vfs_vnops.c revision 1.73 1 /* $NetBSD: vfs_vnops.c,v 1.73 2003/08/07 16:32:04 agc Exp $ */
2
3 /*
4 * Copyright (c) 1982, 1986, 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_vnops.c 8.14 (Berkeley) 6/15/95
37 */
38
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.73 2003/08/07 16:32:04 agc Exp $");
41
42 #include "fs_union.h"
43
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/kernel.h>
47 #include <sys/file.h>
48 #include <sys/stat.h>
49 #include <sys/buf.h>
50 #include <sys/proc.h>
51 #include <sys/mount.h>
52 #include <sys/namei.h>
53 #include <sys/vnode.h>
54 #include <sys/ioctl.h>
55 #include <sys/tty.h>
56 #include <sys/poll.h>
57
58 #include <uvm/uvm_extern.h>
59
60 #ifdef UNION
61 #include <fs/union/union.h>
62 #endif
63
64 #if defined(LKM) || defined(UNION)
65 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct proc *);
66 #endif
67
68 #ifdef VERIFIED_EXEC
69 #include <sys/verified_exec.h>
70
71 extern LIST_HEAD(veriexec_devhead, veriexec_dev_list) veriexec_dev_head;
72 extern struct veriexec_devhead veriexec_file_dev_head;
73 #endif
74
75 static int vn_read(struct file *fp, off_t *offset, struct uio *uio,
76 struct ucred *cred, int flags);
77 static int vn_write(struct file *fp, off_t *offset, struct uio *uio,
78 struct ucred *cred, int flags);
79 static int vn_closefile(struct file *fp, struct proc *p);
80 static int vn_poll(struct file *fp, int events, struct proc *p);
81 static int vn_fcntl(struct file *fp, u_int com, void *data, struct proc *p);
82 static int vn_statfile(struct file *fp, struct stat *sb, struct proc *p);
83 static int vn_ioctl(struct file *fp, u_long com, void *data, struct proc *p);
84
85 struct fileops vnops = {
86 vn_read, vn_write, vn_ioctl, vn_fcntl, vn_poll,
87 vn_statfile, vn_closefile, vn_kqfilter
88 };
89
90 /*
91 * Common code for vnode open operations.
92 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
93 */
94 int
95 vn_open(ndp, fmode, cmode)
96 struct nameidata *ndp;
97 int fmode, cmode;
98 {
99 struct vnode *vp;
100 struct proc *p = ndp->ni_cnd.cn_proc;
101 struct ucred *cred = p->p_ucred;
102 struct vattr va;
103 int error;
104 #ifdef VERIFIED_EXEC
105 char got_dev;
106 struct veriexec_inode_list *veriexec_node;
107 char fingerprint[MAXFINGERPRINTLEN];
108 #endif
109
110 if (fmode & O_CREAT) {
111 ndp->ni_cnd.cn_nameiop = CREATE;
112 ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
113 if ((fmode & O_EXCL) == 0 &&
114 ((fmode & O_NOFOLLOW) == 0))
115 ndp->ni_cnd.cn_flags |= FOLLOW;
116 if ((error = namei(ndp)) != 0)
117 return (error);
118 if (ndp->ni_vp == NULL) {
119 VATTR_NULL(&va);
120 va.va_type = VREG;
121 va.va_mode = cmode;
122 if (fmode & O_EXCL)
123 va.va_vaflags |= VA_EXCLUSIVE;
124 VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE);
125 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
126 &ndp->ni_cnd, &va);
127 if (error)
128 return (error);
129 fmode &= ~O_TRUNC;
130 vp = ndp->ni_vp;
131 } else {
132 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
133 if (ndp->ni_dvp == ndp->ni_vp)
134 vrele(ndp->ni_dvp);
135 else
136 vput(ndp->ni_dvp);
137 ndp->ni_dvp = NULL;
138 vp = ndp->ni_vp;
139 if (fmode & O_EXCL) {
140 error = EEXIST;
141 goto bad;
142 }
143 if (ndp->ni_vp->v_type == VLNK) {
144 error = EFTYPE;
145 goto bad;
146 }
147 fmode &= ~O_CREAT;
148 }
149 } else {
150 ndp->ni_cnd.cn_nameiop = LOOKUP;
151 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF;
152 if ((error = namei(ndp)) != 0)
153 return (error);
154 vp = ndp->ni_vp;
155 }
156 if (vp->v_type == VSOCK) {
157 error = EOPNOTSUPP;
158 goto bad;
159 }
160
161 #ifdef VERIFIED_EXEC
162 veriexec_node = NULL;
163
164 if ((error = VOP_GETATTR(vp, &va, cred, p)) != 0)
165 goto bad;
166 #endif
167
168 if ((fmode & O_CREAT) == 0) {
169 #ifdef VERIFIED_EXEC
170 /*
171 * Look for the file on the fingerprint lists iff
172 * it has not been seen before.
