vfs_vnops.c revision 1.173
1/*	$NetBSD: vfs_vnops.c,v 1.173 2010/06/18 16:29:02 hannken Exp $	*/
2
3/*-
4 * Copyright (c) 2009 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32/*
33 * Copyright (c) 1982, 1986, 1989, 1993
34 *	The Regents of the University of California.  All rights reserved.
35 * (c) UNIX System Laboratories, Inc.
36 * All or some portions of this file are derived from material licensed
37 * to the University of California by American Telephone and Telegraph
38 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
39 * the permission of UNIX System Laboratories, Inc.
40 *
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
43 * are met:
44 * 1. Redistributions of source code must retain the above copyright
45 *    notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 *    notice, this list of conditions and the following disclaimer in the
48 *    documentation and/or other materials provided with the distribution.
49 * 3. Neither the name of the University nor the names of its contributors
50 *    may be used to endorse or promote products derived from this software
51 *    without specific prior written permission.
52 *
53 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
54 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
55 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
56 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
57 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
58 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
59 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
60 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
61 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
62 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
63 * SUCH DAMAGE.
64 *
65 *	@(#)vfs_vnops.c	8.14 (Berkeley) 6/15/95
66 */
67
68#include <sys/cdefs.h>
69__KERNEL_RCSID(0, "$NetBSD: vfs_vnops.c,v 1.173 2010/06/18 16:29:02 hannken Exp $");
70
71#include "veriexec.h"
72
73#include <sys/param.h>
74#include <sys/systm.h>
75#include <sys/kernel.h>
76#include <sys/file.h>
77#include <sys/stat.h>
78#include <sys/buf.h>
79#include <sys/proc.h>
80#include <sys/mount.h>
81#include <sys/namei.h>
82#include <sys/vnode.h>
83#include <sys/ioctl.h>
84#include <sys/tty.h>
85#include <sys/poll.h>
86#include <sys/kauth.h>
87#include <sys/syslog.h>
88#include <sys/fstrans.h>
89#include <sys/atomic.h>
90#include <sys/filedesc.h>
91#include <sys/wapbl.h>
92
93#include <miscfs/specfs/specdev.h>
94#include <miscfs/fifofs/fifo.h>
95
96#include <uvm/uvm_extern.h>
97#include <uvm/uvm_readahead.h>
98
99#ifdef UNION
100#include <fs/union/union.h>
101#endif
102
103int (*vn_union_readdir_hook) (struct vnode **, struct file *, struct lwp *);
104
105#include <sys/verified_exec.h>
106
107static int vn_read(file_t *fp, off_t *offset, struct uio *uio,
108	    kauth_cred_t cred, int flags);
109static int vn_write(file_t *fp, off_t *offset, struct uio *uio,
110	    kauth_cred_t cred, int flags);
111static int vn_closefile(file_t *fp);
112static int vn_poll(file_t *fp, int events);
113static int vn_fcntl(file_t *fp, u_int com, void *data);
114static int vn_statfile(file_t *fp, struct stat *sb);
115static int vn_ioctl(file_t *fp, u_long com, void *data);
116
117const struct fileops vnops = {
118	.fo_read = vn_read,
119	.fo_write = vn_write,
120	.fo_ioctl = vn_ioctl,
121	.fo_fcntl = vn_fcntl,
122	.fo_poll = vn_poll,
123	.fo_stat = vn_statfile,
124	.fo_close = vn_closefile,
125	.fo_kqfilter = vn_kqfilter,
126	.fo_restart = fnullop_restart,
127};
128
129/*
130 * Common code for vnode open operations.
