1 /* $NetBSD: vfs_init.c,v 1.25 2004/03/23 13:22:05 junyoung Exp $ */ 2 3 /*- 4 * Copyright (c) 1998, 2000 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. Neither the name of the University nor the names of its contributors 58 * may be used to endorse or promote products derived from this software 59 * without specific prior written permission. 60 * 61 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 62 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 63 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 64 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 65 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 66 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 67 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 68 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 69 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 70 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 71 * SUCH DAMAGE. 72 * 73 * @(#)vfs_init.c 8.5 (Berkeley) 5/11/95 74 */ 75 76 #include <sys/cdefs.h> 77 __KERNEL_RCSID(0, "$NetBSD: vfs_init.c,v 1.25 2004/03/23 13:22:05 junyoung Exp $"); 78 79 #include <sys/param.h> 80 #include <sys/mount.h> 81 #include <sys/time.h> 82 #include <sys/vnode.h> 83 #include <sys/stat.h> 84 #include <sys/namei.h> 85 #include <sys/ucred.h> 86 #include <sys/buf.h> 87 #include <sys/errno.h> 88 #include <sys/malloc.h> 89 #include <sys/systm.h> 90 91 /* 92 * Sigh, such primitive tools are these... 93 */ 94 #if 0 95 #define DODEBUG(A) A 96 #else 97 #define DODEBUG(A) 98 #endif 99 100 /* 101 * The global list of vnode operations. 102 */ 103 extern const struct vnodeop_desc * const vfs_op_descs[]; 104 105 /* 106 * These vnodeopv_descs are listed here because they are not 107 * associated with any particular file system, and thus cannot 108 * be initialized by vfs_attach(). 109 */ 110 extern const struct vnodeopv_desc dead_vnodeop_opv_desc; 111 extern const struct vnodeopv_desc fifo_vnodeop_opv_desc; 112 extern const struct vnodeopv_desc spec_vnodeop_opv_desc; 113 extern const struct vnodeopv_desc sync_vnodeop_opv_desc; 114 115 const struct vnodeopv_desc * const vfs_special_vnodeopv_descs[] = { 116 &dead_vnodeop_opv_desc, 117 &fifo_vnodeop_opv_desc, 118 &spec_vnodeop_opv_desc, 119 &sync_vnodeop_opv_desc, 120 NULL, 121 }; 122 123 /* 124 * This code doesn't work if the defn is **vnodop_defns with cc. 125 * The problem is because of the compiler sometimes putting in an 126 * extra level of indirection for arrays. It's an interesting 127 * "feature" of C. 128 */ 129 typedef int (*PFI)(void *); 130 131 static void vfs_opv_init_explicit(const struct vnodeopv_desc *); 132 static void vfs_opv_init_default(const struct vnodeopv_desc *); 133 #ifdef DEBUG 134 static void vfs_op_check(void); 135 #endif 136 137 /* 138 * A miscellaneous routine. 139 * A generic "default" routine that just returns an error. 140 */ 141 /*ARGSUSED*/ 142 int 143 vn_default_error(v) 144 void *v; 145 { 146 147 return (EOPNOTSUPP); 148 } 149 150 /* 151 * vfs_init.c 152 * 153 * Allocate and fill in operations vectors. 154 * 155 * An undocumented feature of this approach to defining operations is that 156 * there can be multiple entries in vfs_opv_descs for the same operations 157 * vector. This allows third parties to extend the set of operations 158 * supported by another layer in a binary compatibile way. For example, 159 * assume that NFS needed to be modified to support Ficus. NFS has an entry 160 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 161 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 162 * listing those new operations Ficus adds to NFS, all without modifying the 163 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 164 * that is a(whole)nother story.) This is a feature. 165 */ 166 167 /* 168 * Init the vector, if it needs it. 169 * Also handle backwards compatibility. 170 */ 171 static void 172 vfs_opv_init_explicit(vfs_opv_desc) 173 const struct vnodeopv_desc *vfs_opv_desc; 174 { 175 int (**opv_desc_vector)(void *); 176 const struct vnodeopv_entry_desc *opve_descp; 177 178 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 179 180 for (opve_descp = vfs_opv_desc->opv_desc_ops; 181 opve_descp->opve_op; 182 opve_descp++) { 183 /* 184 * Sanity check: is this operation listed 185 * in the list of operations? We check this 186 * by seeing if its offset is zero. Since 187 * the default routine should always be listed 188 * first, it should be the only one with a zero 189 * offset. Any other operation with a zero 190 * offset is probably not listed in 191 * vfs_op_descs, and so is probably an error. 