vfs_init.c revision 12577
1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed 6 * to Berkeley by John Heidemann of the UCLA Ficus project. 7 * 8 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94 39 * $Id: vfs_init.c,v 1.15 1995/12/02 17:10:53 bde Exp $ 40 */ 41 42 43#include <sys/param.h> 44#include <sys/systm.h> 45#include <sys/kernel.h> 46#include <sys/mount.h> 47#include <sys/time.h> 48#include <sys/vnode.h> 49#include <sys/stat.h> 50#include <sys/namei.h> 51#include <sys/ucred.h> 52#include <sys/buf.h> 53#include <sys/errno.h> 54#include <sys/malloc.h> 55#include <sys/proc.h> 56#include <vm/vm.h> 57#include <sys/sysctl.h> 58 59extern void vfs_op_init __P((void)); 60 61static void vfsinit __P((void *)); 62SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 63 64void vfs_op_init __P((void)); 65 66/* 67 * Sigh, such primitive tools are these... 68 */ 69#if 0 70#define DODEBUG(A) A 71#else 72#define DODEBUG(A) 73#endif 74 75struct vfsconf void_vfsconf; 76 77extern struct linker_set vfs_opv_descs_; 78#define vfs_opv_descs ((struct vnodeopv_desc **)vfs_opv_descs_.ls_items) 79 80extern struct linker_set vfs_set; 81struct vfsops *vfssw[MOUNT_MAXTYPE + 1]; 82struct vfsconf *vfsconf[MOUNT_MAXTYPE + 1]; 83 84extern struct vnodeop_desc *vfs_op_descs[]; 85 /* and the operations they perform */ 86/* 87 * This code doesn't work if the defn is **vnodop_defns with cc. 88 * The problem is because of the compiler sometimes putting in an 89 * extra level of indirection for arrays. It's an interesting 90 * "feature" of C. 91 */ 92int vfs_opv_numops; 93 94/* 95 * A miscellaneous routine. 96 * A generic "default" routine that just returns an error. 97 */ 98int 99vn_default_error() 100{ 101 102 return (EOPNOTSUPP); 103} 104 105/* 106 * vfs_init.c 107 * 108 * Allocate and fill in operations vectors. 109 * 110 * An undocumented feature of this approach to defining operations is that 111 * there can be multiple entries in vfs_opv_descs for the same operations 112 * vector. This allows third parties to extend the set of operations 113 * supported by another layer in a binary compatibile way. For example, 114 * assume that NFS needed to be modified to support Ficus. NFS has an entry 115 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 116 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 117 * listing those new operations Ficus adds to NFS, all without modifying the 118 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 119 * that is a(whole)nother story.) This is a feature. 120 */ 121void 122vfs_opv_init(struct vnodeopv_desc **them) 123{ 124 int i, j, k; 125 vop_t ***opv_desc_vector_p; 126 vop_t **opv_desc_vector; 127 struct vnodeopv_entry_desc *opve_descp; 128 129 /* 130 * Allocate the dynamic vectors and fill them in. 131 */ 132 for (i=0; them[i]; i++) { 133 opv_desc_vector_p = them[i]->opv_desc_vector_p; 134 /* 135 * Allocate and init the vector, if it needs it. 136 * Also handle backwards compatibility. 137 */ 138 if (*opv_desc_vector_p == NULL) { 139 /* XXX - shouldn't be M_VNODE */ 140 MALLOC(*opv_desc_vector_p, vop_t **, 141 vfs_opv_numops * sizeof(vop_t *), M_VNODE, 142 M_WAITOK); 143 bzero(*opv_desc_vector_p, 144 vfs_opv_numops * sizeof(vop_t *)); 145 DODEBUG(printf("vector at %x allocated\n", 146 opv_desc_vector_p)); 147 } 148 opv_desc_vector = *opv_desc_vector_p; 149 for (j=0; them[i]->opv_desc_ops[j].opve_op; j++) { 150 opve_descp = &(them[i]->opv_desc_ops[j]); 151 152 /* 153 * Sanity check: is this operation listed 154 * in the list of operations? We check this 155 * by seeing if its offest is zero. Since 156 * the default routine should always be listed 157 * first, it should be the only one with a zero 158 * offset. Any other operation with a zero 159 * offset is probably not listed in 160 * vfs_op_descs, and so is probably an error. 