1 /* $NetBSD: vfs_init.c,v 1.18 2001/01/22 12:17:41 jdolecek 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. 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 const struct vnodeop_desc * const 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 const struct vnodeopv_desc dead_vnodeop_opv_desc; 112 extern const struct vnodeopv_desc fifo_vnodeop_opv_desc; 113 extern const struct vnodeopv_desc spec_vnodeop_opv_desc; 114 extern const struct vnodeopv_desc sync_vnodeop_opv_desc; 115 116 const struct vnodeopv_desc * const vfs_special_vnodeopv_descs[] = { 117 &dead_vnodeop_opv_desc, 118 &fifo_vnodeop_opv_desc, 119 &spec_vnodeop_opv_desc, 120 &sync_vnodeop_opv_desc, 121 NULL, 122 }; 123 124 /* 125 * This code doesn't work if the defn is **vnodop_defns with cc. 126 * The problem is because of the compiler sometimes putting in an 127 * extra level of indirection for arrays. It's an interesting 128 * "feature" of C. 129 */ 130 typedef int (*PFI) __P((void *)); 131 132 static void vfs_opv_init_explicit __P((const struct vnodeopv_desc *)); 133 static void vfs_opv_init_default __P((const struct vnodeopv_desc *)); 134 #ifdef DEBUG 135 static void vfs_op_check __P((void)); 136 #endif 137 138 /* 139 * A miscellaneous routine. 140 * A generic "default" routine that just returns an error. 141 */ 142 /*ARGSUSED*/ 143 int 144 vn_default_error(v) 145 void *v; 146 { 147 148 return (EOPNOTSUPP); 149 } 150 151 /* 152 * vfs_init.c 153 * 154 * Allocate and fill in operations vectors. 155 * 156 * An undocumented feature of this approach to defining operations is that 157 * there can be multiple entries in vfs_opv_descs for the same operations 158 * vector. This allows third parties to extend the set of operations 159 * supported by another layer in a binary compatibile way. For example, 160 * assume that NFS needed to be modified to support Ficus. NFS has an entry 161 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 162 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 163 * listing those new operations Ficus adds to NFS, all without modifying the 164 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 165 * that is a(whole)nother story.) This is a feature. 166 */ 167 168 /* 169 * Init the vector, if it needs it. 170 * Also handle backwards compatibility. 171 */ 172 static void 173 vfs_opv_init_explicit(vfs_opv_desc) 174 const struct vnodeopv_desc *vfs_opv_desc; 175 { 176 int (**opv_desc_vector) __P((void *)); 177 const struct vnodeopv_entry_desc *opve_descp; 178 179 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 180 181 for (opve_descp = vfs_opv_desc->opv_desc_ops; 182 opve_descp->opve_op; 183 opve_descp++) { 184 /* 185 * Sanity check: is this operation listed 186 * in the list of operations? We check this 187 * by seeing if its offest is zero. Since 188 * the default routine should always be listed 189 * first, it should be the only one with a zero 190 * offset. Any other operation with a zero 191 * offset is probably not listed in 192 * vfs_op_descs, and so is probably an error. 193 * 194 * A panic here means the layer programmer 195 * has committed the all-too common bug 196 * of adding a new operation to the layer's 197 * list of vnode operations but 198 * not adding the operation to the system-wide 199 * list of supported operations. 200 */ 201 if (opve_descp->opve_op->vdesc_offset == 0 && 202 opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) { 203 printf("operation %s not listed in %s.\n", 204 opve_descp->opve_op->vdesc_name, "vfs_op_descs"); 205 panic ("vfs_opv_init: bad operation"); 206 } 207 208 /* 209 * Fill in this entry. 210 */ 211 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 212 opve_descp->opve_impl; 213 } 214 } 215 216 static void 217 vfs_opv_init_default(vfs_opv_desc) 218 const struct vnodeopv_desc *vfs_opv_desc; 219 { 220 int j; 221 int (**opv_desc_vector) __P((void *)); 222 223 opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p); 224 225 /* 226 * Force every operations vector to have a default routine. 227 */ 228 if (opv_desc_vector[VOFFSET(vop_default)] == NULL) 229 panic("vfs_opv_init: operation vector without default routine."); 230 231 for (j = 0; j < VNODE_OPS_COUNT; j++) 232 if (opv_desc_vector[j] == NULL) 233 opv_desc_vector[j] = 234 opv_desc_vector[VOFFSET(vop_default)]; 235 } 236 237 void 238 vfs_opv_init(vopvdpp) 239 const struct vnodeopv_desc * const *vopvdpp; 240 { 241 int (**opv_desc_vector) __P((void *)); 242 int i; 243 244 /* 245 * Allocate the vectors. 246 */ 247 for (i = 0; vopvdpp[i] != NULL; i++) { 248 /* XXX - shouldn't be M_VNODE */ 249 opv_desc_vector = 250 malloc(VNODE_OPS_COUNT * sizeof(PFI), M_VNODE, M_WAITOK); 251 memset(opv_desc_vector, 0, VNODE_OPS_COUNT * sizeof(PFI)); 252 *(vopvdpp[i]->opv_desc_vector_p) = opv_desc_vector; 253 DODEBUG(printf("vector at %p allocated\n", 254 opv_desc_vector_p)); 255 } 256 257 /* 258 * ...and fill them in. 259 */ 260 for (i = 0; vopvdpp[i] != NULL; i++) 261 vfs_opv_init_explicit(vopvdpp[i]); 262 263 /* 264 * Finally, go back and replace unfilled routines 265 * with their default. 266 */ 267 for (i = 0; vopvdpp[i] != NULL; i++) 268 vfs_opv_init_default(vopvdpp[i]); 269 } 270 271 void 272 vfs_opv_free(vopvdpp) 273 const struct vnodeopv_desc * const *vopvdpp; 274 { 275 int i; 276 277 /* 278 * Free the vectors allocated in vfs_opv_init(). 279 */ 280 for (i = 0; vopvdpp[i] != NULL; i++) { 281 /* XXX - shouldn't be M_VNODE */ 282 free(*(vopvdpp[i]->opv_desc_vector_p), M_VNODE); 283 *(vopvdpp[i]->opv_desc_vector_p) = NULL; 284 } 285 } 286 287 #ifdef DEBUG 288 static void 289 vfs_op_check() 290 { 291 int i; 292 293 DODEBUG(printf("Vnode_interface_init.\n")); 294 295 /* 296 * Check offset of each op. 297 */ 298 for (i = 0; vfs_op_descs[i]; i++) { 299 if (vfs_op_descs[i]->vdesc_offset != i) 300 panic("vfs_op_check: vfs_op_desc[] offset mismatch"); 301 } 302 303 if (i != VNODE_OPS_COUNT) { 304 panic("vfs_op_check: vnode ops count mismatch (%d != %d)", 305 i, VNODE_OPS_COUNT); 306 } 307 308 DODEBUG(printf ("vfs_opv_numops=%d\n", VNODE_OPS_COUNT)); 309 } 310 #endif /* DEBUG */ 311 312 /* 313 * Routines having to do with the management of the vnode table. 314 */ 315 struct vattr va_null; 316 317 /* 318 * Initialize the vnode structures and initialize each file system type. 319 */ 320 void 321 vfsinit() 322 { 323 extern struct vfsops *vfs_list_initial[]; 324 int i; 325 326 /* 327 * Initialize the namei pathname buffer pool. 328 */ 329 pool_init(&pnbuf_pool, MAXPATHLEN, 0, 0, 0, "pnbufpl", 330 0, pool_page_alloc_nointr, pool_page_free_nointr, M_NAMEI); 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