173 */
174 if ((vp->fp_status == FINGERPRINT_INVALID) ||
175 (vp->fp_status == FINGERPRINT_NODEV)) {
176 /* check the file list for the finger print */
177 veriexec_node = get_veriexec_inode(&veriexec_file_dev_head,
178 va.va_fsid,
179 va.va_fileid,
180 &got_dev);
181 if (veriexec_node == NULL) {
182 /* failing that, check the exec list */
183 veriexec_node = get_veriexec_inode(
184 &veriexec_dev_head, va.va_fsid,
185 va.va_fileid, &got_dev);
186 }
187
188 if ((veriexec_node == NULL) && (got_dev == 1))
189 vp->fp_status = FINGERPRINT_NOENTRY;
190
191 if (veriexec_node != NULL) {
192 if ((error = evaluate_fingerprint(vp,
193 veriexec_node, p, va.va_size,
194 fingerprint)) != 0)
195 goto bad;
196
197 if (fingerprintcmp(veriexec_node,
198 fingerprint) == 0) {
199 /* fingerprint ok */
200 vp->fp_status = FINGERPRINT_VALID;
201 #ifdef VERIFIED_EXEC_DEBUG
202 printf(
203 "file fingerprint matches for dev %lu, file %lu\n",
204 va.va_fsid, va.va_fileid);
205 #endif
206 } else {
207 vp->fp_status = FINGERPRINT_NOMATCH;
208 }
209 }
210 }
211 #endif
212
213 if (fmode & FREAD) {
214 if ((error = VOP_ACCESS(vp, VREAD, cred, p)) != 0)
215 goto bad;
216
217 #ifdef VERIFIED_EXEC
218 /* file is on finger print list */
219 if (vp->fp_status == FINGERPRINT_NOMATCH) {
220 /* fingerprint bad */
221 printf(
222 "file fingerprint does not match on dev %lu, file %lu\n",
223 va.va_fsid, va.va_fileid);
224 if (securelevel > 2) {
225 error = EPERM;
226 goto bad;
227 }
228 }
229 #endif
230 }
231 if (fmode & (FWRITE | O_TRUNC)) {
232 if (vp->v_type == VDIR) {
233 error = EISDIR;
234 goto bad;
235 }
236 if ((error = vn_writechk(vp)) != 0 ||
237 (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0)
238 goto bad;
239 #ifdef VERIFIED_EXEC
240 /*
241 * If file has a fingerprint then
242 * deny the write request, otherwise
243 * invalidate the status so we don't
244 * keep checking for the file having
245 * a fingerprint.