131 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
132 */
133int
134vn_open(struct nameidata *ndp, int fmode, int cmode)
135{
136	struct vnode *vp;
137	struct lwp *l = curlwp;
138	kauth_cred_t cred = l->l_cred;
139	struct vattr va;
140	int error;
141	char *path;
142
143	ndp->ni_cnd.cn_flags &= TRYEMULROOT | NOCHROOT;
144
145	if (fmode & O_CREAT) {
146		ndp->ni_cnd.cn_nameiop = CREATE;
147		ndp->ni_cnd.cn_flags |= LOCKPARENT | LOCKLEAF;
148		if ((fmode & O_EXCL) == 0 &&
149		    ((fmode & O_NOFOLLOW) == 0))
150			ndp->ni_cnd.cn_flags |= FOLLOW;
151	} else {
152		ndp->ni_cnd.cn_nameiop = LOOKUP;
153		ndp->ni_cnd.cn_flags |= LOCKLEAF;
154		if ((fmode & O_NOFOLLOW) == 0)
155			ndp->ni_cnd.cn_flags |= FOLLOW;
156	}
157
158	VERIEXEC_PATH_GET(ndp->ni_dirp, ndp->ni_segflg, ndp->ni_dirp, path);
159
160	error = namei(ndp);
161	if (error)
162		goto out;
163
164	vp = ndp->ni_vp;
165
166#if NVERIEXEC > 0
167	error = veriexec_openchk(l, ndp->ni_vp, ndp->ni_dirp, fmode);
168	if (error)
169		goto bad;
170#endif /* NVERIEXEC > 0 */
171
172	if (fmode & O_CREAT) {
173		if (ndp->ni_vp == NULL) {
174			vattr_null(&va);
175			va.va_type = VREG;
176			va.va_mode = cmode;
177			if (fmode & O_EXCL)
178				 va.va_vaflags |= VA_EXCLUSIVE;
179			error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
180					   &ndp->ni_cnd, &va);
181			if (error)
182				goto out;
183			fmode &= ~O_TRUNC;
184			vp = ndp->ni_vp;
185		} else {
186			VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd);
187			if (ndp->ni_dvp == ndp->ni_vp)
188				vrele(ndp->ni_dvp);
189			else
190				vput(ndp->ni_dvp);
191			ndp->ni_dvp = NULL;
192			vp = ndp->ni_vp;
193			if (fmode & O_EXCL) {
194				error = EEXIST;
195				goto bad;
196			}
197			fmode &= ~O_CREAT;
198		}
199	} else {
200		vp = ndp->ni_vp;
201	}
202	if (vp->v_type == VSOCK) {
203		error = EOPNOTSUPP;
204		goto bad;
205	}
206	if (ndp->ni_vp->v_type == VLNK) {
207		error = EFTYPE;
208		goto bad;
209	}
210
211	if ((fmode & O_CREAT) == 0) {
212		error = vn_openchk(vp, cred, fmode);
213		if (error != 0)
214			goto bad;
215	}
216
217	if (fmode & O_TRUNC) {
218		VOP_UNLOCK(vp, 0);			/* XXX */
219
220		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);	/* XXX */
221		vattr_null(&va);
222		va.va_size = 0;
223		error = VOP_SETATTR(vp, &va, cred);
224		if (error != 0)
225			goto bad;
226	}
227	if ((error = VOP_OPEN(vp, fmode, cred)) != 0)
228		goto bad;
229	if (fmode & FWRITE) {
230		mutex_enter(&vp->v_interlock);
231		vp->v_writecount++;
232		mutex_exit(&vp->v_interlock);
233	}
234
235bad:
236	if (error)
237		vput(vp);
238out:
239	VERIEXEC_PATH_PUT(path);
240	return (error);
241}
242
243/*
244 * Check for write permissions on the specified vnode.
245 * Prototype text segments cannot be written.
246 */
247int
248vn_writechk(struct vnode *vp)
249{
250
251	/*
252	 * If the vnode is in use as a process's text,
253	 * we can't allow writing.
254	 */
255	if (vp->v_iflag & VI_TEXT)
256		return (ETXTBSY);
257	return (0);
258}
259
260int
261vn_openchk(struct vnode *vp, kauth_cred_t cred, int fflags)
262{
263	int permbits = 0;
264	int error;
265
266	if ((fflags & FREAD) != 0) {
267		permbits = VREAD;
268	}
269	if ((fflags & (FWRITE | O_TRUNC)) != 0) {
270		permbits |= VWRITE;
271		if (vp->v_type == VDIR) {
272			error = EISDIR;
273			goto bad;
274		}
275		error = vn_writechk(vp);
276		if (error != 0)
277			goto bad;
278	}
279	error = VOP_ACCESS(vp, permbits, cred);
280bad:
281	return error;
282}
283
284/*
285 * Mark a vnode as having executable mappings.
