1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1989, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)dead_vnops.c	8.1 (Berkeley) 6/10/93
32 * $FreeBSD$
33 */
34
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/mutex.h>
40#include <sys/poll.h>
41#include <sys/vnode.h>
42
43/*
44 * Prototypes for dead operations on vnodes.
45 */
46static vop_lookup_t	dead_lookup;
47static vop_open_t	dead_open;
48static vop_getwritemount_t dead_getwritemount;
49static vop_rename_t	dead_rename;
50static vop_unset_text_t	dead_unset_text;
51
52struct vop_vector dead_vnodeops = {
53	.vop_default =		&default_vnodeops,
54
55	.vop_access =		VOP_EBADF,
56	.vop_advlock =		VOP_EBADF,
57	.vop_bmap =		VOP_EBADF,
58	.vop_create =		VOP_PANIC,
59	.vop_getattr =		VOP_EBADF,
60	.vop_getwritemount =	dead_getwritemount,
61	.vop_inactive =		VOP_NULL,
62	.vop_ioctl =		VOP_EBADF,
63	.vop_link =		VOP_PANIC,
64	.vop_lookup =		dead_lookup,
65	.vop_mkdir =		VOP_PANIC,
66	.vop_mknod =		VOP_PANIC,
67	.vop_open =		dead_open,
68	.vop_pathconf =		VOP_EBADF,	/* per pathconf(2) */
69	.vop_poll =		dead_poll,
70	.vop_read =		dead_read,
71	.vop_readdir =		VOP_EBADF,
72	.vop_readlink =		VOP_EBADF,
73	.vop_reclaim =		VOP_NULL,
74	.vop_remove =		VOP_PANIC,
75	.vop_rename =		dead_rename,
76	.vop_rmdir =		VOP_PANIC,
77	.vop_setattr =		VOP_EBADF,
78	.vop_symlink =		VOP_PANIC,
79	.vop_vptocnp =		VOP_EBADF,
80	.vop_unset_text =	dead_unset_text,
81	.vop_write =		dead_write,
82};
83
84static int
85dead_getwritemount(struct vop_getwritemount_args *ap)
86{
87
88	*(ap->a_mpp) = NULL;
89	return (0);
90}
91
92/*
93 * Trivial lookup routine that always fails.
94 */
95static int
96dead_lookup(struct vop_lookup_args *ap)
97{
98
99	*ap->a_vpp = NULL;
100	return (ENOTDIR);
101}
102
103/*
104 * Open always fails as if device did not exist.
105 */
106static int
107dead_open(struct vop_open_args *ap)
108{
109
110	return (ENXIO);
111}
112
113int
114dead_read(struct vop_read_args *ap)
115{
116
117	/*
118	 * Return EOF for tty devices, EIO for others
119	 */
120	if ((ap->a_vp->v_vflag & VV_ISTTY) == 0)
121		return (EIO);
122	return (0);
123}
124
125int
126dead_write(struct vop_write_args *ap)
127{
128
129	return (EIO);
130}
131
132int
133dead_poll(struct vop_poll_args *ap)
134{
135
136	if (ap->a_events & ~POLLSTANDARD)
137		return (POLLNVAL);
138
139	/*
140	 * Let the user find out that the descriptor is gone.
141	 */
142	return (POLLHUP | ((POLLIN | POLLRDNORM) & ap->a_events));
143
144}
145
146static int
147dead_rename(struct vop_rename_args *ap)
148{
149
150	vop_rename_fail(ap);
151	return (EXDEV);
152}
153
154static int
155dead_unset_text(struct vop_unset_text_args *ap)
156{
157
158	return (0);
159}
160