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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)dead_vnops.c 8.1 (Berkeley) 6/10/93 34 * $FreeBSD: src/sys/miscfs/deadfs/dead_vnops.c,v 1.26 1999/08/28 00:46:42 peter Exp $ 35 * $DragonFly: src/sys/vfs/deadfs/dead_vnops.c,v 1.20 2007/08/13 17:31:56 dillon Exp $ 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/kernel.h> 41 #include <sys/lock.h> 42 #include <sys/vnode.h> 43 #include <sys/fcntl.h> 44 #include <sys/buf.h> 45 46 /* 47 * Prototypes for dead operations on vnodes. 48 */ 49 static int dead_badop (void); 50 static int dead_bmap (struct vop_bmap_args *); 51 static int dead_ioctl (struct vop_ioctl_args *); 52 static int dead_lookup (struct vop_old_lookup_args *); 53 static int dead_open (struct vop_open_args *); 54 static int dead_close (struct vop_close_args *); 55 static int dead_print (struct vop_print_args *); 56 static int dead_read (struct vop_read_args *); 57 static int dead_write (struct vop_write_args *); 58 59 struct vop_ops dead_vnode_vops = { 60 .vop_default = vop_defaultop, 61 .vop_access = (void *)vop_ebadf, 62 .vop_advlock = (void *)vop_ebadf, 63 .vop_bmap = dead_bmap, 64 .vop_old_create = (void *)dead_badop, 65 .vop_getattr = (void *)vop_ebadf, 66 .vop_inactive = (void *)vop_null, 67 .vop_ioctl = dead_ioctl, 68 .vop_old_link = (void *)dead_badop, 69 .vop_old_lookup = dead_lookup, 70 .vop_old_mkdir = (void *)dead_badop, 71 .vop_old_mknod = (void *)dead_badop, 72 .vop_mmap = (void *)dead_badop, 73 .vop_open = dead_open, 74 .vop_close = dead_close, 75 .vop_pathconf = (void *)vop_ebadf, /* per pathconf(2) */ 76 .vop_print = dead_print, 77 .vop_read = dead_read, 78 .vop_readdir = (void *)vop_ebadf, 79 .vop_readlink = (void *)vop_ebadf, 80 .vop_reclaim = (void *)vop_null, 81 .vop_old_remove = (void *)dead_badop, 82 .vop_old_rename = (void *)dead_badop, 83 .vop_old_rmdir = (void *)dead_badop, 84 .vop_setattr = (void *)vop_ebadf, 85 .vop_old_symlink = (void *)dead_badop, 86 .vop_write = dead_write 87 }; 88 89 struct vop_ops *dead_vnode_vops_p = &dead_vnode_vops; 90 91 VNODEOP_SET(dead_vnode_vops); 92 93 /* 94 * Trivial lookup routine that always fails. 95 * 96 * dead_lookup(struct vnode *a_dvp, struct vnode **a_vpp, 97 * struct componentname *a_cnp) 98 */ 99 /* ARGSUSED */ 100 static int 101 dead_lookup(struct vop_old_lookup_args *ap) 102 { 103 *ap->a_vpp = NULL; 104 return (ENOTDIR); 105 } 106 107 /* 108 * Open always fails as if device did not exist. 109 * 110 * dead_open(struct vnode *a_vp, int a_mode, struct ucred *a_cred, 111 * struct proc *a_p) 112 */ 113 /* ARGSUSED */ 114 static int 115 dead_open(struct vop_open_args *ap) 116 { 117 return (ENXIO); 118 } 119 120 /* 121 * Close always succeeds, and does not warn or panic if v_opencount or 122 * v_writecount is incorrect, because a forced unmount or revocation 123 * might have closed the file out from under the descriptor. 124 */ 125 static int 126 dead_close(struct vop_close_args *ap) 127 { 128 struct vnode *vp = ap->a_vp; 129 130 if (vp->v_opencount > 0) { 131 if ((ap->a_fflag & FWRITE) && vp->v_writecount > 0) 132 --vp->v_writecount; 133 --vp->v_opencount; 134 } 135 return (0); 136 } 137 138 /* 139 * Vnode op for read 140 * 141 * dead_read(struct vnode *a_vp, struct uio *a_uio, int a_ioflag, 142 * struct ucred *a_cred) 143 */ 144 /* ARGSUSED */ 145 static int 146 dead_read(struct vop_read_args *ap) 147 { 148 /* 149 * Return EOF for tty devices, EIO for others 150 */ 151 if ((ap->a_vp->v_flag & VISTTY) == 0) 152 return (EIO); 153 return (0); 154 } 155 156 /* 157 * Vnode op for write 158 * 159 * dead_write(struct vnode *a_vp, struct uio *a_uio, int a_ioflag, 160 * struct ucred *a_cred) 161 */ 162 /* ARGSUSED */ 163 static int 164 dead_write(struct vop_write_args *ap) 165 { 166 return (EIO); 167 } 168 169 /* 170 * Device ioctl operation. 171 * 172 * dead_ioctl(struct vnode *a_vp, int a_command, caddr_t a_data, int a_fflag, 173 * struct ucred *a_cred, struct proc *a_p) 174 */ 175 /* ARGSUSED */ 176 static int 177 dead_ioctl(struct vop_ioctl_args *ap) 178 { 179 return (ENOTTY); 180 } 181 182 /* 183 * Wait until the vnode has finished changing state. 184 * 185 * dead_bmap(struct vnode *a_vp, off_t a_loffset, 186 * off_t *a_doffsetp, int *a_runp, int *a_runb) 187 */ 188 static int 189 dead_bmap(struct vop_bmap_args *ap) 190 { 191 return (EIO); 192 } 193 194 /* 195 * Print out the contents of a dead vnode. 196 * 197 * dead_print(struct vnode *a_vp) 198 */ 199 /* ARGSUSED */ 200 static int 201 dead_print(struct vop_print_args *ap) 202 { 203 kprintf("tag VT_NON, dead vnode\n"); 204 return (0); 205 } 206 207 /* 208 * Empty vnode bad operation 209 */ 210 static int 211 dead_badop(void) 212 { 213 panic("dead_badop called"); 214 /* NOTREACHED */ 215 } 216