286 */
287void
288vn_markexec(struct vnode *vp)
289{
290
291	if ((vp->v_iflag & VI_EXECMAP) != 0) {
292		/* Safe unlocked, as long as caller holds a reference. */
293		return;
294	}
295
296	mutex_enter(&vp->v_interlock);
297	if ((vp->v_iflag & VI_EXECMAP) == 0) {
298		atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages);
299		atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages);
300		vp->v_iflag |= VI_EXECMAP;
301	}
302	mutex_exit(&vp->v_interlock);
303}
304
305/*
306 * Mark a vnode as being the text of a process.
307 * Fail if the vnode is currently writable.
308 */
309int
310vn_marktext(struct vnode *vp)
311{
312
313	if ((vp->v_iflag & (VI_TEXT|VI_EXECMAP)) == (VI_TEXT|VI_EXECMAP)) {
314		/* Safe unlocked, as long as caller holds a reference. */
315		return (0);
316	}
317
318	mutex_enter(&vp->v_interlock);
319	if (vp->v_writecount != 0) {
320		KASSERT((vp->v_iflag & VI_TEXT) == 0);
321		mutex_exit(&vp->v_interlock);
322		return (ETXTBSY);
323	}
324	if ((vp->v_iflag & VI_EXECMAP) == 0) {
325		atomic_add_int(&uvmexp.filepages, -vp->v_uobj.uo_npages);
326		atomic_add_int(&uvmexp.execpages, vp->v_uobj.uo_npages);
327	}
328	vp->v_iflag |= (VI_TEXT | VI_EXECMAP);
329	mutex_exit(&vp->v_interlock);
330	return (0);
331}
332
333/*
334 * Vnode close call
335 *
336 * Note: takes an unlocked vnode, while VOP_CLOSE takes a locked node.
337 */
338int
339vn_close(struct vnode *vp, int flags, kauth_cred_t cred)
340{
341	int error;
342
343	if (flags & FWRITE) {
344		mutex_enter(&vp->v_interlock);
345		vp->v_writecount--;
346		mutex_exit(&vp->v_interlock);
347	}
348	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
349	error = VOP_CLOSE(vp, flags, cred);
350	vput(vp);
351	return (error);
352}
353
354static int
355enforce_rlimit_fsize(struct vnode *vp, struct uio *uio, int ioflag)
356{
357	struct lwp *l = curlwp;
358	off_t testoff;
359
360	if (uio->uio_rw != UIO_WRITE || vp->v_type != VREG)
361		return 0;
362
363	KASSERT(VOP_ISLOCKED(vp) == LK_EXCLUSIVE);
364	if (ioflag & IO_APPEND)
365		testoff = vp->v_size;
366	else
367		testoff = uio->uio_offset;
368
369	if (testoff + uio->uio_resid >
370	    l->l_proc->p_rlimit[RLIMIT_FSIZE].rlim_cur) {
371		mutex_enter(proc_lock);
372		psignal(l->l_proc, SIGXFSZ);
373		mutex_exit(proc_lock);
374		return EFBIG;
375	}
376
377	return 0;
378}
379
380/*
381 * Package up an I/O request on a vnode into a uio and do it.
