vfs_vnops.c revision 1.87 1 /* $NetBSD: vfs_vnops.c,v 1.87 2005/04/20 13:44:46 blymn 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 1.87 2005/04/20 13:44:46 blymn 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/malloc.h>
52 #include <sys/mount.h>
53 #include <sys/namei.h>
54 #include <sys/vnode.h>
55 #include <sys/ioctl.h>
56 #include <sys/tty.h>
57 #include <sys/poll.h>
58
59 #include <miscfs/specfs/specdev.h>
60
61 #include <uvm/uvm_extern.h>
62
63 #ifdef UNION
64 #include <fs/union/union.h>
65 #endif
66
67 #if defined(LKM) || defined(UNION)
68 int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct proc *);
69 #endif
70
71 #ifdef VERIFIED_EXEC
72 #include <sys/verified_exec.h>
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 const 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 mount *mp;
101 struct proc *p = ndp->ni_cnd.cn_proc;
102 struct ucred *cred = p->p_ucred;
103 struct vattr va;
104 int error;
105 #ifdef NEVER /* for the moment I am not convinced this is needed since NDINIT should do this lookup...XXXX blymn */
106 char pathbuf[MAXPATHLEN];
107 unsigned pathlen;
108
109 if (ndp->ni_segflg == UIO_SYSSPACE)
110 error = copystr(pathbuf, ndp->ni_dirp, MAXPATHLEN, &pathlen);
111 else
112 error = copyinstr(pathbuf, ndp->ni_dirp,MAXPATHLEN, &pathlen);
113 #endif
114
115 restart:
116 if (fmode & O_CREAT) {
117 ndp->ni_cnd.cn_nameiop = CREATE;
118 ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
119 if ((fmode & O_EXCL) == 0 &&
120 ((fmode & O_NOFOLLOW) == 0))
121 ndp->ni_cnd.cn_flags |= FOLLOW;
122 if ((error = namei(ndp)) != 0)
123 return (error);
124 if (ndp->ni_vp == NULL) {
125 VATTR_NULL(&va);
126 va.va_type = VREG;
127 va.va_mode = cmode;
128 if (fmode & O_EXCL)
129 va.va_vaflags |= VA_EXCLUSIVE;
130 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
131 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
132 vput(ndp->ni_dvp);
133 if ((error = vn_start_write(NULL, &mp,
134 V_WAIT | V_SLEEPONLY | V_PCATCH)) != 0)
135 return (error);
136 goto restart;
137 }
138 VOP_LEASE(ndp->ni_dvp, p, cred, LEASE_WRITE);
139 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
140 &ndp->ni_cnd, &va);
141 vn_finished_write(mp, 0);
142 if (error)
143 return (error);
144 fmode &= ~O_TRUNC;
145 vp = ndp->ni_vp;
146 } else {
147 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
148 if (ndp->ni_dvp == ndp->ni_vp)
149 vrele(ndp->ni_dvp);
150 else
151 vput(ndp->ni_dvp);
152 ndp->ni_dvp = NULL;
153 vp = ndp->ni_vp;
154 if (fmode & O_EXCL) {
155 error = EEXIST;
156 goto bad;
157 }
158 fmode &= ~O_CREAT;
159 }
160 } else {
161 ndp->ni_cnd.cn_nameiop = LOOKUP;
162 ndp->ni_cnd.cn_flags = LOCKLEAF;
163 if ((fmode & O_NOFOLLOW) == 0)
164 ndp->ni_cnd.cn_flags |= FOLLOW;
165 if ((error = namei(ndp)) != 0)
166 return (error);
167 vp = ndp->ni_vp;
168 }
169 if (vp->v_type == VSOCK) {
170 error = EOPNOTSUPP;
171 goto bad;
172 }
173 if (ndp->ni_vp->v_type == VLNK) {
174 error = EFTYPE;
175 goto bad;
176 }
177
178 #ifdef VERIFIED_EXEC
