1 /* $NetBSD: vfs_init.c,v 1.14 1998/08/04 04:03:18 perry Exp $ */ 2 3 /*- 4 * Copyright (c) 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * NASA Ames Research Center. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 /* 41 * Copyright (c) 1989, 1993 42 * The Regents of the University of California. All rights reserved. 43 * 44 * This code is derived from software contributed 45 * to Berkeley by John Heidemann of the UCLA Ficus project. 46 * 47 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 48 * 49 * Redistribution and use in source and binary forms, with or without 50 * modification, are permitted provided that the following conditions 51 * are met: 52 * 1. Redistributions of source code must retain the above copyright 53 * notice, this list of conditions and the following disclaimer. 54 * 2. Redistributions in binary form must reproduce the above copyright 55 * notice, this list of conditions and the following disclaimer in the 56 * documentation and/or other materials provided with the distribution. 57 * 3. All advertising materials mentioning features or use of this software 58 * must display the following acknowledgement: 59 * This product includes software developed by the University of 60 * California, Berkeley and its contributors. 61 * 4. Neither the name of the University nor the names of its contributors 62 * may be used to endorse or promote products derived from this software 63 * without specific prior written permission. 64 * 65 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 66 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 67 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 68 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 69 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 70 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 71 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 72 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 73 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 74 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 75 * SUCH DAMAGE. 76 * 77 * @(#)vfs_init.c 8.5 (Berkeley) 5/11/95 78 */ 79 80 #include <sys/param.h> 81 #include <sys/mount.h> 82 #include <sys/time.h> 83 #include <sys/vnode.h> 84 #include <sys/stat.h> 85 #include <sys/namei.h> 86 #include <sys/ucred.h> 87 #include <sys/buf.h> 88 #include <sys/errno.h> 89 #include <sys/malloc.h> 90 #include <sys/systm.h> 91 92 /* 93 * Sigh, such primitive tools are these... 94 */ 95 #if 0 96 #define DODEBUG(A) A 97 #else 98 #define DODEBUG(A) 99 #endif 100 101 /* 102 * The global list of vnode operations. 103 */ 104 extern struct vnodeop_desc *vfs_op_descs[]; 105 106 /* 107 * These vnodeopv_descs are listed here because they are not 108 * associated with any particular file system, and thus cannot 109 * be initialized by vfs_attach(). 110 */ 111 extern struct vnodeopv_desc dead_vnodeop_opv_desc; 112 extern struct vnodeopv_desc fifo_vnodeop_opv_desc; 113 extern struct vnodeopv_desc spec_vnodeop_opv_desc; 114 115 struct vnodeopv_desc *vfs_special_vnodeopv_descs[] = { 116 &dead_vnodeop_opv_desc, 117 &fifo_vnodeop_opv_desc, 118 &spec_vnodeop_opv_desc, 119 NULL, 120 }; 121 122 /* 123 * This code doesn't work if the defn is **vnodop_defns with cc. 124 * The problem is because of the compiler sometimes putting in an 125 * extra level of indirection for arrays. It's an interesting 126 * "feature" of C. 127 */ 128 int vfs_opv_numops; 129 130 typedef int (*PFI) __P((void *)); 131 132 void vfs_opv_init_explicit __P((struct vnodeopv_desc *)); 133 void vfs_opv_init_default __P((struct vnodeopv_desc *)); 134 void vfs_op_init __P((void)); 135 136 /* 137 * A miscellaneous routine. 138 * A generic "default" routine that just returns an error. 139 */ 140 /*ARGSUSED*/ 141 int 142 vn_default_error(v) 143 void *v; 144 { 145 146 return (EOPNOTSUPP); 147 } 148 149 /* 150 * vfs_init.c 151 * 152 * Allocate and fill in operations vectors. 153 * 154 * An undocumented feature of this approach to defining operations is that 155 * there can be multiple entries in vfs_opv_descs for the same operations 156 * vector. This allows third parties to extend the set of operations 157 * supported by another layer in a binary compatibile way. For example, 158 * assume that NFS needed to be modified to support Ficus. NFS has an entry 159 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 160 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 161 * listing those new operations Ficus adds to NFS, all without modifying the 162 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 163 * that is a(whole)nother story.) This is a feature. 