382 */
383int
384vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
385    enum uio_seg segflg, int ioflg, kauth_cred_t cred, size_t *aresid,
386    struct lwp *l)
387{
388	struct uio auio;
389	struct iovec aiov;
390	int error;
391
392	if ((ioflg & IO_NODELOCKED) == 0) {
393		if (rw == UIO_READ) {
394			vn_lock(vp, LK_SHARED | LK_RETRY);
395		} else /* UIO_WRITE */ {
396			vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
397		}
398	}
399	auio.uio_iov = &aiov;
400	auio.uio_iovcnt = 1;
401	aiov.iov_base = base;
402	aiov.iov_len = len;
403	auio.uio_resid = len;
404	auio.uio_offset = offset;
405	auio.uio_rw = rw;
406	if (segflg == UIO_SYSSPACE) {
407		UIO_SETUP_SYSSPACE(&auio);
408	} else {
409		auio.uio_vmspace = l->l_proc->p_vmspace;
410	}
411
412	if ((error = enforce_rlimit_fsize(vp, &auio, ioflg)) != 0)
413		goto out;
414
415	if (rw == UIO_READ) {
416		error = VOP_READ(vp, &auio, ioflg, cred);
417	} else {
418		error = VOP_WRITE(vp, &auio, ioflg, cred);
419	}
420
421	if (aresid)
422		*aresid = auio.uio_resid;
423	else
424		if (auio.uio_resid && error == 0)
425			error = EIO;
426
427 out:
428	if ((ioflg & IO_NODELOCKED) == 0) {
429		VOP_UNLOCK(vp, 0);
430	}
431	return (error);
432}
433
434int
435vn_readdir(file_t *fp, char *bf, int segflg, u_int count, int *done,
436    struct lwp *l, off_t **cookies, int *ncookies)
437{
438	struct vnode *vp = (struct vnode *)fp->f_data;
439	struct iovec aiov;
440	struct uio auio;
441	int error, eofflag;
442
443	/* Limit the size on any kernel buffers used by VOP_READDIR */
444	count = min(MAXBSIZE, count);
445
446unionread:
447	if (vp->v_type != VDIR)
448		return (EINVAL);
449	aiov.iov_base = bf;
450	aiov.iov_len = count;
451	auio.uio_iov = &aiov;
452	auio.uio_iovcnt = 1;
453	auio.uio_rw = UIO_READ;
454	if (segflg == UIO_SYSSPACE) {
455		UIO_SETUP_SYSSPACE(&auio);
456	} else {
457		KASSERT(l == curlwp);
458		auio.uio_vmspace = l->l_proc->p_vmspace;
459	}
460	auio.uio_resid = count;
461	vn_lock(vp, LK_SHARED | LK_RETRY);
462	auio.uio_offset = fp->f_offset;
463	error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, cookies,
464		    ncookies);
465	mutex_enter(&fp->f_lock);
466	fp->f_offset = auio.uio_offset;
467	mutex_exit(&fp->f_lock);
468	VOP_UNLOCK(vp, 0);
469	if (error)
470		return (error);
471
472	if (count == auio.uio_resid && vn_union_readdir_hook) {
473		struct vnode *ovp = vp;
474
475		error = (*vn_union_readdir_hook)(&vp, fp, l);
476		if (error)
477			return (error);
478		if (vp != ovp)
479			goto unionread;
480	}
481
482	if (count == auio.uio_resid && (vp->v_vflag & VV_ROOT) &&
483	    (vp->v_mount->mnt_flag & MNT_UNION)) {
484		struct vnode *tvp = vp;
485		vp = vp->v_mount->mnt_vnodecovered;
486		vref(vp);
487		mutex_enter(&fp->f_lock);
488		fp->f_data = vp;
489		fp->f_offset = 0;
490		mutex_exit(&fp->f_lock);
491		vrele(tvp);
492		goto unionread;
493	}
494	*done = count - auio.uio_resid;
495	return error;
496}
497
498/*
499 * File table vnode read routine.
500 */
501static int
502vn_read(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
503    int flags)
504{
505	struct vnode *vp = (struct vnode *)fp->f_data;
506	int count, error, ioflag, fflag;
507
508	ioflag = IO_ADV_ENCODE(fp->f_advice);
509	fflag = fp->f_flag;
510	if (fflag & FNONBLOCK)
511		ioflag |= IO_NDELAY;
512	if ((fflag & (FFSYNC | FRSYNC)) == (FFSYNC | FRSYNC))
513		ioflag |= IO_SYNC;
514	if (fflag & FALTIO)
515		ioflag |= IO_ALTSEMANTICS;
516	if (fflag & FDIRECT)
517		ioflag |= IO_DIRECT;
518	vn_lock(vp, LK_SHARED | LK_RETRY);
519	uio->uio_offset = *offset;
520	count = uio->uio_resid;
521	error = VOP_READ(vp, uio, ioflag, cred);
522	if (flags & FOF_UPDATE_OFFSET)
523		*offset += count - uio->uio_resid;
524	VOP_UNLOCK(vp, 0);
525	return (error);
526}
527
528/*
529 * File table vnode write routine.