161 * 162 * A panic here means the layer programmer 163 * has committed the all-too common bug 164 * of adding a new operation to the layer's 165 * list of vnode operations but 166 * not adding the operation to the system-wide 167 * list of supported operations. 168 */ 169 if (opve_descp->opve_op->vdesc_offset == 0 && 170 opve_descp->opve_op->vdesc_offset != 171 VOFFSET(vop_default)) { 172 printf("operation %s not listed in %s.\n", 173 opve_descp->opve_op->vdesc_name, 174 "vfs_op_descs"); 175 panic ("vfs_opv_init: bad operation"); 176 } 177 /* 178 * Fill in this entry. 179 */ 180 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 181 opve_descp->opve_impl; 182 } 183 } 184 /* 185 * Finally, go back and replace unfilled routines 186 * with their default. (Sigh, an O(n^3) algorithm. I 187 * could make it better, but that'd be work, and n is small.) 188 */ 189 for (i = 0; them[i]; i++) { 190 opv_desc_vector = *(them[i]->opv_desc_vector_p); 191 /* 192 * Force every operations vector to have a default routine. 193 */ 194 if (opv_desc_vector[VOFFSET(vop_default)]==NULL) { 195 panic("vfs_opv_init: operation vector without default routine."); 196 } 197 for (k = 0; k<vfs_opv_numops; k++) 198 if (opv_desc_vector[k] == NULL) 199 opv_desc_vector[k] = 200 opv_desc_vector[VOFFSET(vop_default)]; 201 } 202} 203 204/* 205 * Initialize known vnode operations vectors. 206 */ 207void 208vfs_op_init() 209{ 210 int i; 211 212 DODEBUG(printf("Vnode_interface_init.\n")); 213 /* 214 * Set all vnode vectors to a well known value. 215 */ 216 for (i = 0; vfs_opv_descs[i]; i++) 217 *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL; 218 /* 219 * Figure out how many ops there are by counting the table, 220 * and assign each its offset. 221 */ 222 for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) { 223 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops; 224 vfs_opv_numops++; 225 } 226 DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); 227} 228 229/* 230 * Routines having to do with the management of the vnode table. 231 */ 232extern struct vnodeops dead_vnodeops; 233extern struct vnodeops spec_vnodeops; 234struct vattr va_null; 235 236/* 237 * Initialize the vnode structures and initialize each file system type. 238 */ 239/* ARGSUSED*/ 240static void 241vfsinit(dummy) 242 void *dummy; 243{ 244 struct vfsops **vfsp; 245 struct vfsconf **vfc; 246 int i; 247 248 /* 249 * Initialize the VFS switch table 250 */ 251 for(i = 0; i < MOUNT_MAXTYPE + 1; i++) { 252 vfsconf[i] = &void_vfsconf; 253 } 254 255 vfc = (struct vfsconf **)vfs_set.ls_items; 256 while(*vfc) { 257 vfssw[(**vfc).vfc_index] = (**vfc).vfc_vfsops; 258 vfsconf[(**vfc).vfc_index] = *vfc; 259 vfc++; 260 } 261 262 /* 263 * Initialize the vnode table 264 */ 265 vntblinit(); 266 /* 267 * Initialize the vnode name cache 268 */ 269 nchinit(); 270 /* 271 * Build vnode operation vectors. 272 */ 273 vfs_op_init(); 274 vfs_opv_init(vfs_opv_descs); /* finish the job */ 275 /* 276 * Initialize each file system type. 277 */ 278 vattr_null(&va_null); 279 for (vfsp = &vfssw[0]; vfsp <= &vfssw[MOUNT_MAXTYPE]; vfsp++) { 280 if (*vfsp == NULL) 281 continue; 282 (*(*vfsp)->vfs_init)(); 283 } 284} 285 286/* 287 * kernel related system variables. 288 */ 289 290static int 291sysctl_fs_vfsconf SYSCTL_HANDLER_ARGS 292{ 293 int i, error; 294 295 if (req->newptr) 296 return EINVAL; 297 for(i = 0; i < MOUNT_MAXTYPE + 1; i++) { 298 error = SYSCTL_OUT(req, vfsconf[i], sizeof *vfsconf[i]); 299 if(error) 300 return error; 301 } 302 return (error); 303 304} 305 306SYSCTL_PROC(_fs, FS_VFSCONF, vfsconf, CTLTYPE_OPAQUE|CTLFLAG_RD, 307 0, 0, sysctl_fs_vfsconf, ""); 308 309/* 310 * This goop is here to support a loadable NFS module... grumble... 311 */ 312void (*lease_check) __P((struct vnode *, struct proc *, struct ucred *, int)) 313 = 0; 314void (*lease_updatetime) __P((int)) 315 = 0; 316 317