vfs_init.c revision 23254
1178476Sjb/* 2178476Sjb * Copyright (c) 1989, 1993 3178476Sjb * The Regents of the University of California. All rights reserved. 4178476Sjb * 5178476Sjb * This code is derived from software contributed 6178476Sjb * to Berkeley by John Heidemann of the UCLA Ficus project. 7178476Sjb * 8178476Sjb * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 9178476Sjb * 10178476Sjb * Redistribution and use in source and binary forms, with or without 11178476Sjb * modification, are permitted provided that the following conditions 12178476Sjb * are met: 13178476Sjb * 1. Redistributions of source code must retain the above copyright 14178476Sjb * notice, this list of conditions and the following disclaimer. 15178476Sjb * 2. Redistributions in binary form must reproduce the above copyright 16178476Sjb * notice, this list of conditions and the following disclaimer in the 17178476Sjb * documentation and/or other materials provided with the distribution. 18178476Sjb * 3. All advertising materials mentioning features or use of this software 19178476Sjb * must display the following acknowledgement: 20178476Sjb * This product includes software developed by the University of 21178476Sjb * California, Berkeley and its contributors. 22178476Sjb * 4. Neither the name of the University nor the names of its contributors 23178476Sjb * may be used to endorse or promote products derived from this software 24178476Sjb * without specific prior written permission. 25178476Sjb * 26178476Sjb * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27178476Sjb * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28178476Sjb * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29178476Sjb * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30178476Sjb * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31178476Sjb * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32178476Sjb * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33178476Sjb * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34178476Sjb * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35178476Sjb * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36178476Sjb * SUCH DAMAGE. 37178476Sjb * 38178476Sjb * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94 39178476Sjb * $Id: vfs_init.c,v 1.24 1997/02/22 09:39:32 peter Exp $ 40178476Sjb */ 41178476Sjb 42178476Sjb 43178476Sjb#include <sys/param.h> 44178476Sjb#include <sys/systm.h> 45178476Sjb#include <sys/kernel.h> 46178476Sjb#include <sys/mount.h> 47178476Sjb#include <sys/time.h> 48178476Sjb#include <sys/vnode.h> 49178476Sjb#include <sys/stat.h> 50178476Sjb#include <sys/namei.h> 51178476Sjb#include <sys/ucred.h> 52178476Sjb#include <sys/buf.h> 53178476Sjb#include <sys/errno.h> 54178476Sjb#include <sys/malloc.h> 55178476Sjb#include <sys/proc.h> 56178476Sjb 57178476Sjbstatic void vfs_op_init __P((void)); 58178476Sjb 59static void vfsinit __P((void *)); 60SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 61 62/* 63 * Sigh, such primitive tools are these... 64 */ 65#if 0 66#define DODEBUG(A) A 67#else 68#define DODEBUG(A) 69#endif 70 71struct vfsconf void_vfsconf; 72 73extern struct linker_set vfs_opv_descs_; 74#define vfs_opv_descs ((struct vnodeopv_desc **)vfs_opv_descs_.ls_items) 75 76extern struct linker_set vfs_set; 77 78extern struct vnodeop_desc *vfs_op_descs[]; 79 /* and the operations they perform */ 80/* 81 * This code doesn't work if the defn is **vnodop_defns with cc. 82 * The problem is because of the compiler sometimes putting in an 83 * extra level of indirection for arrays. It's an interesting 84 * "feature" of C. 85 */ 86static int vfs_opv_numops; 87 88/* 89 * A miscellaneous routine. 90 * A generic "default" routine that just returns an error. 91 */ 92int 93vn_default_error() 94{ 95 96 return (EOPNOTSUPP); 97} 98 99/* 100 * vfs_init.c 101 * 102 * Allocate and fill in operations vectors. 103 * 104 * An undocumented feature of this approach to defining operations is that 105 * there can be multiple entries in vfs_opv_descs for the same operations 106 * vector. This allows third parties to extend the set of operations 107 * supported by another layer in a binary compatibile way. For example, 108 * assume that NFS needed to be modified to support Ficus. NFS has an entry 109 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 110 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 111 * listing those new operations Ficus adds to NFS, all without modifying the 112 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 113 * that is a(whole)nother story.) This is a feature. 