530 */
531static int
532vn_write(file_t *fp, off_t *offset, struct uio *uio, kauth_cred_t cred,
533    int flags)
534{
535	struct vnode *vp = (struct vnode *)fp->f_data;
536	int count, error, ioflag, fflag;
537
538	ioflag = IO_ADV_ENCODE(fp->f_advice) | IO_UNIT;
539	fflag = fp->f_flag;
540	if (vp->v_type == VREG && (fflag & O_APPEND))
541		ioflag |= IO_APPEND;
542	if (fflag & FNONBLOCK)
543		ioflag |= IO_NDELAY;
544	if (fflag & FFSYNC ||
545	    (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
546		ioflag |= IO_SYNC;
547	else if (fflag & FDSYNC)
548		ioflag |= IO_DSYNC;
549	if (fflag & FALTIO)
550		ioflag |= IO_ALTSEMANTICS;
551	if (fflag & FDIRECT)
552		ioflag |= IO_DIRECT;
553	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
554	uio->uio_offset = *offset;
555	count = uio->uio_resid;
556
557	if ((error = enforce_rlimit_fsize(vp, uio, ioflag)) != 0)
558		goto out;
559
560	error = VOP_WRITE(vp, uio, ioflag, cred);
561
562	if (flags & FOF_UPDATE_OFFSET) {
563		if (ioflag & IO_APPEND) {
564			/*
565			 * SUSv3 describes behaviour for count = 0 as following:
566			 * "Before any action ... is taken, and if nbyte is zero
567			 * and the file is a regular file, the write() function
568			 * ... in the absence of errors ... shall return zero
569			 * and have no other results."
570			 */
571			if (count)
572				*offset = uio->uio_offset;
573		} else
574			*offset += count - uio->uio_resid;
575	}
576
577 out:
578	VOP_UNLOCK(vp, 0);
579	return (error);
580}
581
582/*
583 * File table vnode stat routine.
584 */
585static int
586vn_statfile(file_t *fp, struct stat *sb)
587{
588	struct vnode *vp = fp->f_data;
589	int error;
590
591	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
592	error = vn_stat(vp, sb);
593	VOP_UNLOCK(vp, 0);
594	return error;
595}
596
597int
598vn_stat(struct vnode *vp, struct stat *sb)
599{
600	struct vattr va;
601	int error;
602	mode_t mode;
603
604	error = VOP_GETATTR(vp, &va, kauth_cred_get());
605	if (error)
606		return (error);
607	/*
608	 * Copy from vattr table
609	 */
610	sb->st_dev = va.va_fsid;
611	sb->st_ino = va.va_fileid;
612	mode = va.va_mode;
613	switch (vp->v_type) {
614	case VREG:
615		mode |= S_IFREG;
616		break;
617	case VDIR:
618		mode |= S_IFDIR;
619		break;
620	case VBLK:
621		mode |= S_IFBLK;
622		break;
623	case VCHR:
624		mode |= S_IFCHR;
625		break;
626	case VLNK:
627		mode |= S_IFLNK;
628		break;
629	case VSOCK:
630		mode |= S_IFSOCK;
631		break;
632	case VFIFO:
633		mode |= S_IFIFO;
634		break;
635	default:
636		return (EBADF);
637	};
638	sb->st_mode = mode;
639	sb->st_nlink = va.va_nlink;
640	sb->st_uid = va.va_uid;
641	sb->st_gid = va.va_gid;
642	sb->st_rdev = va.va_rdev;
643	sb->st_size = va.va_size;
644	sb->st_atimespec = va.va_atime;
645	sb->st_mtimespec = va.va_mtime;
646	sb->st_ctimespec = va.va_ctime;
647	sb->st_birthtimespec = va.va_birthtime;
648	sb->st_blksize = va.va_blocksize;
649	sb->st_flags = va.va_flags;
650	sb->st_gen = 0;
651	sb->st_blocks = va.va_bytes / S_BLKSIZE;
652	return (0);
653}
654
655/*
656 * File table vnode fcntl routine.