246 */
247 if (vp->fp_status == FINGERPRINT_VALID) {
248 printf(
249 "writing to fingerprinted file for dev %lu, file %lu\n",
250 va.va_fsid, va.va_fileid);
251 if (securelevel > 2) {
252 error = EPERM;
253 goto bad;
254 } else {
255 vp->fp_status = FINGERPRINT_INVALID;
256 }
257 }
258 #endif
259 }
260 }
261 if (fmode & O_TRUNC) {
262 VOP_UNLOCK(vp, 0); /* XXX */
263 VOP_LEASE(vp, p, cred, LEASE_WRITE);
264 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */
265 VATTR_NULL(&va);
266 va.va_size = 0;
267 if ((error = VOP_SETATTR(vp, &va, cred, p)) != 0)
268 goto bad;
269 }
270 if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0)
271 goto bad;
272 if (vp->v_type == VREG &&
273 uvn_attach(vp, fmode & FWRITE ? VM_PROT_WRITE : 0) == NULL) {
274 error = EIO;
275 goto bad;
276 }
277 if (fmode & FWRITE)
278 vp->v_writecount++;
279
280 return (0);
281 bad:
282 vput(vp);
283 return (error);
284 }
285
286 /*
287 * Check for write permissions on the specified vnode.
288 * Prototype text segments cannot be written.
289 */
290 int
291 vn_writechk(vp)
292 struct vnode *vp;
293 {
294
295 /*
296 * If the vnode is in use as a process's text,
297 * we can't allow writing.
298 */
299 if (vp->v_flag & VTEXT)
300 return (ETXTBSY);
301 return (0);
302 }
303
304 /*
305 * Mark a vnode as having executable mappings.
306 */
307 void
308 vn_markexec(vp)
309 struct vnode *vp;
310 {
311 if ((vp->v_flag & VEXECMAP) == 0) {
312 uvmexp.filepages -= vp->v_uobj.uo_npages;
313 uvmexp.execpages += vp->v_uobj.uo_npages;
314 }
315 vp->v_flag |= VEXECMAP;
316 }
317
318 /*
319 * Mark a vnode as being the text of a process.
320 * Fail if the vnode is currently writable.
321 */
322 int
323 vn_marktext(vp)
324 struct vnode *vp;
325 {
326
327 if (vp->v_writecount != 0) {
328 KASSERT((vp->v_flag & VTEXT) == 0);
329 return (ETXTBSY);
330 }
331 vp->v_flag |= VTEXT;
332 vn_markexec(vp);
333 return (0);
334 }
335
336 /*
337 * Vnode close call
338 *
339 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node.
340 */
341 int
342 vn_close(vp, flags, cred, p)
343 struct vnode *vp;
344 int flags;
345 struct ucred *cred;
346 struct proc *p;
347 {
348 int error;
349
350 if (flags & FWRITE)
351 vp->v_writecount--;
352 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
353 error = VOP_CLOSE(vp, flags, cred, p);
354 vput(vp);
355 return (error);
356 }
357
358 /*
359 * Package up an I/O request on a vnode into a uio and do it.
360 */
361 int
362 vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
363 enum uio_rw rw;
364 struct vnode *vp;
365 caddr_t base;
366 int len;
367 off_t offset;
368 enum uio_seg segflg;
369 int ioflg;
370 struct ucred *cred;
371 size_t *aresid;
372 struct proc *p;
373 {
374 struct uio auio;
375 struct iovec aiov;
376 int error;
377
378 if ((ioflg & IO_NODELOCKED) == 0) {
379 if (rw == UIO_READ) {
380 vn_lock(vp, LK_SHARED | LK_RETRY);
381 } else {
382 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
383 }
384 }
