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 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 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 109 dead_open(struct vop_open_args *ap) 110 { 111 return (0); 112 } 113 114 static int 115 dead_close(struct vop_close_args *ap) 116 { 117 return (0); 118 } 119 120 int 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 133 dead_write(struct vop_write_args *ap) 134 { 135 136 return (EIO); 137 } 138 139 int 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 154 dead_rename(struct vop_rename_args *ap) 155 { 156 157 vop_rename_fail(ap); 158 return (EXDEV); 159 } 160 161 static int 162 dead_unset_text(struct vop_unset_text_args *ap) 163 { 164 165 return (0); 166 } 167