179 if ((error = VOP_GETATTR(vp, &va, cred, p)) != 0)
180 goto bad;
181 #endif
182
183 if ((fmode & O_CREAT) == 0) {
184 #ifdef VERIFIED_EXEC
185 /* XXX may need pathbuf instead */
186 if ((vp->v_type == VREG) &&
187 ((error = veriexec_verify(p, vp, &va, ndp->ni_dirp,
188 VERIEXEC_FILE)) != 0))
189 goto bad;
190 #endif
191 if (fmode & FREAD) {
192 if ((error = VOP_ACCESS(vp, VREAD, cred, p)) != 0)
193 goto bad;
194
195 }
196
197 if (fmode & (FWRITE | O_TRUNC)) {
198 if (vp->v_type == VDIR) {
199 error = EISDIR;
200 goto bad;
201 }
202 if ((error = vn_writechk(vp)) != 0 ||
203 (error = VOP_ACCESS(vp, VWRITE, cred, p)) != 0)
204 goto bad;
205 #ifdef VERIFIED_EXEC
206 /*
207 * If file has a fingerprint then
208 * deny the write request, otherwise
209 * invalidate the status so we don't
210 * keep checking for the file having
211 * a fingerprint.
212 */
213 if ((vp->fp_status == FINGERPRINT_VALID) ||
214 (vp->fp_status == FINGERPRINT_INDIRECT)) {
215 printf(
216 "writing to fingerprinted file for dev %lu, file %lu\n",
217 va.va_fsid, va.va_fileid);
218 if (securelevel >= 2) {
219 error = EPERM;
220 goto bad;
221 } else {
222 vp->fp_status = FINGERPRINT_NOMATCH;
223 }
224 }
225 #endif
226 }
227 }
228
229 if (fmode & O_TRUNC) {
230 VOP_UNLOCK(vp, 0); /* XXX */
231 if ((error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0) {
232 vput(vp);
233 return (error);
234 }
235 VOP_LEASE(vp, p, cred, LEASE_WRITE);
236 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */
237 VATTR_NULL(&va);
238 va.va_size = 0;
239 error = VOP_SETATTR(vp, &va, cred, p);
240 vn_finished_write(mp, 0);
241 if (error != 0)
242 goto bad;
243 }
244 if ((error = VOP_OPEN(vp, fmode, cred, p)) != 0)
245 goto bad;
246 if (vp->v_type == VREG &&
247 uvn_attach(vp, fmode & FWRITE ? VM_PROT_WRITE : 0) == NULL) {
248 error = EIO;
249 goto bad;
250 }
251 if (fmode & FWRITE)
252 vp->v_writecount++;
253
254 return (0);
255 bad:
256 vput(vp);
257 return (error);
258 }
259
260 /*
261 * Check for write permissions on the specified vnode.
262 * Prototype text segments cannot be written.
263 */
264 int
265 vn_writechk(vp)
266 struct vnode *vp;
267 {
268
269 /*
270 * If the vnode is in use as a process's text,
271 * we can't allow writing.
272 */
273 if (vp->v_flag & VTEXT)
274 return (ETXTBSY);
275 return (0);
276 }
277
278 /*
279 * Mark a vnode as having executable mappings.
280 */
281 void
282 vn_markexec(vp)
283 struct vnode *vp;
284 {
285 if ((vp->v_flag & VEXECMAP) == 0) {
286 uvmexp.filepages -= vp->v_uobj.uo_npages;
287 uvmexp.execpages += vp->v_uobj.uo_npages;
288 }
289 vp->v_flag |= VEXECMAP;
290 }
291
292 /*
293 * Mark a vnode as being the text of a process.
294 * Fail if the vnode is currently writable.
295 */
296 int
297 vn_marktext(vp)
298 struct vnode *vp;
299 {
300
301 if (vp->v_writecount != 0) {
302 KASSERT((vp->v_flag & VTEXT) == 0);
303 return (ETXTBSY);
304 }
305 vp->v_flag |= VTEXT;
306 vn_markexec(vp);
307 return (0);
308 }
309
310 /*
311 * Vnode close call
312 *
313 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node.
