1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 4. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)dead_vnops.c 8.1 (Berkeley) 6/10/93 30 * $FreeBSD$ 31 */ 32 33 #include <sys/param.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/lock.h> 37 #include <sys/mutex.h> 38 #include <sys/poll.h> 39 #include <sys/vnode.h> 40 41 /* 42 * Prototypes for dead operations on vnodes. 43 */ 44 static vop_lookup_t dead_lookup; 45 static vop_open_t dead_open; 46 static vop_poll_t dead_poll; 47 static vop_read_t dead_read; 48 static vop_write_t dead_write; 49 static vop_getwritemount_t dead_getwritemount; 50 static vop_rename_t dead_rename; 51 52 struct 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_write = dead_write, 81 }; 82 83 /* ARGSUSED */ 84 static int 85 dead_getwritemount(ap) 86 struct vop_getwritemount_args /* { 87 struct vnode *a_vp; 88 struct mount **a_mpp; 89 } */ *ap; 90 { 91 *(ap->a_mpp) = NULL; 92 return (0); 93 } 94 95 /* 96 * Trivial lookup routine that always fails. 97 */ 98 /* ARGSUSED */ 99 static int 100 dead_lookup(ap) 101 struct vop_lookup_args /* { 102 struct vnode * a_dvp; 103 struct vnode ** a_vpp; 104 struct componentname * a_cnp; 105 } */ *ap; 106 { 107 108 *ap->a_vpp = NULL; 109 return (ENOTDIR); 110 } 111 112 /* 113 * Open always fails as if device did not exist. 114 */ 115 /* ARGSUSED */ 116 static int 117 dead_open(ap) 118 struct vop_open_args /* { 119 struct vnode *a_vp; 120 int a_mode; 121 struct ucred *a_cred; 122 struct proc *a_p; 123 } */ *ap; 124 { 125 126 return (ENXIO); 127 } 128 129 /* 130 * Vnode op for read 131 */ 132 /* ARGSUSED */ 133 static int 134 dead_read(ap) 135 struct vop_read_args /* { 136 struct vnode *a_vp; 137 struct uio *a_uio; 138 int a_ioflag; 139 struct ucred *a_cred; 140 } */ *ap; 141 { 142 /* 143 * Return EOF for tty devices, EIO for others 144 */ 145 if ((ap->a_vp->v_vflag & VV_ISTTY) == 0) 146 return (EIO); 147 return (0); 148 } 149 150 /* 151 * Vnode op for write 152 */ 153 /* ARGSUSED */ 154 static int 155 dead_write(ap) 156 struct vop_write_args /* { 157 struct vnode *a_vp; 158 struct uio *a_uio; 159 int a_ioflag; 160 struct ucred *a_cred; 161 } */ *ap; 162 { 163 return (EIO); 164 } 165 166 /* 167 * Trivial poll routine that always returns POLLHUP. 168 * This is necessary so that a process which is polling a file 169 * gets notified when that file is revoke()d. 170 */ 171 static int 172 dead_poll(ap) 173 struct vop_poll_args *ap; 174 { 175 return (POLLHUP); 176 } 177 178 static int 179 dead_rename(ap) 180 struct vop_rename_args /* { 181 struct vnode *a_fdvp; 182 struct vnode *a_fvp; 183 struct componentname *a_fcnp; 184 struct vnode *a_tdvp; 185 struct vnode *a_tvp; 186 struct componentname *a_tcnp; 187 } */ *ap; 188 { 189 190 vop_rename_fail(ap); 191 return (EXDEV); 192 } 193