layer_subr.c revision 1.3.2.2
1 1.3.2.2 thorpej /* $NetBSD: layer_subr.c,v 1.3.2.2 1999/08/02 22:27:34 thorpej Exp $ */ 2 1.3.2.2 thorpej 3 1.3.2.2 thorpej /* 4 1.3.2.2 thorpej * Copyright (c) 1999 National Aeronautics & Space Administration 5 1.3.2.2 thorpej * All rights reserved. 6 1.3.2.2 thorpej * 7 1.3.2.2 thorpej * This software was written by William Studenmund of the 8 1.3.2.2 thorpej * Numerical Aerospace Similation Facility, NASA Ames Research Center. 9 1.3.2.2 thorpej * 10 1.3.2.2 thorpej * Redistribution and use in source and binary forms, with or without 11 1.3.2.2 thorpej * modification, are permitted provided that the following conditions 12 1.3.2.2 thorpej * are met: 13 1.3.2.2 thorpej * 1. Redistributions of source code must retain the above copyright 14 1.3.2.2 thorpej * notice, this list of conditions and the following disclaimer. 15 1.3.2.2 thorpej * 2. Redistributions in binary form must reproduce the above copyright 16 1.3.2.2 thorpej * notice, this list of conditions and the following disclaimer in the 17 1.3.2.2 thorpej * documentation and/or other materials provided with the distribution. 18 1.3.2.2 thorpej * 3. Neither the the name of the National Aeronautics & Space Administration 19 1.3.2.2 thorpej * nor the names of its contributors may be used to endorse or promote 20 1.3.2.2 thorpej * products derived from this software without specific prior written 21 1.3.2.2 thorpej * permission. 22 1.3.2.2 thorpej * 23 1.3.2.2 thorpej * THIS SOFTWARE IS PROVIDED BY THE NATIONAL AERONAUTICS & SPACE ADMINISTRATION 24 1.3.2.2 thorpej * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 25 1.3.2.2 thorpej * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 26 1.3.2.2 thorpej * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE ADMINISTRATION OR CONTRIB- 27 1.3.2.2 thorpej * UTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 28 1.3.2.2 thorpej * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 29 1.3.2.2 thorpej * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 30 1.3.2.2 thorpej * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 31 1.3.2.2 thorpej * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 32 1.3.2.2 thorpej * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 1.3.2.2 thorpej * POSSIBILITY OF SUCH DAMAGE. 34 1.3.2.2 thorpej */ 35 1.3.2.2 thorpej /* 36 1.3.2.2 thorpej * Copyright (c) 1992, 1993 37 1.3.2.2 thorpej * The Regents of the University of California. All rights reserved. 38 1.3.2.2 thorpej * 39 1.3.2.2 thorpej * This code is derived from software donated to Berkeley by 40 1.3.2.2 thorpej * Jan-Simon Pendry. 41 1.3.2.2 thorpej * 42 1.3.2.2 thorpej * Redistribution and use in source and binary forms, with or without 43 1.3.2.2 thorpej * modification, are permitted provided that the following conditions 44 1.3.2.2 thorpej * are met: 45 1.3.2.2 thorpej * 1. Redistributions of source code must retain the above copyright 46 1.3.2.2 thorpej * notice, this list of conditions and the following disclaimer. 