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_bmap_t dead_bmap; 45 static vop_ioctl_t dead_ioctl; 46 static vop_lock_t dead_lock; 47 static vop_lookup_t dead_lookup; 48 static vop_open_t dead_open; 49 static vop_poll_t dead_poll; 50 static vop_read_t dead_read; 51 static vop_write_t dead_write; 52 53 struct vop_vector dead_vnodeops = { 54 .vop_default = &default_vnodeops, 55 56 .vop_access = VOP_EBADF, 57 .vop_advlock = VOP_EBADF, 58 .vop_bmap = dead_bmap, 59 .vop_create = VOP_PANIC, 60 .vop_getattr = VOP_EBADF, 61 .vop_inactive = VOP_NULL, 62 .vop_ioctl = dead_ioctl, 63 .vop_link = VOP_PANIC, 64 .vop_lock = dead_lock, 65 .vop_lookup = dead_lookup, 66 .vop_mkdir = VOP_PANIC, 67 .vop_mknod = VOP_PANIC, 68 .vop_open = dead_open, 69 .vop_pathconf = VOP_EBADF, /* per pathconf(2) */ 70 .vop_poll = dead_poll, 71 .vop_read = dead_read, 72 .vop_readdir = VOP_EBADF, 73 .vop_readlink = VOP_EBADF, 74 .vop_reclaim = VOP_NULL, 75 .vop_remove = VOP_PANIC, 76 .vop_rename = VOP_PANIC, 77 .vop_rmdir = VOP_PANIC, 78 .vop_setattr = VOP_EBADF, 79 .vop_symlink = VOP_PANIC, 80 .vop_write = dead_write, 81 }; 82 83 /* 84 * Trivial lookup routine that always fails. 85 */ 86 /* ARGSUSED */ 87 static int 88 dead_lookup(ap) 89 struct vop_lookup_args /* { 90 struct vnode * a_dvp; 91 struct vnode ** a_vpp; 92 struct componentname * a_cnp; 93 } */ *ap; 94 { 95 96 *ap->a_vpp = NULL; 97 return (ENOTDIR); 98 } 99 100 /* 101 * Open always fails as if device did not exist. 102 */ 103 /* ARGSUSED */ 104 static int 105 dead_open(ap) 106 struct vop_open_args /* { 107 struct vnode *a_vp; 108 int a_mode; 109 struct ucred *a_cred; 110 struct proc *a_p; 111 } */ *ap; 112 { 113 114 return (ENXIO); 115 } 116 117 /* 118 * Vnode op for read 119 */ 120 /* ARGSUSED */ 121 static int 122 dead_read(ap) 123 struct vop_read_args /* { 124 struct vnode *a_vp; 125 struct uio *a_uio; 126 int a_ioflag; 127 struct ucred *a_cred; 128 } */ *ap; 129 { 130 131 if (vx_wait(ap->a_vp)) 132 panic("dead_read: lock"); 133 /* 134 * Return EOF for tty devices, EIO for others 135 */ 136 if ((ap->a_vp->v_vflag & VV_ISTTY) == 0) 137 return (EIO); 138 return (0); 139 } 140 141 /* 142 * Vnode op for write 143 */ 144 /* ARGSUSED */ 145 static int 146 dead_write(ap) 147 struct vop_write_args /* { 148 struct vnode *a_vp; 149 struct uio *a_uio; 150 int a_ioflag; 151 struct ucred *a_cred; 152 } */ *ap; 153 { 154 155 if (vx_wait(ap->a_vp)) 156 panic("dead_write: lock"); 157 return (EIO); 158 } 159 160 /* 161 * Device ioctl operation. 162 */ 163 /* ARGSUSED */ 164 static int 165 dead_ioctl(ap) 166 struct vop_ioctl_args /* { 167 struct vnode *a_vp; 168 u_long a_command; 169 caddr_t a_data; 170 int a_fflag; 171 struct ucred *a_cred; 172 struct proc *a_p; 173 } */ *ap; 174 { 175 176 if (!vx_wait(ap->a_vp)) 177 return (ENOTTY); 178 /* XXX: Doesn't this just recurse back here ? */ 179 return (VOP_IOCTL_AP(ap)); 180 } 181 182 183 /* 184 * Wait until the vnode has finished changing state. 185 */ 186 static int 187 dead_lock(ap) 188 struct vop_lock_args /* { 189 struct vnode *a_vp; 190 int a_flags; 191 struct proc *a_p; 192 } */ *ap; 193 { 194 struct vnode *vp = ap->a_vp; 195 196 /* 197 * Since we are not using the lock manager, we must clear 198 * the interlock here. 199 */ 200 if (ap->a_flags & LK_INTERLOCK) { 201 mtx_unlock(&vp->v_interlock); 202 ap->a_flags &= ~LK_INTERLOCK; 203 } 204 if (!vx_wait(vp)) 205 return (0); 206 return (VOP_LOCK_AP(ap)); 207 } 208 209 /* 210 * Wait until the vnode has finished changing state. 211 */ 212 static int 213 dead_bmap(ap) 214 struct vop_bmap_args /* { 215 struct vnode *a_vp; 216 daddr_t a_bn; 217 struct bufobj **a_bop; 218 daddr_t *a_bnp; 219 int *a_runp; 220 int *a_runb; 221 } */ *ap; 222 { 223 224 if (!vx_wait(ap->a_vp)) 225 return (EIO); 226 return (VOP_BMAP(ap->a_vp, ap->a_bn, ap->a_bop, ap->a_bnp, ap->a_runp, ap->a_runb)); 227 } 228 229 /* 230 * Trivial poll routine that always returns POLLHUP. 231 * This is necessary so that a process which is polling a file 232 * gets notified when that file is revoke()d. 233 */ 234 static int 235 dead_poll(ap) 236 struct vop_poll_args *ap; 237 { 238 return (POLLHUP); 239 } 240