164 */ 165 166 /* 167 * Init the vector, if it needs it. 168 * Also handle backwards compatibility. 169 */ 170 void 171 vfs_opv_init_explicit(vfs_opv_desc) 172 struct vnodeopv_desc *vfs_opv_desc; 173 { 174 int (**opv_desc_vector) __P((void *)); 175 struct vnodeopv_entry_desc *opve_descp; 176 177 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 178 179 for (opve_descp = vfs_opv_desc->opv_desc_ops; 180 opve_descp->opve_op; 181 opve_descp++) { 182 /* 183 * Sanity check: is this operation listed 184 * in the list of operations? We check this 185 * by seeing if its offest is zero. Since 186 * the default routine should always be listed 187 * first, it should be the only one with a zero 188 * offset. Any other operation with a zero 189 * offset is probably not listed in 190 * vfs_op_descs, and so is probably an error. 191 * 192 * A panic here means the layer programmer 193 * has committed the all-too common bug 194 * of adding a new operation to the layer's 195 * list of vnode operations but 196 * not adding the operation to the system-wide 197 * list of supported operations. 198 */ 199 if (opve_descp->opve_op->vdesc_offset == 0 && 200 opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) { 201 printf("operation %s not listed in %s.\n", 202 opve_descp->opve_op->vdesc_name, "vfs_op_descs"); 203 panic ("vfs_opv_init: bad operation"); 204 } 205 206 /* 207 * Fill in this entry. 208 */ 209 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 210 opve_descp->opve_impl; 211 } 212 } 213 214 void 215 vfs_opv_init_default(vfs_opv_desc) 216 struct vnodeopv_desc *vfs_opv_desc; 217 { 218 int j; 219 int (**opv_desc_vector) __P((void *)); 220 221 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 222 223 /* 224 * Force every operations vector to have a default routine. 225 */ 226 if (opv_desc_vector[VOFFSET(vop_default)] == NULL) 227 panic("vfs_opv_init: operation vector without default routine."); 228 229 for (j = 0; j < vfs_opv_numops; j++) 230 if (opv_desc_vector[j] == NULL) 231 opv_desc_vector[j] = 232 opv_desc_vector[VOFFSET(vop_default)]; 233 } 234 235 void 236 vfs_opv_init(vopvdpp) 237 struct vnodeopv_desc **vopvdpp; 238 { 239 int (**opv_desc_vector) __P((void *)); 240 int i; 241 242 /* 243 * Allocate the vectors. 244 */ 245 for (i = 0; vopvdpp[i] != NULL; i++) { 246 /* XXX - shouldn't be M_VNODE */ 247 opv_desc_vector = 248 malloc(vfs_opv_numops * sizeof(PFI), M_VNODE, M_WAITOK); 249 memset(opv_desc_vector, 0, vfs_opv_numops * sizeof(PFI)); 250 *(vopvdpp[i]->opv_desc_vector_p) = opv_desc_vector; 251 DODEBUG(printf("vector at %p allocated\n", 252 opv_desc_vector_p)); 253 } 254 255 /* 256 * ...and fill them in. 257 */ 258 for (i = 0; vopvdpp[i] != NULL; i++) 259 vfs_opv_init_explicit(vopvdpp[i]); 260 261 /* 262 * Finally, go back and replace unfilled routines 263 * with their default. 264 */ 265 for (i = 0; vopvdpp[i] != NULL; i++) 266 vfs_opv_init_default(vopvdpp[i]); 267 } 268 269 void 270 vfs_opv_free(vopvdpp) 271 struct vnodeopv_desc **vopvdpp; 272 { 273 int i; 274 275 /* 276 * Free the vectors allocated in vfs_opv_init(). 277 */ 278 for (i = 0; vopvdpp[i] != NULL; i++) { 279 /* XXX - shouldn't be M_VNODE */ 280 free(*(vopvdpp[i]->opv_desc_vector_p), M_VNODE); 281 *(vopvdpp[i]->opv_desc_vector_p) = NULL; 282 } 283 } 284 285 void 286 vfs_op_init() 287 { 288 int i; 289 290 DODEBUG(printf("Vnode_interface_init.\n")); 291 /* 292 * Figure out how many ops there are by counting the table, 293 * and assign each its offset. 294 */ 295 for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) { 296 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops; 297 vfs_opv_numops++; 298 } 299 DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); 300 } 301 302 /* 303 * Routines having to do with the management of the vnode table. 304 */ 305 struct vattr va_null; 306 307 /* 308 * Initialize the vnode structures and initialize each file system type. 309 */ 310 void 311 vfsinit() 312 { 313 extern struct vfsops *vfs_list_initial[]; 314 int i; 315 316 /* 317 * Initialize the vnode table 318 */ 319 vntblinit(); 320 321 /* 322 * Initialize the vnode name cache 323 */ 324 nchinit(); 325 326 /* 327 * Initialize the list of vnode operations. 328 */ 329 vfs_op_init(); 330 331 /* 332 * Initialize the special vnode operations. 333 */ 334 vfs_opv_init(vfs_special_vnodeopv_descs); 335 336 /* 337 * Establish each file system which was statically 338 * included in the kernel. 339 */ 340 vattr_null(&va_null); 341 for (i = 0; vfs_list_initial[i] != NULL; i++) { 342 if (vfs_attach(vfs_list_initial[i])) { 343 printf("multiple `%s' file systems", 344 vfs_list_initial[i]->vfs_name); 345 panic("vfsinit"); 346 } 347 } 348 } 349