47 1.3.2.2 thorpej * 2. Redistributions in binary form must reproduce the above copyright 48 1.3.2.2 thorpej * notice, this list of conditions and the following disclaimer in the 49 1.3.2.2 thorpej * documentation and/or other materials provided with the distribution. 50 1.3.2.2 thorpej * 3. All advertising materials mentioning features or use of this software 51 1.3.2.2 thorpej * must display the following acknowledgement: 52 1.3.2.2 thorpej * This product includes software developed by the University of 53 1.3.2.2 thorpej * California, Berkeley and its contributors. 54 1.3.2.2 thorpej * 4. Neither the name of the University nor the names of its contributors 55 1.3.2.2 thorpej * may be used to endorse or promote products derived from this software 56 1.3.2.2 thorpej * without specific prior written permission. 57 1.3.2.2 thorpej * 58 1.3.2.2 thorpej * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 59 1.3.2.2 thorpej * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 60 1.3.2.2 thorpej * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 61 1.3.2.2 thorpej * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 62 1.3.2.2 thorpej * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 63 1.3.2.2 thorpej * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 64 1.3.2.2 thorpej * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 65 1.3.2.2 thorpej * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 66 1.3.2.2 thorpej * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 67 1.3.2.2 thorpej * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 68 1.3.2.2 thorpej * SUCH DAMAGE. 69 1.3.2.2 thorpej * 70 1.3.2.2 thorpej * from: Id: lofs_subr.c,v 1.11 1992/05/30 10:05:43 jsp Exp 71 1.3.2.2 thorpej * @(#)null_subr.c 8.7 (Berkeley) 5/14/95 72 1.3.2.2 thorpej */ 73 1.3.2.2 thorpej 74 1.3.2.2 thorpej #include <sys/param.h> 75 1.3.2.2 thorpej #include <sys/systm.h> 76 1.3.2.2 thorpej #include <sys/proc.h> 77 1.3.2.2 thorpej #include <sys/time.h> 78 1.3.2.2 thorpej #include <sys/types.h> 79 1.3.2.2 thorpej #include <sys/vnode.h> 80 1.3.2.2 thorpej #include <sys/mount.h> 81 1.3.2.2 thorpej #include <sys/namei.h> 82 1.3.2.2 thorpej #include <sys/malloc.h> 83 1.3.2.2 thorpej #include <miscfs/specfs/specdev.h> 84 1.3.2.2 thorpej #include <miscfs/genfs/layer.h> 85 1.3.2.2 thorpej #include <miscfs/genfs/layer_extern.h> 86 1.3.2.2 thorpej 87 1.3.2.2 thorpej #define NLAYERNODECACHE 16 88 1.3.2.2 thorpej 89 1.3.2.2 thorpej /* 90 1.3.2.2 thorpej * layer cache: 91 1.3.2.2 thorpej * Each cache entry holds a reference to the lower vnode 92 1.3.2.2 thorpej * along with a pointer to the alias vnode. When an 93 1.3.2.2 thorpej * entry is added the lower vnode is VREF'd. When the 94 1.3.2.2 thorpej * alias is removed the lower vnode is vrele'd. 95 1.3.2.2 thorpej */ 96 1.3.2.2 thorpej 97 1.3.2.2 thorpej /* 98 1.3.2.2 thorpej * Initialise cache headers 99 1.3.2.2 thorpej */ 100 1.3.2.2 thorpej void 101 1.3.2.2 thorpej layerfs_init() 102 1.3.2.2 thorpej { 103 1.3.2.2 thorpej 104 1.3.2.2 thorpej #ifdef LAYERFS_DIAGNOSTIC 105 1.3.2.2 thorpej printf("layerfs_init\n"); /* printed during system boot */ 106 1.3.2.2 thorpej #endif 107 1.3.2.2 thorpej } 108 1.3.2.2 thorpej 109 1.3.2.2 thorpej /* 110 1.3.2.2 thorpej * Return a locked, VREF'ed alias for lower vnode if already exists, else 0. 