314 */
315 int
316 vn_close(vp, flags, cred, p)
317 struct vnode *vp;
318 int flags;
319 struct ucred *cred;
320 struct proc *p;
321 {
322 int error;
323
324 if (flags & FWRITE)
325 vp->v_writecount--;
326 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
327 error = VOP_CLOSE(vp, flags, cred, p);
328 vput(vp);
329 return (error);
330 }
331
332 /*
333 * Package up an I/O request on a vnode into a uio and do it.
334 */
335 int
336 vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p)
337 enum uio_rw rw;
338 struct vnode *vp;
339 caddr_t base;
340 int len;
341 off_t offset;
342 enum uio_seg segflg;
343 int ioflg;
344 struct ucred *cred;
345 size_t *aresid;
346 struct proc *p;
347 {
348 struct uio auio;
349 struct iovec aiov;
350 struct mount *mp;
351 int error;
352
353 if ((ioflg & IO_NODELOCKED) == 0) {
354 if (rw == UIO_READ) {
355 vn_lock(vp, LK_SHARED | LK_RETRY);
356 } else /* UIO_WRITE */ {
357 if (vp->v_type != VCHR &&
358 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH))
359 != 0)
360 return (error);
361 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
362 }
363 }
364 auio.uio_iov = &aiov;
365 auio.uio_iovcnt = 1;
366 aiov.iov_base = base;
367 aiov.iov_len = len;
368 auio.uio_resid = len;
369 auio.uio_offset = offset;
370 auio.uio_segflg = segflg;
371 auio.uio_rw = rw;
372 auio.uio_procp = p;
373 if (rw == UIO_READ) {
374 error = VOP_READ(vp, &auio, ioflg, cred);
375 } else {
376 error = VOP_WRITE(vp, &auio, ioflg, cred);
377 }
378 if (aresid)
379 *aresid = auio.uio_resid;
380 else
381 if (auio.uio_resid && error == 0)
382 error = EIO;
383 if ((ioflg & IO_NODELOCKED) == 0) {
384 if (rw == UIO_WRITE)
385 vn_finished_write(mp, 0);
386 VOP_UNLOCK(vp, 0);
387 }
388 return (error);
389 }
390
391 int
392 vn_readdir(fp, buf, segflg, count, done, p, cookies, ncookies)
393 struct file *fp;
394 char *buf;
395 int segflg, *done, *ncookies;
396 u_int count;
397 struct proc *p;
398 off_t **cookies;
399 {
400 struct vnode *vp = (struct vnode *)fp->f_data;
401 struct iovec aiov;
402 struct uio auio;
403 int error, eofflag;
404
405 unionread:
406 if (vp->v_type != VDIR)
407 return (EINVAL);
408 aiov.iov_base = buf;
409 aiov.iov_len = count;
410 auio.uio_iov = &aiov;
411 auio.uio_iovcnt = 1;
412 auio.uio_rw = UIO_READ;
413 auio.uio_segflg = segflg;
414 auio.uio_procp = p;
415 auio.uio_resid = count;
416 vn_lock(vp, LK_SHARED | LK_RETRY);
417 auio.uio_offset = fp->f_offset;
418 error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies,
419 ncookies);
420 fp->f_offset = auio.uio_offset;
421 VOP_UNLOCK(vp, 0);
422 if (error)
423 return (error);
424
425 #if defined(UNION) || defined(LKM)
426 if (count == auio.uio_resid && vn_union_readdir_hook) {
427 struct vnode *ovp = vp;
428
429 error = (*vn_union_readdir_hook)(&vp, fp, p);
430 if (error)
431 return (error);
432 if (vp != ovp)
433 goto unionread;
434 }
435 #endif /* UNION || LKM */
436
437 if (count == auio.uio_resid && (vp->v_flag & VROOT) &&
438 (vp->v_mount->mnt_flag & MNT_UNION)) {
439 struct vnode *tvp = vp;
440 vp = vp->v_mount->mnt_vnodecovered;
441 VREF(vp);
442 fp->f_data = vp;
443 fp->f_offset = 0;
444 vrele(tvp);
445 goto unionread;
446 }
447 *done = count - auio.uio_resid;
448 return error;
449 }
450
451 /*
452 * File table vnode read routine.