657 */
658static int
659vn_fcntl(file_t *fp, u_int com, void *data)
660{
661	struct vnode *vp = fp->f_data;
662	int error;
663
664	error = VOP_FCNTL(vp, com, data, fp->f_flag, kauth_cred_get());
665	return (error);
666}
667
668/*
669 * File table vnode ioctl routine.
670 */
671static int
672vn_ioctl(file_t *fp, u_long com, void *data)
673{
674	struct vnode *vp = fp->f_data, *ovp;
675	struct vattr vattr;
676	int error;
677
678	switch (vp->v_type) {
679
680	case VREG:
681	case VDIR:
682		if (com == FIONREAD) {
683			error = VOP_GETATTR(vp, &vattr,
684			    kauth_cred_get());
685			if (error)
686				return (error);
687			*(int *)data = vattr.va_size - fp->f_offset;
688			return (0);
689		}
690		if ((com == FIONWRITE) || (com == FIONSPACE)) {
691			/*
692			 * Files don't have send queues, so there never
693			 * are any bytes in them, nor is there any
694			 * open space in them.
695			 */
696			*(int *)data = 0;
697			return (0);
698		}
699		if (com == FIOGETBMAP) {
700			daddr_t *block;
701
702			if (*(daddr_t *)data < 0)
703				return (EINVAL);
704			block = (daddr_t *)data;
705			return (VOP_BMAP(vp, *block, NULL, block, NULL));
706		}
707		if (com == OFIOGETBMAP) {
708			daddr_t ibn, obn;
709
710			if (*(int32_t *)data < 0)
711				return (EINVAL);
712			ibn = (daddr_t)*(int32_t *)data;
713			error = VOP_BMAP(vp, ibn, NULL, &obn, NULL);
714			*(int32_t *)data = (int32_t)obn;
715			return error;
716		}
717		if (com == FIONBIO || com == FIOASYNC)	/* XXX */
718			return (0);			/* XXX */
719		/* fall into ... */
720	case VFIFO:
721	case VCHR:
722	case VBLK:
723		error = VOP_IOCTL(vp, com, data, fp->f_flag,
724		    kauth_cred_get());
725		if (error == 0 && com == TIOCSCTTY) {
726			vref(vp);
727			mutex_enter(proc_lock);
728			ovp = curproc->p_session->s_ttyvp;
729			curproc->p_session->s_ttyvp = vp;
730			mutex_exit(proc_lock);
731			if (ovp != NULL)
732				vrele(ovp);
733		}
734		return (error);
735
736	default:
737		return (EPASSTHROUGH);
738	}
739}
740
741/*
742 * File table vnode poll routine.
743 */
744static int
745vn_poll(file_t *fp, int events)
746{
747
748	return (VOP_POLL(fp->f_data, events));
749}
750
751/*
752 * File table vnode kqfilter routine.
753 */
754int
755vn_kqfilter(file_t *fp, struct knote *kn)
756{
757
758	return (VOP_KQFILTER(fp->f_data, kn));
759}
760
761/*
762 * Check that the vnode is still valid, and if so
763 * acquire requested lock.
764 */
765int
766vn_lock(struct vnode *vp, int flags)
767{
768	int error;
769
770#if 0
771	KASSERT(vp->v_usecount > 0 || (flags & LK_INTERLOCK) != 0
772	    || (vp->v_iflag & VI_ONWORKLST) != 0);
773#endif
774	KASSERT((flags &
775	    ~(LK_INTERLOCK|LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT|LK_RETRY))
776	    == 0);
777
778#ifdef DIAGNOSTIC
779	if (wapbl_vphaswapbl(vp))
780		WAPBL_JUNLOCK_ASSERT(wapbl_vptomp(vp));
781#endif
782
783	do {
784		/*
785		 * XXX PR 37706 forced unmount of file systems is unsafe.
786		 * Race between vclean() and this the remaining problem.