111 1.3.2.2 thorpej */ 112 1.3.2.2 thorpej struct vnode * 113 1.3.2.2 thorpej layer_node_find(mp, lowervp) 114 1.3.2.2 thorpej struct mount *mp; 115 1.3.2.2 thorpej struct vnode *lowervp; 116 1.3.2.2 thorpej { 117 1.3.2.2 thorpej struct layer_mount *lmp = MOUNTTOLAYERMOUNT(mp); 118 1.3.2.2 thorpej struct layer_node_hashhead *hd; 119 1.3.2.2 thorpej struct layer_node *a; 120 1.3.2.2 thorpej struct vnode *vp; 121 1.3.2.2 thorpej 122 1.3.2.2 thorpej /* 123 1.3.2.2 thorpej * Find hash base, and then search the (two-way) linked 124 1.3.2.2 thorpej * list looking for a layer_node structure which is referencing 125 1.3.2.2 thorpej * the lower vnode. If found, the increment the layer_node 126 1.3.2.2 thorpej * reference count (but NOT the lower vnode's VREF counter) 127 1.3.2.2 thorpej * and return the vnode locked. 128 1.3.2.2 thorpej */ 129 1.3.2.2 thorpej hd = LAYER_NHASH(lmp, lowervp); 130 1.3.2.2 thorpej loop: 131 1.3.2.2 thorpej simple_lock(&lmp->layerm_hashlock); 132 1.3.2.2 thorpej for (a = hd->lh_first; a != 0; a = a->layer_hash.le_next) { 133 1.3.2.2 thorpej if (a->layer_lowervp == lowervp && LAYERTOV(a)->v_mount == mp) { 134 1.3.2.2 thorpej vp = LAYERTOV(a); 135 1.3.2.2 thorpej simple_unlock(&lmp->layerm_hashlock); 136 1.3.2.2 thorpej /* 137 1.3.2.2 thorpej * We must be careful here as the fact the lower 138 1.3.2.2 thorpej * vnode is locked will imply vp is locked unless 139 1.3.2.2 thorpej * someone has decided to start vclean'ing either 140 1.3.2.2 thorpej * vp or lowervp. 141 1.3.2.2 thorpej * 142 1.3.2.2 thorpej * So we try for an exclusive, recursive lock 143 1.3.2.2 thorpej * on the upper vnode. If it fails, vcleaning 144 1.3.2.2 thorpej * is in progress (so when we try again, we'll 145 1.3.2.2 thorpej * fail). If it succeeds, we now have double 146 1.3.2.2 thorpej * locked the bottom node. So we do an explicit 147 1.3.2.2 thorpej * VOP_UNLOCK on it to keep the counts right. Note 148 1.3.2.2 thorpej * that we will end up with the upper node and 149 1.3.2.2 thorpej * the lower node locked once. 150 1.3.2.2 thorpej */ 151 1.3.2.2 thorpej if (vget(vp, LK_EXCLUSIVE | LK_CANRECURSE)) { 152 1.3.2.2 thorpej printf ("layer_node_find: vget failed.\n"); 153 1.3.2.2 thorpej goto loop; 154 1.3.2.2 thorpej }; 155 1.3.2.2 thorpej VOP_UNLOCK(lowervp, 0); 156 1.3.2.2 thorpej return (vp); 157 1.3.2.2 thorpej } 158 1.3.2.2 thorpej } 159 1.3.2.2 thorpej 160 1.3.2.2 thorpej simple_unlock(&lmp->layerm_hashlock); 161 1.3.2.2 thorpej return NULL; 162 1.3.2.2 thorpej } 163 1.3.2.2 thorpej 164 1.3.2.2 thorpej 165 1.3.2.2 thorpej /* 166 1.3.2.2 thorpej * Make a new layer_node node. 167 1.3.2.2 thorpej * Vp is the alias vnode, lowervp is the lower vnode. 168 1.3.2.2 thorpej * Maintain a reference to lowervp. 