385 auio.uio_iov = &aiov;
386 auio.uio_iovcnt = 1;
387 aiov.iov_base = base;
388 aiov.iov_len = len;
389 auio.uio_resid = len;
390 auio.uio_offset = offset;
391 auio.uio_segflg = segflg;
392 auio.uio_rw = rw;
393 auio.uio_procp = p;
394 if (rw == UIO_READ) {
395 error = VOP_READ(vp, &auio, ioflg, cred);
396 } else {
397 error = VOP_WRITE(vp, &auio, ioflg, cred);
398 }
399 if (aresid)
400 *aresid = auio.uio_resid;
401 else
402 if (auio.uio_resid && error == 0)
403 error = EIO;
404 if ((ioflg & IO_NODELOCKED) == 0)
405 VOP_UNLOCK(vp, 0);
406 return (error);
407 }
408
409 int
410 vn_readdir(fp, buf, segflg, count, done, p, cookies, ncookies)
411 struct file *fp;
412 char *buf;
413 int segflg, *done, *ncookies;
414 u_int count;
415 struct proc *p;
416 off_t **cookies;
417 {
418 struct vnode *vp = (struct vnode *)fp->f_data;
419 struct iovec aiov;
420 struct uio auio;
421 int error, eofflag;
422
423 unionread:
424 if (vp->v_type != VDIR)
425 return (EINVAL);
426 aiov.iov_base = buf;
427 aiov.iov_len = count;
428 auio.uio_iov = &aiov;
429 auio.uio_iovcnt = 1;
430 auio.uio_rw = UIO_READ;
431 auio.uio_segflg = segflg;
432 auio.uio_procp = p;
433 auio.uio_resid = count;
434 vn_lock(vp, LK_SHARED | LK_RETRY);
435 auio.uio_offset = fp->f_offset;
436 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies,
437 ncookies);
438 fp->f_offset = auio.uio_offset;
439 VOP_UNLOCK(vp, 0);
440 if (error)
441 return (error);
442
443 #if defined(UNION) || defined(LKM)
444 if (count == auio.uio_resid && vn_union_readdir_hook) {
445 struct vnode *ovp = vp;
446
447 error = (*vn_union_readdir_hook)(&vp, fp, p);
448 if (error)
449 return (error);
450 if (vp != ovp)
451 goto unionread;
452 }
453 #endif /* UNION || LKM */
454
455 if (count == auio.uio_resid && (vp->v_flag & VROOT) &&
456 (vp->v_mount->mnt_flag & MNT_UNION)) {
457 struct vnode *tvp = vp;
458 vp = vp->v_mount->mnt_vnodecovered;
459 VREF(vp);
460 fp->f_data = vp;
461 fp->f_offset = 0;
462 vrele(tvp);
463 goto unionread;
464 }
465 *done = count - auio.uio_resid;
466 return error;
467 }
468
469 /*
470 * File table vnode read routine.
471 */
472 static int
473 vn_read(fp, offset, uio, cred, flags)
474 struct file *fp;
475 off_t *offset;
476 struct uio *uio;
477 struct ucred *cred;
478 int flags;
479 {
480 struct vnode *vp = (struct vnode *)fp->f_data;
481 int count, error, ioflag = 0;
482
483 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_READ);
484 if (fp->f_flag & FNONBLOCK)
485 ioflag |= IO_NDELAY;
486 if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC))
487 ioflag |= IO_SYNC;
488 if (fp->f_flag & FALTIO)
489 ioflag |= IO_ALTSEMANTICS;
490 vn_lock(vp, LK_SHARED | LK_RETRY);
491 uio->uio_offset = *offset;
492 count = uio->uio_resid;
493 error = VOP_READ(vp, uio, ioflag, cred);
494 if (flags & FOF_UPDATE_OFFSET)
495 *offset += count - uio->uio_resid;
496 VOP_UNLOCK(vp, 0);
497 return (error);
498 }
499
500 /*
501 * File table vnode write routine.
