1 /* $NetBSD: dead_vnops.c,v 1.21 1996/10/13 02:21:25 christos Exp $ */ 2 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. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)dead_vnops.c 8.2 (Berkeley) 11/21/94 36 */ 37 38 #include <sys/param.h> 39 #include <sys/systm.h> 40 #include <sys/time.h> 41 #include <sys/vnode.h> 42 #include <sys/errno.h> 43 #include <sys/namei.h> 44 #include <sys/buf.h> 45 #include <sys/proc.h> 46 47 #include <miscfs/genfs/genfs.h> 48 49 /* 50 * Prototypes for dead operations on vnodes. 51 */ 52 int dead_lookup __P((void *)); 53 #define dead_create genfs_badop 54 #define dead_mknod genfs_badop 55 int dead_open __P((void *)); 56 #define dead_close genfs_nullop 57 #define dead_access genfs_ebadf 58 #define dead_getattr genfs_ebadf 59 #define dead_setattr genfs_ebadf 60 int dead_read __P((void *)); 61 int dead_write __P((void *)); 62 int dead_ioctl __P((void *)); 63 int dead_poll __P((void *)); 64 #define dead_mmap genfs_badop 65 #define dead_fsync genfs_nullop 66 #define dead_seek genfs_nullop 67 #define dead_remove genfs_badop 68 #define dead_link genfs_badop 69 #define dead_rename genfs_badop 70 #define dead_mkdir genfs_badop 71 #define dead_rmdir genfs_badop 72 #define dead_symlink genfs_badop 73 #define dead_readdir genfs_ebadf 74 #define dead_readlink genfs_ebadf 75 #define dead_abortop genfs_badop 76 #define dead_inactive genfs_nullop 77 #define dead_reclaim genfs_nullop 78 int dead_lock __P((void *)); 79 #define dead_unlock genfs_nullop 80 int dead_bmap __P((void *)); 81 int dead_strategy __P((void *)); 82 int dead_print __P((void *)); 83 #define dead_islocked genfs_nullop 84 #define dead_pathconf genfs_ebadf 85 #define dead_advlock genfs_ebadf 86 #define dead_blkatoff genfs_badop 87 #define dead_valloc genfs_badop 88 #define dead_vfree genfs_badop 89 #define dead_truncate genfs_nullop 90 #define dead_update genfs_nullop 91 #define dead_bwrite genfs_nullop 92 93 int chkvnlock __P((struct vnode *)); 94 95 int (**dead_vnodeop_p) __P((void *)); 96 97 struct vnodeopv_entry_desc dead_vnodeop_entries[] = { 98 { &vop_default_desc, vn_default_error }, 99 { &vop_lookup_desc, dead_lookup }, /* lookup */ 100 { &vop_create_desc, dead_create }, /* create */ 101 { &vop_mknod_desc, dead_mknod }, /* mknod */ 102 { &vop_open_desc, dead_open }, /* open */ 103 { &vop_close_desc, dead_close }, /* close */ 104 { &vop_access_desc, dead_access }, /* access */ 105 { &vop_getattr_desc, dead_getattr }, /* getattr */ 106 { &vop_setattr_desc, dead_setattr }, /* setattr */ 107 { &vop_read_desc, dead_read }, /* read */ 108 { &vop_write_desc, dead_write }, /* write */ 109 { &vop_ioctl_desc, dead_ioctl }, /* ioctl */ 110 { &vop_poll_desc, dead_poll }, /* poll */ 111 { &vop_mmap_desc, dead_mmap }, /* mmap */ 112 { &vop_fsync_desc, dead_fsync }, /* fsync */ 113 { &vop_seek_desc, dead_seek }, /* seek */ 114 { &vop_remove_desc, dead_remove }, /* remove */ 115 { &vop_link_desc, dead_link }, /* link */ 116 { &vop_rename_desc, dead_rename }, /* rename */ 117 { &vop_mkdir_desc, dead_mkdir }, /* mkdir */ 118 { &vop_rmdir_desc, dead_rmdir }, /* rmdir */ 119 { &vop_symlink_desc, dead_symlink }, /* symlink */ 120 { &vop_readdir_desc, dead_readdir }, /* readdir */ 121 { &vop_readlink_desc, dead_readlink }, /* readlink */ 122 { &vop_abortop_desc, dead_abortop }, /* abortop */ 123 { &vop_inactive_desc, dead_inactive }, /* inactive */ 124 { &vop_reclaim_desc, dead_reclaim }, /* reclaim */ 125 { &vop_lock_desc, dead_lock }, /* lock */ 126 { &vop_unlock_desc, dead_unlock }, /* unlock */ 127 { &vop_bmap_desc, dead_bmap }, /* bmap */ 128 { &vop_strategy_desc, dead_strategy }, /* strategy */ 129 { &vop_print_desc, dead_print }, /* print */ 130 { &vop_islocked_desc, dead_islocked }, /* islocked */ 131 { &vop_pathconf_desc, dead_pathconf }, /* pathconf */ 132 { &vop_advlock_desc, dead_advlock }, /* advlock */ 133 { &vop_blkatoff_desc, dead_blkatoff }, /* blkatoff */ 134 { &vop_valloc_desc, dead_valloc }, /* valloc */ 135 { &vop_vfree_desc, dead_vfree }, /* vfree */ 136 { &vop_truncate_desc, dead_truncate }, /* truncate */ 137 { &vop_update_desc, dead_update }, /* update */ 138 { &vop_bwrite_desc, dead_bwrite }, /* bwrite */ 139 { (struct vnodeop_desc*)NULL, (int(*) __P((void *)))NULL } 140 }; 141 struct vnodeopv_desc dead_vnodeop_opv_desc = 142 { &dead_vnodeop_p, dead_vnodeop_entries }; 143 144 /* 145 * Trivial lookup routine that always fails. 