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
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/lock.h>
36 #include <sys/mutex.h>
37 #include <sys/poll.h>
38 #include <sys/vnode.h>
39
40 /*
41 * Prototypes for dead operations on vnodes.
42 */
43 static vop_lookup_t dead_lookup;
44 static vop_open_t dead_open;
45 static vop_close_t dead_close;
46 static vop_getwritemount_t dead_getwritemount;
47 static vop_rename_t dead_rename;
48 static vop_unset_text_t dead_unset_text;
49
50 struct vop_vector dead_vnodeops = {
51 .vop_default = &default_vnodeops,
52
53 .vop_access = VOP_EBADF,
54 .vop_advlock = VOP_EBADF,
55 .vop_bmap = VOP_EBADF,
56 .vop_close = dead_close,
57 .vop_create = VOP_PANIC,
58 .vop_getattr = VOP_EBADF,
59 .vop_getwritemount = dead_getwritemount,
60 .vop_inactive = VOP_NULL,
61 .vop_ioctl = VOP_EBADF,
62 .vop_link = VOP_PANIC,
63 .vop_lookup = dead_lookup,
64 .vop_mkdir = VOP_PANIC,
65 .vop_mknod = VOP_PANIC,
66 .vop_open = dead_open,
67 .vop_pathconf = VOP_EBADF, /* per pathconf(2) */
68 .vop_poll = dead_poll,
69 .vop_read = dead_read,
70 .vop_readdir = VOP_EBADF,
71 .vop_readlink = VOP_EBADF,
72 .vop_reclaim = VOP_NULL,
73 .vop_remove = VOP_PANIC,
74 .vop_rename = dead_rename,
75 .vop_rmdir = VOP_PANIC,
76 .vop_setattr = VOP_EBADF,
77 .vop_symlink = VOP_PANIC,
78 .vop_vptocnp = VOP_EBADF,
79 .vop_unset_text = dead_unset_text,
80 .vop_write = dead_write,
81 .vop_fplookup_vexec = VOP_EOPNOTSUPP,
82 .vop_fplookup_symlink = VOP_EOPNOTSUPP,
83 };
84 VFS_VOP_VECTOR_REGISTER(dead_vnodeops);
85
86 static int
dead_getwritemount(struct vop_getwritemount_args * ap)87 dead_getwritemount(struct vop_getwritemount_args *ap)
88 {
89
90 *(ap->a_mpp) = NULL;
91 return (0);
92 }
93
94 /*
95 * Trivial lookup routine that always fails.
96 */
97 static int
dead_lookup(struct vop_lookup_args * ap)98 dead_lookup(struct vop_lookup_args *ap)
99 {
100
101 *ap->a_vpp = NULL;
102 return (ENOTDIR);
103 }
104
105 /*
106 * Silently succeed open and close.
107 */
108 static int
dead_open(struct vop_open_args * ap)109 dead_open(struct vop_open_args *ap)
110 {
111 return (0);
112 }
113
114 static int
dead_close(struct vop_close_args * ap)115 dead_close(struct vop_close_args *ap)
116 {
117 return (0);
118 }
119
120 int
dead_read(struct vop_read_args * ap)121 dead_read(struct vop_read_args *ap)
122 {
123
124 /*
125 * Return EOF for tty devices, EIO for others
126 */
127 if ((ap->a_vp->v_vflag & VV_ISTTY) == 0)
128 return (EIO);
129 return (0);
130 }
131
132 int
dead_write(struct vop_write_args * ap)133 dead_write(struct vop_write_args *ap)
134 {
135
136 return (EIO);
137 }
138
139 int
dead_poll(struct vop_poll_args * ap)140 dead_poll(struct vop_poll_args *ap)
141 {
142
143 if (ap->a_events & ~POLLSTANDARD)
144 return (POLLNVAL);
145
146 /*
147 * Let the user find out that the descriptor is gone.
148 */
149 return (POLLHUP | ((POLLIN | POLLRDNORM) & ap->a_events));
150
151 }
152
153 static int
dead_rename(struct vop_rename_args * ap)154 dead_rename(struct vop_rename_args *ap)
155 {
156
157 vop_rename_fail(ap);
158 return (EXDEV);
159 }
160
161 static int
dead_unset_text(struct vop_unset_text_args * ap)162 dead_unset_text(struct vop_unset_text_args *ap)
163 {
164
165 return (0);
166 }
167