502 */
503 static int
504 vn_write(fp, offset, uio, cred, flags)
505 struct file *fp;
506 off_t *offset;
507 struct uio *uio;
508 struct ucred *cred;
509 int flags;
510 {
511 struct vnode *vp = (struct vnode *)fp->f_data;
512 int count, error, ioflag = IO_UNIT;
513
514 if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
515 ioflag |= IO_APPEND;
516 if (fp->f_flag & FNONBLOCK)
517 ioflag |= IO_NDELAY;
518 if (fp->f_flag & FFSYNC ||
519 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
520 ioflag |= IO_SYNC;
521 else if (fp->f_flag & FDSYNC)
522 ioflag |= IO_DSYNC;
523 if (fp->f_flag & FALTIO)
524 ioflag |= IO_ALTSEMANTICS;
525 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_WRITE);
526 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
527 uio->uio_offset = *offset;
528 count = uio->uio_resid;
529 error = VOP_WRITE(vp, uio, ioflag, cred);
530 if (flags & FOF_UPDATE_OFFSET) {
531 if (ioflag & IO_APPEND)
532 *offset = uio->uio_offset;
533 else
534 *offset += count - uio->uio_resid;
535 }
536 VOP_UNLOCK(vp, 0);
537 return (error);
538 }
539
540 /*
541 * File table vnode stat routine.
542 */
543 static int
544 vn_statfile(fp, sb, p)
545 struct file *fp;
546 struct stat *sb;
547 struct proc *p;
548 {
549 struct vnode *vp = (struct vnode *)fp->f_data;
550
551 return vn_stat(vp, sb, p);
552 }
553
554 int
555 vn_stat(vp, sb, p)
556 struct vnode *vp;
557 struct stat *sb;
558 struct proc *p;
559 {
560 struct vattr va;
561 int error;
562 mode_t mode;
563
564 error = VOP_GETATTR(vp, &va, p->p_ucred, p);
565 if (error)
566 return (error);
567 /*
568 * Copy from vattr table
569 */
570 sb->st_dev = va.va_fsid;
571 sb->st_ino = va.va_fileid;
572 mode = va.va_mode;
573 switch (vp->v_type) {
574 case VREG:
575 mode |= S_IFREG;
576 break;
577 case VDIR:
578 mode |= S_IFDIR;
579 break;
580 case VBLK:
581 mode |= S_IFBLK;
582 break;
583 case VCHR:
584 mode |= S_IFCHR;
585 break;
586 case VLNK:
587 mode |= S_IFLNK;
588 break;
589 case VSOCK:
590 mode |= S_IFSOCK;
591 break;
592 case VFIFO:
593 mode |= S_IFIFO;
594 break;
595 default:
596 return (EBADF);
597 };
598 sb->st_mode = mode;
599 sb->st_nlink = va.va_nlink;
600 sb->st_uid = va.va_uid;
601 sb->st_gid = va.va_gid;
602 sb->st_rdev = va.va_rdev;
603 sb->st_size = va.va_size;
604 sb->st_atimespec = va.va_atime;
605 sb->st_mtimespec = va.va_mtime;
606 sb->st_ctimespec = va.va_ctime;
607 sb->st_birthtimespec = va.va_birthtime;
608 sb->st_blksize = va.va_blocksize;
609 sb->st_flags = va.va_flags;
610 sb->st_gen = 0;
611 sb->st_blocks = va.va_bytes / S_BLKSIZE;
612 return (0);
613 }
614
615 /*
616 * File table vnode fcntl routine.
617 */
618 static int
619 vn_fcntl(fp, com, data, p)
620 struct file *fp;
621 u_int com;
622 void *data;
623 struct proc *p;
624 {
625 struct vnode *vp = ((struct vnode *)fp->f_data);
626 int error;
627
628 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
629 error = VOP_FCNTL(vp, com, data, fp->f_flag, p->p_ucred, p);
630 VOP_UNLOCK(vp, 0);
631 return (error);
632 }
633
634 /*
635 * File table vnode ioctl routine.
