAD) {
3668 		FILE_UNUSE(fp, NULL);
3669 		return (EBADF);
3670 	}
3671 
3672 	*fpp = fp;
3673 	return (0);
3674 }
3675