453 */
454 static int
455 vn_read(fp, offset, uio, cred, flags)
456 struct file *fp;
457 off_t *offset;
458 struct uio *uio;
459 struct ucred *cred;
460 int flags;
461 {
462 struct vnode *vp = (struct vnode *)fp->f_data;
463 int count, error, ioflag = 0;
464
465 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_READ);
466 if (fp->f_flag & FNONBLOCK)
467 ioflag |= IO_NDELAY;
468 if ((fp->f_flag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC))
469 ioflag |= IO_SYNC;
470 if (fp->f_flag & FALTIO)
471 ioflag |= IO_ALTSEMANTICS;
472 vn_lock(vp, LK_SHARED | LK_RETRY);
473 uio->uio_offset = *offset;
474 count = uio->uio_resid;
475 error = VOP_READ(vp, uio, ioflag, cred);
476 if (flags & FOF_UPDATE_OFFSET)
477 *offset += count - uio->uio_resid;
478 VOP_UNLOCK(vp, 0);
479 return (error);
480 }
481
482 /*
483 * File table vnode write routine.
484 */
485 static int
486 vn_write(fp, offset, uio, cred, flags)
487 struct file *fp;
488 off_t *offset;
489 struct uio *uio;
490 struct ucred *cred;
491 int flags;
492 {
493 struct vnode *vp = (struct vnode *)fp->f_data;
494 struct mount *mp;
495 int count, error, ioflag = IO_UNIT;
496
497 if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
498 ioflag |= IO_APPEND;
499 if (fp->f_flag & FNONBLOCK)
500 ioflag |= IO_NDELAY;
501 if (fp->f_flag & FFSYNC ||
502 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
503 ioflag |= IO_SYNC;
504 else if (fp->f_flag & FDSYNC)
505 ioflag |= IO_DSYNC;
506 if (fp->f_flag & FALTIO)
507 ioflag |= IO_ALTSEMANTICS;
508 mp = NULL;
509 if (vp->v_type != VCHR &&
510 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH)) != 0)
511 return (error);
512 VOP_LEASE(vp, uio->uio_procp, cred, LEASE_WRITE);
513 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
514 uio->uio_offset = *offset;
515 count = uio->uio_resid;
516 error = VOP_WRITE(vp, uio, ioflag, cred);
517 if (flags & FOF_UPDATE_OFFSET) {
518 if (ioflag & IO_APPEND)
519 *offset = uio->uio_offset;
520 else
521 *offset += count - uio->uio_resid;
522 }
523 VOP_UNLOCK(vp, 0);
524 vn_finished_write(mp, 0);
525 return (error);
526 }
527
528 /*
529 * File table vnode stat routine.