169 1.3.2.2 thorpej */ 170 1.3.2.2 thorpej int 171 1.3.2.2 thorpej layer_node_alloc(mp, lowervp, vpp) 172 1.3.2.2 thorpej struct mount *mp; 173 1.3.2.2 thorpej struct vnode *lowervp; 174 1.3.2.2 thorpej struct vnode **vpp; 175 1.3.2.2 thorpej { 176 1.3.2.2 thorpej struct layer_mount *lmp = MOUNTTOLAYERMOUNT(mp); 177 1.3.2.2 thorpej struct layer_node_hashhead *hd; 178 1.3.2.2 thorpej struct layer_node *xp; 179 1.3.2.2 thorpej struct vnode *vp, *nvp; 180 1.3.2.2 thorpej int error; 181 1.3.2.2 thorpej extern int (**dead_vnodeop_p) __P((void *)); 182 1.3.2.2 thorpej 183 1.3.2.2 thorpej if ((error = getnewvnode(lmp->layerm_tag, mp, lmp->layerm_vnodeop_p, 184 1.3.2.2 thorpej &vp)) != 0) 185 1.3.2.2 thorpej return (error); 186 1.3.2.2 thorpej vp->v_type = lowervp->v_type; 187 1.3.2.2 thorpej vp->v_flag |= VLAYER; 188 1.3.2.2 thorpej 189 1.3.2.2 thorpej MALLOC(xp, struct layer_node *, lmp->layerm_size, M_TEMP, M_WAITOK); 190 1.3.2.2 thorpej if (vp->v_type == VBLK || vp->v_type == VCHR) { 191 1.3.2.2 thorpej MALLOC(vp->v_specinfo, struct specinfo *, 192 1.3.2.2 thorpej sizeof(struct specinfo), M_VNODE, M_WAITOK); 193 1.3.2.2 thorpej vp->v_rdev = lowervp->v_rdev; 194 1.3.2.2 thorpej } 195 1.3.2.2 thorpej 196 1.3.2.2 thorpej vp->v_data = xp; 197 1.3.2.2 thorpej xp->layer_vnode = vp; 198 1.3.2.2 thorpej xp->layer_lowervp = lowervp; 199 1.3.2.2 thorpej xp->layer_flags = 0; 200 1.3.2.2 thorpej /* 201 1.3.2.2 thorpej * Before we insert our new node onto the hash chains, 202 1.3.2.2 thorpej * check to see if someone else has beaten us to it. 203 1.3.2.2 thorpej * (We could have slept in MALLOC.) 204 1.3.2.2 thorpej */ 205 1.3.2.2 thorpej if ((nvp = layer_node_find(mp, lowervp)) != NULL) { 206 1.3.2.2 thorpej *vpp = nvp; 207 1.3.2.2 thorpej 208 1.3.2.2 thorpej /* free the substructures we've allocated. */ 209 1.3.2.2 thorpej FREE(xp, M_TEMP); 210 1.3.2.2 thorpej if (vp->v_type == VBLK || vp->v_type == VCHR) 211 1.3.2.2 thorpej FREE(vp->v_specinfo, M_VNODE); 212 1.3.2.2 thorpej 213 1.3.2.2 thorpej vp->v_type = VBAD; /* node is discarded */ 214 1.3.2.2 thorpej vp->v_op = dead_vnodeop_p; /* so ops will still work */ 215 1.3.2.2 thorpej vrele(vp); /* get rid of it. */ 216 1.3.2.2 thorpej return (0); 217 1.3.2.2 thorpej } 218 1.3.2.2 thorpej 219 1.3.2.2 thorpej simple_lock(&lmp->layerm_hashlock); 220 1.3.2.2 thorpej 221 1.3.2.2 thorpej /* 222 1.3.2.2 thorpej * Now lock the new node. We rely on the fact that we were passed 223 1.3.2.2 thorpej * a locked vnode. If the lower node is exporting a struct lock 224 1.3.2.2 thorpej * (v_vnlock != NULL) then we just set the upper v_vnlock to the 225 1.3.2.2 thorpej * lower one, and both are now locked. If the lower node is exporting 226 1.3.2.2 thorpej * NULL, then we copy that up and manually lock the upper node. 227 1.3.2.2 thorpej * 228 1.3.2.2 thorpej * LAYERFS_UPPERLOCK already has the test, so we use it after copying 229 1.3.2.2 thorpej * up the v_vnlock from below. 230 1.3.2.2 thorpej */ 231 1.3.2.2 thorpej 232 1.3.2.2 thorpej vp->v_vnlock = lowervp->v_vnlock; 233 1.3.2.2 thorpej LAYERFS_UPPERLOCK(vp, LK_EXCLUSIVE, error); 234 1.3.2.2 thorpej 235 1.3.2.2 thorpej if (error) { 236 1.3.2.2 thorpej /* 237 1.3.2.2 thorpej * How did we get a locking error? The node just came off 238 1.3.2.2 thorpej * of the free list, and we're the only routine which 239 1.3.2.2 thorpej * knows it's there... 