192 * 193 * A panic here means the layer programmer 194 * has committed the all-too common bug 195 * of adding a new operation to the layer's 196 * list of vnode operations but 197 * not adding the operation to the system-wide 198 * list of supported operations. 199 */ 200 if (opve_descp->opve_op->vdesc_offset == 0 && 201 opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) { 202 printf("operation %s not listed in %s.\n", 203 opve_descp->opve_op->vdesc_name, "vfs_op_descs"); 204 panic ("vfs_opv_init: bad operation"); 205 } 206 207 /* 208 * Fill in this entry. 209 */ 210 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 211 opve_descp->opve_impl; 212 } 213 } 214 215 static void 216 vfs_opv_init_default(vfs_opv_desc) 217 const struct vnodeopv_desc *vfs_opv_desc; 218 { 219 int j; 220 int (**opv_desc_vector)(void *); 221 222 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 223 224 /* 225 * Force every operations vector to have a default routine. 226 */ 227 if (opv_desc_vector[VOFFSET(vop_default)] == NULL) 228 panic("vfs_opv_init: operation vector without default routine."); 229 230 for (j = 0; j < VNODE_OPS_COUNT; j++) 231 if (opv_desc_vector[j] == NULL) 232 opv_desc_vector[j] = 233 opv_desc_vector[VOFFSET(vop_default)]; 234 } 235 236 void 237 vfs_opv_init(vopvdpp) 238 const struct vnodeopv_desc * const *vopvdpp; 239 { 240 int (**opv_desc_vector)(void *); 241 int i; 242 243 /* 244 * Allocate the vectors. 245 */ 246 for (i = 0; vopvdpp[i] != NULL; i++) { 247 /* XXX - shouldn't be M_VNODE */ 248 opv_desc_vector = 249 malloc(VNODE_OPS_COUNT * sizeof(PFI), M_VNODE, M_WAITOK); 250 memset(opv_desc_vector, 0, VNODE_OPS_COUNT * sizeof(PFI)); 251 *(vopvdpp[i]->opv_desc_vector_p) = opv_desc_vector; 252 DODEBUG(printf("vector at %p allocated\n", 253 opv_desc_vector_p)); 254 } 255 256 /* 257 * ...and fill them in. 258 */ 259 for (i = 0; vopvdpp[i] != NULL; i++) 260 vfs_opv_init_explicit(vopvdpp[i]); 261 262 /* 263 * Finally, go back and replace unfilled routines 264 * with their default. 265 */ 266 for (i = 0; vopvdpp[i] != NULL; i++) 267 vfs_opv_init_default(vopvdpp[i]); 268 } 269 270 void 271 vfs_opv_free(vopvdpp) 272 const struct vnodeopv_desc * const *vopvdpp; 273 { 274 int i; 275 276 /* 277 * Free the vectors allocated in vfs_opv_init(). 278 */ 279 for (i = 0; vopvdpp[i] != NULL; i++) { 280 /* XXX - shouldn't be M_VNODE */ 281 free(*(vopvdpp[i]->opv_desc_vector_p), M_VNODE); 282 *(vopvdpp[i]->opv_desc_vector_p) = NULL; 283 } 284 } 285 286 #ifdef DEBUG 287 static void 288 vfs_op_check() 289 { 290 int i; 291 292 DODEBUG(printf("Vnode_interface_init.\n")); 293 294 /* 295 * Check offset of each op. 296 */ 297 for (i = 0; vfs_op_descs[i]; i++) { 298 if (vfs_op_descs[i]->vdesc_offset != i) 299 panic("vfs_op_check: vfs_op_desc[] offset mismatch"); 300 } 301 302 if (i != VNODE_OPS_COUNT) { 303 panic("vfs_op_check: vnode ops count mismatch (%d != %d)", 304 i, VNODE_OPS_COUNT); 305 } 306 307 DODEBUG(printf ("vfs_opv_numops=%d\n", VNODE_OPS_COUNT)); 308 } 309 #endif /* DEBUG */ 310 311 /* 312 * Routines having to do with the management of the vnode table. 313 */ 314 struct vattr va_null; 315 316 /* 317 * Initialize the vnode structures and initialize each file system type. 318 */ 319 void 320 vfsinit() 321 { 322 extern struct vfsops * const vfs_list_initial[]; 323 int i; 324 325 /* 326 * Initialize the namei pathname buffer pool and cache. 327 */ 328 pool_init(&pnbuf_pool, MAXPATHLEN, 0, 0, 0, "pnbufpl", 329 &pool_allocator_nointr); 330 pool_cache_init(&pnbuf_cache, &pnbuf_pool, NULL, NULL, NULL); 331 332 /* 333 * Initialize the vnode table 334 */ 335 vntblinit(); 336 337 /* 338 * Initialize the vnode name cache 339 */ 340 nchinit(); 341 342 #ifdef DEBUG 343 /* 344 * Check the list of vnode operations. 345 */ 346 vfs_op_check(); 347 #endif 348 349 /* 350 * Initialize the special vnode operations. 351 */ 352 vfs_opv_init(vfs_special_vnodeopv_descs); 353 354 /* 355 * Establish each file system which was statically 356 * included in the kernel. 357 */ 358 vattr_null(&va_null); 359 for (i = 0; vfs_list_initial[i] != NULL; i++) { 360 if (vfs_attach(vfs_list_initial[i])) { 361 printf("multiple `%s' file systems", 362 vfs_list_initial[i]->vfs_name); 363 panic("vfsinit"); 364 } 365 } 366 } 367