530 */
531 static int
532 vn_statfile(fp, sb, p)
533 struct file *fp;
534 struct stat *sb;
535 struct proc *p;
536 {
537 struct vnode *vp = (struct vnode *)fp->f_data;
538
539 return vn_stat(vp, sb, p);
540 }
541
542 int
543 vn_stat(vp, sb, p)
544 struct vnode *vp;
545 struct stat *sb;
546 struct proc *p;
547 {
548 struct vattr va;
549 int error;
550 mode_t mode;
551
552 error = VOP_GETATTR(vp, &va, p->p_ucred, p);
553 if (error)
554 return (error);
555 /*
556 * Copy from vattr table
557 */
558 sb->st_dev = va.va_fsid;
559 sb->st_ino = va.va_fileid;
560 mode = va.va_mode;
561 switch (vp->v_type) {
562 case VREG:
563 mode |= S_IFREG;
564 break;
565 case VDIR:
566 mode |= S_IFDIR;
567 break;
568 case VBLK:
569 mode |= S_IFBLK;
570 break;
571 case VCHR:
572 mode |= S_IFCHR;
573 break;
574 case VLNK:
575 mode |= S_IFLNK;
576 break;
577 case VSOCK:
578 mode |= S_IFSOCK;
579 break;
580 case VFIFO:
581 mode |= S_IFIFO;
582 break;
583 default:
584 return (EBADF);
585 };
586 sb->st_mode = mode;
587 sb->st_nlink = va.va_nlink;
588 sb->st_uid = va.va_uid;
589 sb->st_gid = va.va_gid;
590 sb->st_rdev = va.va_rdev;
591 sb->st_size = va.va_size;
592 sb->st_atimespec = va.va_atime;
593 sb->st_mtimespec = va.va_mtime;
594 sb->st_ctimespec = va.va_ctime;
595 sb->st_birthtimespec = va.va_birthtime;
596 sb->st_blksize = va.va_blocksize;
597 sb->st_flags = va.va_flags;
598 sb->st_gen = 0;
599 sb->st_blocks = va.va_bytes / S_BLKSIZE;
600 return (0);
601 }
602
603 /*
604 * File table vnode fcntl routine.
605 */
606 static int
607 vn_fcntl(fp, com, data, p)
608 struct file *fp;
609 u_int com;
610 void *data;
611 struct proc *p;
612 {
613 struct vnode *vp = ((struct vnode *)fp->f_data);
614 int error;
615
616 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
617 error = VOP_FCNTL(vp, com, data, fp->f_flag, p->p_ucred, p);
618 VOP_UNLOCK(vp, 0);
619 return (error);
620 }
621
622 /*
623 * File table vnode ioctl routine.
624 */
625 static int
626 vn_ioctl(fp, com, data, p)
627 struct file *fp;
628 u_long com;
629 void *data;
630 struct proc *p;
631 {
632 struct vnode *vp = ((struct vnode *)fp->f_data);
633 struct vattr vattr;
634 int error;
635
636 switch (vp->v_type) {
637
638 case VREG:
639 case VDIR:
640 if (com == FIONREAD) {
641 error = VOP_GETATTR(vp, &vattr, p->p_ucred, p);
642 if (error)
643 return (error);
644 *(int *)data = vattr.va_size - fp->f_offset;
645 return (0);
646 }
647 if ((com == FIONWRITE) || (com == FIONSPACE)) {
648 /*
649 * Files don't have send queues, so there never
650 * are any bytes in them, nor is there any
651 * open space in them.
652 */
653 *(int *)data = 0;
654 return (0);
655 }
656 if (com == FIOGETBMAP) {
657 daddr_t *block;
658
659 if (*(daddr_t *)data < 0)
660 return (EINVAL);
661 block = (daddr_t *)data;
662 return (VOP_BMAP(vp, *block, NULL, block, NULL));
663 }
664 if (com == OFIOGETBMAP) {
665 daddr_t ibn, obn;
666
667 if (*(int32_t *)data < 0)
668 return (EINVAL);
669 ibn = (daddr_t)*(int32_t *)data;
670 error = VOP_BMAP(vp, ibn, NULL, &obn, NULL);
671 *(int32_t *)data = (int32_t)obn;
672 return error;
673 }
674 if (com == FIONBIO || com == FIOASYNC) /* XXX */
675 return (0); /* XXX */
676 /* fall into ... */
677 case VFIFO:
678 case VCHR:
679 case VBLK:
680 error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p);
681 if (error == 0 && com == TIOCSCTTY) {
682 if (p->p_session->s_ttyvp)
683 vrele(p->p_session->s_ttyvp);
684 p->p_session->s_ttyvp = vp;
685 VREF(vp);
686 }
687 return (error);
688
689 default:
690 return (EPASSTHROUGH);
691 }
692 }
693
694 /*
695 * File table vnode poll routine.