114 */ 115void 116vfs_opv_init(struct vnodeopv_desc **them) 117{ 118 int i, j, k; 119 vop_t ***opv_desc_vector_p; 120 vop_t **opv_desc_vector; 121 struct vnodeopv_entry_desc *opve_descp; 122 123 /* 124 * Allocate the dynamic vectors and fill them in. 125 */ 126 for (i=0; them[i]; i++) { 127 opv_desc_vector_p = them[i]->opv_desc_vector_p; 128 /* 129 * Allocate and init the vector, if it needs it. 130 * Also handle backwards compatibility. 131 */ 132 if (*opv_desc_vector_p == NULL) { 133 /* XXX - shouldn't be M_VNODE */ 134 MALLOC(*opv_desc_vector_p, vop_t **, 135 vfs_opv_numops * sizeof(vop_t *), M_VNODE, 136 M_WAITOK); 137 bzero(*opv_desc_vector_p, 138 vfs_opv_numops * sizeof(vop_t *)); 139 DODEBUG(printf("vector at %x allocated\n", 140 opv_desc_vector_p)); 141 } 142 opv_desc_vector = *opv_desc_vector_p; 143 for (j=0; them[i]->opv_desc_ops[j].opve_op; j++) { 144 opve_descp = &(them[i]->opv_desc_ops[j]); 145 146 /* 147 * Sanity check: is this operation listed 148 * in the list of operations? We check this 149 * by seeing if its offest is zero. Since 150 * the default routine should always be listed 151 * first, it should be the only one with a zero 152 * offset. Any other operation with a zero 153 * offset is probably not listed in 154 * vfs_op_descs, and so is probably an error. 155 * 156 * A panic here means the layer programmer 157 * has committed the all-too common bug 158 * of adding a new operation to the layer's 159 * list of vnode operations but 160 * not adding the operation to the system-wide 161 * list of supported operations. 162 */ 163 if (opve_descp->opve_op->vdesc_offset == 0 && 164 opve_descp->opve_op->vdesc_offset != 165 VOFFSET(vop_default)) { 166 printf("operation %s not listed in %s.\n", 167 opve_descp->opve_op->vdesc_name, 168 "vfs_op_descs"); 169 panic ("vfs_opv_init: bad operation"); 170 } 171 /* 172 * Fill in this entry. 173 */ 174 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 175 opve_descp->opve_impl; 176 } 177 } 178 /* 179 * Finally, go back and replace unfilled routines 180 * with their default. (Sigh, an O(n^3) algorithm. I 181 * could make it better, but that'd be work, and n is small.) 182 */ 183 for (i = 0; them[i]; i++) { 184 opv_desc_vector = *(them[i]->opv_desc_vector_p); 185 /* 186 * Force every operations vector to have a default routine. 187 */ 188 if (opv_desc_vector[VOFFSET(vop_default)]==NULL) { 189 panic("vfs_opv_init: operation vector without default routine."); 190 } 191 for (k = 0; k<vfs_opv_numops; k++) 192 if (opv_desc_vector[k] == NULL) 193 opv_desc_vector[k] = 194 opv_desc_vector[VOFFSET(vop_default)]; 195 } 196} 197 198/* 199 * Initialize known vnode operations vectors. 200 */ 201static void 202vfs_op_init() 203{ 204 int i; 205 206 DODEBUG(printf("Vnode_interface_init.\n")); 207 /* 208 * Set all vnode vectors to a well known value. 209 */ 210 for (i = 0; vfs_opv_descs[i]; i++) 211 *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL; 212 /* 213 * Figure out how many ops there are by counting the table, 214 * and assign each its offset. 215 */ 216 for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) { 217 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops; 218 vfs_opv_numops++; 219 } 220 DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); 221} 222 223/* 224 * Routines having to do with the management of the vnode table. 225 */ 226extern struct vnodeops dead_vnodeops; 227extern struct vnodeops spec_vnodeops; 228struct vattr va_null; 229 230/* 231 * Initialize the vnode structures and initialize each file system type. 232 */ 233/* ARGSUSED*/ 234static void 235vfsinit(dummy) 236 void *dummy; 237{ 238 struct vfsconf **vfc; 239 int maxtypenum; 240 241 /* 242 * Initialize the vnode table 243 */ 244 vntblinit(); 245 /* 246 * Initialize the vnode name cache 247 */ 248 nchinit(); 249 /* 250 * Build vnode operation vectors. 251 */ 252 vfs_op_init(); 253 vfs_opv_init(vfs_opv_descs); /* finish the job */ 254 /* 255 * Initialize each file system type. 256 */ 257 vattr_null(&va_null); 258 maxtypenum = 0; 259 vfc = (struct vfsconf **)vfs_set.ls_items; 260 vfsconf = *vfc; /* simulate Lite2 vfsconf array */ 261 while (*vfc) { 262 struct vfsconf *vfsp = *vfc; 263 264 vfc++; 265 vfsp->vfc_next = *vfc; 266 if (maxtypenum <= vfsp->vfc_typenum) 267 maxtypenum = vfsp->vfc_typenum + 1; 268 (*vfsp->vfc_vfsops->vfs_init)(vfsp); 269 } 270 /* next vfc_typenum to be used */ 271 maxvfsconf = maxtypenum; 272} 273 274/* 275 * kernel related system variables. 276 */ 277 278/* 279 * This goop is here to support a loadable NFS module... grumble... 280 */ 281int (*lease_check_hook) __P((struct vop_lease_args *)) 282 = 0; 283void (*lease_updatetime) __P((int)) 284 = 0; 285 286int 287lease_check(ap) 288 struct vop_lease_args /* { 289 struct vnode *a_vp; 290 struct proc *a_p; 291 struct ucred *a_cred; 292 int a_flag; 293 } */ *ap; 294{ 295 if (lease_check_hook) 296 return (*lease_check_hook)(ap); 297 else 298 return 0; 299} 300