240 1.3.2.2 thorpej */ 241 1.3.2.2 thorpej vp->v_vnlock = &vp->v_lock; 242 1.3.2.2 thorpej *vpp = NULL; 243 1.3.2.2 thorpej 244 1.3.2.2 thorpej /* free the substructures we've allocated. */ 245 1.3.2.2 thorpej FREE(xp, M_TEMP); 246 1.3.2.2 thorpej if (vp->v_type == VBLK || vp->v_type == VCHR) 247 1.3.2.2 thorpej FREE(vp->v_specinfo, M_VNODE); 248 1.3.2.2 thorpej 249 1.3.2.2 thorpej vp->v_type = VBAD; /* node is discarded */ 250 1.3.2.2 thorpej vp->v_op = dead_vnodeop_p; /* so ops will still work */ 251 1.3.2.2 thorpej vrele(vp); /* get rid of it. */ 252 1.3.2.2 thorpej return (error); 253 1.3.2.2 thorpej } 254 1.3.2.2 thorpej /* 255 1.3.2.2 thorpej * NetBSD used to do an inlined checkalias here. We do not, as 256 1.3.2.2 thorpej * we never flag device nodes as being aliased. The lowervp 257 1.3.2.2 thorpej * node will, when appropriate, be flaged as an alias. 258 1.3.2.2 thorpej */ 259 1.3.2.2 thorpej 260 1.3.2.2 thorpej *vpp = vp; 261 1.3.2.2 thorpej VREF(lowervp); /* Take into account reference held in layer_node */ 262 1.3.2.2 thorpej hd = LAYER_NHASH(lmp, lowervp); 263 1.3.2.2 thorpej LIST_INSERT_HEAD(hd, xp, layer_hash); 264 1.3.2.2 thorpej simple_unlock(&lmp->layerm_hashlock); 265 1.3.2.2 thorpej return (0); 266 1.3.2.2 thorpej } 267 1.3.2.2 thorpej 268 1.3.2.2 thorpej 269 1.3.2.2 thorpej /* 270 1.3.2.2 thorpej * Try to find an existing layer_node vnode refering 271 1.3.2.2 thorpej * to it, otherwise make a new layer_node vnode which 272 1.3.2.2 thorpej * contains a reference to the lower vnode. 273 1.3.2.2 thorpej * 274 1.3.2.2 thorpej * >>> we assume that the lower node is already locked upon entry, so we 275 1.3.2.2 thorpej * propagate the lock state to upper node << 276 1.3.2.2 thorpej */ 277 1.3.2.2 thorpej int 278 1.3.2.2 thorpej layer_node_create(mp, lowervp, newvpp) 279 1.3.2.2 thorpej struct mount *mp; 280 1.3.2.2 thorpej struct vnode *lowervp; 281 1.3.2.2 thorpej struct vnode **newvpp; 282 1.3.2.2 thorpej { 283 1.3.2.2 thorpej struct vnode *aliasvp; 284 1.3.2.2 thorpej struct layer_mount *lmp = MOUNTTOLAYERMOUNT(mp); 285 1.3.2.2 thorpej 286 1.3.2.2 thorpej if ((aliasvp = layer_node_find(mp, lowervp)) != NULL) { 287 1.3.2.2 thorpej /* 288 1.3.2.2 thorpej * layer_node_find has taken another reference 289 1.3.2.2 thorpej * to the alias vnode and moved the lock holding to 290 1.3.2.2 thorpej * aliasvp 291 1.3.2.2 thorpej */ 292 1.3.2.2 thorpej #ifdef LAYERFS_DIAGNOSTIC 293 1.3.2.2 thorpej vprint("layer_node_create: exists", aliasvp); 294 1.3.2.2 thorpej #endif 295 1.3.2.2 thorpej } else { 296 1.3.2.2 thorpej int error; 297 1.3.2.2 thorpej 298 1.3.2.2 thorpej /* 299 1.3.2.2 thorpej * Get new vnode. 300 1.3.2.2 thorpej */ 301 1.3.2.2 thorpej #ifdef LAYERFS_DIAGNOSTIC 302 1.3.2.2 thorpej printf("layer_node_create: create new alias vnode\n"); 303 1.3.2.2 thorpej #endif 304 1.3.2.2 thorpej 305 1.3.2.2 thorpej /* 306 1.3.2.2 thorpej * Make new vnode reference the layer_node. 307 1.3.2.2 thorpej */ 308 1.3.2.2 thorpej if ((error = (lmp->layerm_alloc)(mp, lowervp, &aliasvp)) != 0) 309 1.3.2.2 thorpej return error; 310 1.3.2.2 thorpej 311 1.3.2.2 thorpej /* 312 1.3.2.2 thorpej * aliasvp is already VREF'd by getnewvnode() 313 1.3.2.2 thorpej */ 314 1.3.2.2 