696 */
697 static int
698 vn_poll(fp, events, p)
699 struct file *fp;
700 int events;
701 struct proc *p;
702 {
703
704 return (VOP_POLL(((struct vnode *)fp->f_data), events, p));
705 }
706
707 /*
708 * File table vnode kqfilter routine.
709 */
710 int
711 vn_kqfilter(fp, kn)
712 struct file *fp;
713 struct knote *kn;
714 {
715
716 return (VOP_KQFILTER((struct vnode *)fp->f_data, kn));
717 }
718
719 /*
720 * Check that the vnode is still valid, and if so
721 * acquire requested lock.
722 */
723 int
724 vn_lock(vp, flags)
725 struct vnode *vp;
726 int flags;
727 {
728 int error;
729
730 #if 0
731 KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0
732 || (vp->v_flag & VONWORKLST) != 0);
733 #endif
734
735 do {
736 if ((flags & LK_INTERLOCK) == 0)
737 simple_lock(&vp->v_interlock);
738 if (vp->v_flag & VXLOCK) {
739 if (flags & LK_NOWAIT) {
740 simple_unlock(&vp->v_interlock);
741 return EBUSY;
742 }
743 vp->v_flag |= VXWANT;
744 ltsleep(vp, PINOD | PNORELOCK,
745 "vn_lock", 0, &vp->v_interlock);
746 error = ENOENT;
747 } else {
748 error = VOP_LOCK(vp,
749 (flags & ~LK_RETRY) | LK_INTERLOCK);
750 if (error == 0 || error == EDEADLK || error == EBUSY)
751 return (error);
752 }
753 flags &= ~LK_INTERLOCK;
754 } while (flags & LK_RETRY);
755 return (error);
756 }
757
758 /*
759 * File table vnode close routine.
760 */
761 static int
762 vn_closefile(fp, p)
763 struct file *fp;
764 struct proc *p;
765 {
766
767 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag,
768 fp->f_cred, p));
769 }
770
771 /*
772 * Enable LK_CANRECURSE on lock. Return prior status.
773 */
774 u_int
775 vn_setrecurse(vp)
776 struct vnode *vp;
777 {
778 struct lock *lkp = &vp->v_lock;
779 u_int retval = lkp->lk_flags & LK_CANRECURSE;
780
781 lkp->lk_flags |= LK_CANRECURSE;
782 return retval;
783 }
784
785 /*
786 * Called when done with locksetrecurse.
787 */
788 void
789 vn_restorerecurse(vp, flags)
790 struct vnode *vp;
791 u_int flags;
792 {
793 struct lock *lkp = &vp->v_lock;
794
795 lkp->lk_flags &= ~LK_CANRECURSE;
796 lkp->lk_flags |= flags;
797 }
798
799 int
800 vn_cow_establish(struct vnode *vp,
801 int (*func)(void *, struct buf *), void *cookie)
802 {
803 int s;
804 struct spec_cow_entry *e;
805
806 MALLOC(e, struct spec_cow_entry *, sizeof(struct spec_cow_entry),
807 M_DEVBUF, M_WAITOK);
808 e->ce_func = func;
809 e->ce_cookie = cookie;
810
811 SPEC_COW_LOCK(vp->v_specinfo, s);
812 vp->v_spec_cow_req++;
813 while (vp->v_spec_cow_count > 0)
814 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0,
815 &vp->v_spec_cow_slock);
816
817 SLIST_INSERT_HEAD(&vp->v_spec_cow_head, e, ce_list);
818
819 vp->v_spec_cow_req--;
820 if (vp->v_spec_cow_req == 0)
821 wakeup(&vp->v_spec_cow_req);
822 SPEC_COW_UNLOCK(vp->v_specinfo, s);
823
824 return 0;
825 }
826
827 int
828 vn_cow_disestablish(struct vnode *vp,
829 int (*func)(void *, struct buf *), void *cookie)
830 {
831 int s;
832 struct spec_cow_entry *e;
833
834 SPEC_COW_LOCK(vp->v_specinfo, s);
835 vp->v_spec_cow_req++;
836 while (vp->v_spec_cow_count > 0)
837 ltsleep(&vp->v_spec_cow_req, PRIBIO, "cowlist", 0,