636 */
637 static int
638 vn_ioctl(fp, com, data, p)
639 struct file *fp;
640 u_long com;
641 void *data;
642 struct proc *p;
643 {
644 struct vnode *vp = ((struct vnode *)fp->f_data);
645 struct vattr vattr;
646 int error;
647
648 switch (vp->v_type) {
649
650 case VREG:
651 case VDIR:
652 if (com == FIONREAD) {
653 error = VOP_GETATTR(vp, &vattr, p->p_ucred, p);
654 if (error)
655 return (error);
656 *(int *)data = vattr.va_size - fp->f_offset;
657 return (0);
658 }
659 if (com == FIOGETBMAP) {
660 daddr_t *block;
661
662 if (*(daddr_t *)data < 0)
663 return (EINVAL);
664 block = (daddr_t *)data;
665 return (VOP_BMAP(vp, *block, NULL, block, NULL));
666 }
667 if (com == OFIOGETBMAP) {
668 daddr_t ibn, obn;
669
670 if (*(int32_t *)data < 0)
671 return (EINVAL);
672 ibn = (daddr_t)*(int32_t *)data;
673 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL);
674 *(int32_t *)data = (int32_t)obn;
675 return error;
676 }
677 if (com == FIONBIO || com == FIOASYNC) /* XXX */
678 return (0); /* XXX */
679 /* fall into ... */
680
681 case VFIFO:
682 case VCHR:
683 case VBLK:
684 error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
685 if (error == 0 && com == TIOCSCTTY) {
686 if (p->p_session->s_ttyvp)
687 vrele(p->p_session->s_ttyvp);
688 p->p_session->s_ttyvp = vp;
689 VREF(vp);
690 }
691 return (error);
692
693 default:
694 return (EPASSTHROUGH);
695 }
696 }
697
698 /*
699 * File table vnode poll routine.
700 */
701 static int
702 vn_poll(fp, events, p)
703 struct file *fp;
704 int events;
705 struct proc *p;
706 {
707
708 return (VOP_POLL(((struct vnode *)fp->f_data), events, p));
709 }
710
711 /*
712 * File table vnode kqfilter routine.
713 */
714 int
715 vn_kqfilter(fp, kn)
716 struct file *fp;
717 struct knote *kn;
718 {
719
720 return (VOP_KQFILTER((struct vnode *)fp->f_data, kn));
721 }
722
723 /*
724 * Check that the vnode is still valid, and if so
725 * acquire requested lock.
726 */
727 int
728 vn_lock(vp, flags)
729 struct vnode *vp;
730 int flags;
731 {
732 int error;
733
734 do {
735 if ((flags & LK_INTERLOCK) == 0)
736 simple_lock(&vp->v_interlock);
737 if (vp->v_flag & VXLOCK) {
738 if (flags & LK_NOWAIT) {
739 simple_unlock(&vp->v_interlock);
740 return EBUSY;
741 }
742 vp->v_flag |= VXWANT;
743 ltsleep(vp, PINOD | PNORELOCK,
744 "vn_lock", 0, &vp->v_interlock);
745 error = ENOENT;
746 } else {
747 error = VOP_LOCK(vp, flags | LK_INTERLOCK);
748 if (error == 0 || error == EDEADLK || error == EBUSY)
749 return (error);
750 }
751 flags &= ~LK_INTERLOCK;
752 } while (flags & LK_RETRY);
753 return (error);
754 }
755
756 /*
757 * File table vnode close routine.
758 */
759 static int
760 vn_closefile(fp, p)
761 struct file *fp;
762 struct proc *p;
763 {
764
765 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
766 fp->f_cred, p));
767 }
768
769 /*
770 * Enable LK_CANRECURSE on lock. Return prior status.
771 */
772 u_int
773 vn_setrecurse(vp)
774 struct vnode *vp;
775 {
776 struct lock *lkp = &vp->v_lock;
777 u_int retval = lkp->lk_flags & LK_CANRECURSE;
778
779 lkp->lk_flags |= LK_CANRECURSE;
780 return retval;
781 }
782
783 /*
784 * Called when done with locksetrecurse.
785 */
786 void
787 vn_restorerecurse(vp, flags)
788 struct vnode *vp;
789 u_int flags;
790 {
791 struct lock *lkp = &vp->v_lock;
792
793 lkp->lk_flags &= ~LK_CANRECURSE;
794 lkp->lk_flags |= flags;
795 }
796