146 */ 147 /* ARGSUSED */ 148 int 149 dead_lookup(v) 150 void *v; 151 { 152 struct vop_lookup_args /* { 153 struct vnode * a_dvp; 154 struct vnode ** a_vpp; 155 struct componentname * a_cnp; 156 } */ *ap = v; 157 158 *ap->a_vpp = NULL; 159 return (ENOTDIR); 160 } 161 162 /* 163 * Open always fails as if device did not exist. 164 */ 165 /* ARGSUSED */ 166 int 167 dead_open(v) 168 void *v; 169 { 170 171 return (ENXIO); 172 } 173 174 /* 175 * Vnode op for read 176 */ 177 /* ARGSUSED */ 178 int 179 dead_read(v) 180 void *v; 181 { 182 struct vop_read_args /* { 183 struct vnode *a_vp; 184 struct uio *a_uio; 185 int a_ioflag; 186 struct ucred *a_cred; 187 } */ *ap = v; 188 189 if (chkvnlock(ap->a_vp)) 190 panic("dead_read: lock"); 191 /* 192 * Return EOF for tty devices, EIO for others 193 */ 194 if ((ap->a_vp->v_flag & VISTTY) == 0) 195 return (EIO); 196 return (0); 197 } 198 199 /* 200 * Vnode op for write 201 */ 202 /* ARGSUSED */ 203 int 204 dead_write(v) 205 void *v; 206 { 207 struct vop_write_args /* { 208 struct vnode *a_vp; 209 struct uio *a_uio; 210 int a_ioflag; 211 struct ucred *a_cred; 212 } */ *ap = v; 213 214 if (chkvnlock(ap->a_vp)) 215 panic("dead_write: lock"); 216 return (EIO); 217 } 218 219 /* 220 * Device ioctl operation. 221 */ 222 /* ARGSUSED */ 223 int 224 dead_ioctl(v) 225 void *v; 226 { 227 struct vop_ioctl_args /* { 228 struct vnode *a_vp; 229 u_long a_command; 230 caddr_t a_data; 231 int a_fflag; 232 struct ucred *a_cred; 233 struct proc *a_p; 234 } */ *ap = v; 235 236 if (!chkvnlock(ap->a_vp)) 237 return (EBADF); 238 return (VCALL(ap->a_vp, VOFFSET(vop_ioctl), ap)); 239 } 240 241 /* ARGSUSED */ 242 int 243 dead_poll(v) 244 void *v; 245 { 246 struct vop_poll_args /* { 247 struct vnode *a_vp; 248 int a_events; 249 struct proc *a_p; 250 } */ *ap = v; 251 252 /* 253 * Let the user find out that the descriptor is gone. 254 */ 255 return (ap->a_events); 256 } 257 258 /* 259 * Just call the device strategy routine 260 */ 261 int 262 dead_strategy(v) 263 void *v; 264 { 265 266 struct vop_strategy_args /* { 267 struct buf *a_bp; 268 } */ *ap = v; 269 if (ap->a_bp->b_vp == NULL || !chkvnlock(ap->a_bp->b_vp)) { 270 ap->a_bp->b_flags |= B_ERROR; 271 biodone(ap->a_bp); 272 return (EIO); 273 } 274 return (VOP_STRATEGY(ap->a_bp)); 275 } 276 277 /* 278 * Wait until the vnode has finished changing state. 279 */ 280 int 281 dead_lock(v) 282 void *v; 283 { 284 struct vop_lock_args /* { 285 struct vnode *a_vp; 286 } */ *ap = v; 287 288 if (!chkvnlock(ap->a_vp)) 289 return (0); 290 return (VCALL(ap->a_vp, VOFFSET(vop_lock), ap)); 291 } 292 293 /* 294 * Wait until the vnode has finished changing state. 295 */ 296 int 297 dead_bmap(v) 298 void *v; 299 { 300 struct vop_bmap_args /* { 301 struct vnode *a_vp; 302 daddr_t a_bn; 303 struct vnode **a_vpp; 304 daddr_t *a_bnp; 305 int *a_runp; 306 } */ *ap = v; 307 308 if (!chkvnlock(ap->a_vp)) 309 return (EIO); 310 return (VOP_BMAP(ap->a_vp, ap->a_bn, ap->a_vpp, ap->a_bnp, ap->a_runp)); 311 } 312 313 /* 314 * Print out the contents of a dead vnode. 315 */ 316 /* ARGSUSED */ 317 int 318 dead_print(v) 319 void *v; 320 { 321 printf("tag VT_NON, dead vnode\n"); 322 return 0; 323 } 324 325 /* 326 * We have to wait during times when the vnode is 327 * in a state of change. 328 */ 329 int 330 chkvnlock(vp) 331 register struct vnode *vp; 332 { 333 int locked = 0; 334 335 while (vp->v_flag & VXLOCK) { 336 vp->v_flag |= VXWANT; 337 sleep((caddr_t)vp, PINOD); 338 locked = 1; 339 } 340 return (locked); 341 } 342