838 &vp->v_spec_cow_slock);
839
840 SLIST_FOREACH(e, &vp->v_spec_cow_head, ce_list)
841 if (e->ce_func == func && e->ce_cookie == cookie) {
842 SLIST_REMOVE(&vp->v_spec_cow_head, e,
843 spec_cow_entry, ce_list);
844 FREE(e, M_DEVBUF);
845 break;
846 }
847
848 vp->v_spec_cow_req--;
849 if (vp->v_spec_cow_req == 0)
850 wakeup(&vp->v_spec_cow_req);
851 SPEC_COW_UNLOCK(vp->v_specinfo, s);
852
853 return e ? 0 : EINVAL;
854 }
855
856 /*
857 * Simplified in-kernel wrapper calls for extended attribute access.
858 * Both calls pass in a NULL credential, authorizing a "kernel" access.
859 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
860 */
861 int
862 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
863 const char *attrname, size_t *buflen, void *buf, struct proc *p)
864 {
865 struct uio auio;
866 struct iovec aiov;
867 int error;
868
869 aiov.iov_len = *buflen;
870 aiov.iov_base = buf;
871
872 auio.uio_iov = &aiov;
873 auio.uio_iovcnt = 1;
874 auio.uio_rw = UIO_READ;
875 auio.uio_segflg = UIO_SYSSPACE;
876 auio.uio_procp = p;
877 auio.uio_offset = 0;
878 auio.uio_resid = *buflen;
879
880 if ((ioflg & IO_NODELOCKED) == 0)
881 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
882
883 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
884 p);
885
886 if ((ioflg & IO_NODELOCKED) == 0)
887 VOP_UNLOCK(vp, 0);
888
889 if (error == 0)
890 *buflen = *buflen - auio.uio_resid;
891
892 return (error);
893 }
894
895 /*
896 * XXX Failure mode if partially written?
897 */
898 int
899 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
900 const char *attrname, size_t buflen, const void *buf, struct proc *p)
901 {
902 struct uio auio;
903 struct iovec aiov;
904 struct mount *mp;
905 int error;
906
907 aiov.iov_len = buflen;
908 aiov.iov_base = (caddr_t) buf; /* XXX kills const */
909
910 auio.uio_iov = &aiov;
911 auio.uio_iovcnt = 1;
912 auio.uio_rw = UIO_WRITE;
913 auio.uio_segflg = UIO_SYSSPACE;
914 auio.uio_procp = p;
915 auio.uio_offset = 0;
916 auio.uio_resid = buflen;
917
918 if ((ioflg & IO_NODELOCKED) == 0) {
919 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
920 return (error);
921 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
922 }
923
924 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, p);
925
926 if ((ioflg & IO_NODELOCKED) == 0) {
927 vn_finished_write(mp, 0);
928 VOP_UNLOCK(vp, 0);
929 }
930
931 return (error);
932 }
933
934 int
935 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
936 const char *attrname, struct proc *p)
937 {
938 struct mount *mp;
939 int error;
940
941 if ((ioflg & IO_NODELOCKED) == 0) {
942 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
943 return (error);
944 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
945 }
946
947 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, p);
948 if (error == EOPNOTSUPP)
949 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
950 NULL, p);
951
952 if ((ioflg & IO_NODELOCKED) == 0) {
953 vn_finished_write(mp, 0);
954 VOP_UNLOCK(vp, 0);
955 }
956
957 return (error);
958 }
959