thorpej } 315 1.3.2.2 thorpej 316 1.3.2.2 thorpej /* 317 1.3.2.2 thorpej * Now that we have VREF'd the upper vnode, release the reference 318 1.3.2.2 thorpej * to the lower node. The existance of the layer_node retains one 319 1.3.2.2 thorpej * reference to the lower node. 320 1.3.2.2 thorpej */ 321 1.3.2.2 thorpej vrele(lowervp); 322 1.3.2.2 thorpej 323 1.3.2.2 thorpej #ifdef DIAGNOSTIC 324 1.3.2.2 thorpej if (lowervp->v_usecount < 1) { 325 1.3.2.2 thorpej /* Should never happen... */ 326 1.3.2.2 thorpej vprint("layer_node_create: alias", aliasvp); 327 1.3.2.2 thorpej vprint("layer_node_create: lower", lowervp); 328 1.3.2.2 thorpej panic("layer_node_create: lower has 0 usecount."); 329 1.3.2.2 thorpej }; 330 1.3.2.2 thorpej #endif 331 1.3.2.2 thorpej 332 1.3.2.2 thorpej #ifdef LAYERFS_DIAGNOSTIC 333 1.3.2.2 thorpej vprint("layer_node_create: alias", aliasvp); 334 1.3.2.2 thorpej #endif 335 1.3.2.2 thorpej *newvpp = aliasvp; 336 1.3.2.2 thorpej return (0); 337 1.3.2.2 thorpej } 338 1.3.2.2 thorpej 339 1.3.2.2 thorpej struct vnode * 340 1.3.2.2 thorpej layer_checkvp(vp, fil, lno) 341 1.3.2.2 thorpej struct vnode *vp; 342 1.3.2.2 thorpej char *fil; 343 1.3.2.2 thorpej int lno; 344 1.3.2.2 thorpej { 345 1.3.2.2 thorpej struct layer_node *a = VTOLAYER(vp); 346 1.3.2.2 thorpej #ifdef notyet 347 1.3.2.2 thorpej /* 348 1.3.2.2 thorpej * Can't do this check because vop_reclaim runs 349 1.3.2.2 thorpej * with a funny vop vector. 350 1.3.2.2 thorpej * 351 1.3.2.2 thorpej * WRS - no it doesnt... 352 1.3.2.2 thorpej */ 353 1.3.2.2 thorpej if (vp->v_op != layer_vnodeop_p) { 354 1.3.2.2 thorpej printf ("layer_checkvp: on non-layer-node\n"); 355 1.3.2.2 thorpej #ifdef notyet 356 1.3.2.2 thorpej while (layer_checkvp_barrier) /*WAIT*/ ; 357 1.3.2.2 thorpej #endif 358 1.3.2.2 thorpej panic("layer_checkvp"); 359 1.3.2.2 thorpej }; 360 1.3.2.2 thorpej #endif 361 1.3.2.2 thorpej if (a->layer_lowervp == NULL) { 362 1.3.2.2 thorpej /* Should never happen */ 363 1.3.2.2 thorpej int i; u_long *p; 364 1.3.2.2 thorpej printf("vp = %p, ZERO ptr\n", vp); 365 1.3.2.2 thorpej for (p = (u_long *) a, i = 0; i < 8; i++) 366 1.3.2.2 thorpej printf(" %lx", p[i]); 367 1.3.2.2 thorpej printf("\n"); 368 1.3.2.2 thorpej /* wait for debugger */ 369 1.3.2.2 thorpej panic("layer_checkvp"); 370 1.3.2.2 thorpej } 371 1.3.2.2 thorpej if (a->layer_lowervp->v_usecount < 1) { 372 1.3.2.2 thorpej int i; u_long *p; 373 1.3.2.2 thorpej printf("vp = %p, unref'ed lowervp\n", vp); 374 1.3.2.2 thorpej for (p = (u_long *) a, i = 0; i < 8; i++) 375 1.3.2.2 thorpej printf(" %lx", p[i]); 376 1.3.2.2 thorpej printf("\n"); 377 1.3.2.2 thorpej /* wait for debugger */ 378 1.3.2.2 thorpej panic ("layer with unref'ed lowervp"); 379 1.3.2.2 thorpej }; 380 1.3.2.2 thorpej #ifdef notnow 381 1.3.2.2 thorpej printf("layer %p/%d -> %p/%d [%s, %d]\n", 382 1.3.2.2 thorpej LAYERTOV(a), LAYERTOV(a)->v_usecount, 383 1.3.2.2 thorpej a->layer_lowervp, a->layer_lowervp->v_usecount, 384 1.3.2.2 thorpej fil, lno); 385 1.3.2.2 thorpej #endif 386 1.3.2.2 thorpej return a->layer_lowervp; 387 1.3.2.2 thorpej } 388
Indexes created Fri Oct 03 02:09:57 GMT 2025