787		 */
788		if (vp->v_iflag & VI_XLOCK) {
789			if ((flags & LK_INTERLOCK) == 0) {
790				mutex_enter(&vp->v_interlock);
791			}
792			flags &= ~LK_INTERLOCK;
793			if (flags & LK_NOWAIT) {
794				mutex_exit(&vp->v_interlock);
795				return EBUSY;
796			}
797			vwait(vp, VI_XLOCK);
798			mutex_exit(&vp->v_interlock);
799			error = ENOENT;
800		} else {
801			if ((flags & LK_INTERLOCK) != 0) {
802				mutex_exit(&vp->v_interlock);
803			}
804			flags &= ~LK_INTERLOCK;
805			error = VOP_LOCK(vp, (flags & ~LK_RETRY));
806			if (error == 0 || error == EDEADLK || error == EBUSY)
807				return (error);
808		}
809	} while (flags & LK_RETRY);
810	return (error);
811}
812
813/*
814 * File table vnode close routine.
815 */
816static int
817vn_closefile(file_t *fp)
818{
819
820	return vn_close(fp->f_data, fp->f_flag, fp->f_cred);
821}
822
823/*
824 * Simplified in-kernel wrapper calls for extended attribute access.
825 * Both calls pass in a NULL credential, authorizing a "kernel" access.
826 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
827 */
828int
829vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
830    const char *attrname, size_t *buflen, void *bf, struct lwp *l)
831{
832	struct uio auio;
833	struct iovec aiov;
834	int error;
835
836	aiov.iov_len = *buflen;
837	aiov.iov_base = bf;
838
839	auio.uio_iov = &aiov;
840	auio.uio_iovcnt = 1;
841	auio.uio_rw = UIO_READ;
842	auio.uio_offset = 0;
843	auio.uio_resid = *buflen;
844	UIO_SETUP_SYSSPACE(&auio);
845
846	if ((ioflg & IO_NODELOCKED) == 0)
847		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
848
849	error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL);
850
851	if ((ioflg & IO_NODELOCKED) == 0)
852		VOP_UNLOCK(vp, 0);
853
854	if (error == 0)
855		*buflen = *buflen - auio.uio_resid;
856
857	return (error);
858}
859
860/*
861 * XXX Failure mode if partially written?
862 */
863int
864vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
865    const char *attrname, size_t buflen, const void *bf, struct lwp *l)
866{
867	struct uio auio;
868	struct iovec aiov;
869	int error;
870
871	aiov.iov_len = buflen;
872	aiov.iov_base = __UNCONST(bf);		/* XXXUNCONST kills const */
873
874	auio.uio_iov = &aiov;
875	auio.uio_iovcnt = 1;
876	auio.uio_rw = UIO_WRITE;
877	auio.uio_offset = 0;
878	auio.uio_resid = buflen;
879	UIO_SETUP_SYSSPACE(&auio);
880
881	if ((ioflg & IO_NODELOCKED) == 0) {
882		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
883	}
884
885	error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL);
886
887	if ((ioflg & IO_NODELOCKED) == 0) {
888		VOP_UNLOCK(vp, 0);
889	}
890
891	return (error);
892}
893
894int
895vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
896    const char *attrname, struct lwp *l)
897{
898	int error;
899
900	if ((ioflg & IO_NODELOCKED) == 0) {
901		vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
902	}
903
904	error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL);
905	if (error == EOPNOTSUPP)
906		error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL, NULL);
907
908	if ((ioflg & IO_NODELOCKED) == 0) {
909		VOP_UNLOCK(vp, 0);
910	}
911
912	return (error);
913}
914
915void
916vn_ra_allocctx(struct vnode *vp)
917{
918	struct uvm_ractx *ra = NULL;
919
920	KASSERT(mutex_owned(&vp->v_interlock));
921
922	if (vp->v_type != VREG) {
923		return;
924	}
925	if (vp->v_ractx != NULL) {
926		return;
927	}
928	if (vp->v_ractx == NULL) {
929		mutex_exit(&vp->v_interlock);
930		ra = uvm_ra_allocctx();
931		mutex_enter(&vp->v_interlock);
932		if (ra != NULL && vp->v_ractx == NULL) {
933			vp->v_ractx = ra;
934			ra = NULL;
935		}
936	}
937	if (ra != NULL) {
938		uvm_ra_freectx(ra);
939	}
940}
941
942int
943vn_fifo_bypass(void *v)
944{
945	struct vop_generic_args *ap = v;
946
947	return VOCALL(fifo_vnodeop_p, ap->a_desc->vdesc_offset, v);
948}
949