vfs_init.c revision 12913
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 1.18 1995/12/04 16:48:34 phk 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 59static void vfs_op_init __P((void)); 60 61static void vfsinit __P((void *)); 62SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 63 64/* 65 * Sigh, such primitive tools are these... 66 */ 67#if 0 68#define DODEBUG(A) A 69#else 70#define DODEBUG(A) 71#endif 72 73struct vfsconf void_vfsconf; 74 75extern struct linker_set vfs_opv_descs_; 76#define vfs_opv_descs ((struct vnodeopv_desc **)vfs_opv_descs_.ls_items) 77 78extern struct linker_set vfs_set; 79struct vfsops *vfssw[MOUNT_MAXTYPE + 1]; 80struct vfsconf *vfsconf[MOUNT_MAXTYPE + 1]; 81 82extern struct vnodeop_desc *vfs_op_descs[]; 83 /* and the operations they perform */ 84/* 85 * This code doesn't work if the defn is **vnodop_defns with cc. 86 * The problem is because of the compiler sometimes putting in an 87 * extra level of indirection for arrays. It's an interesting 88 * "feature" of C. 89 */ 90static int vfs_opv_numops; 91 92/* 93 * A miscellaneous routine. 94 * A generic "default" routine that just returns an error. 95 */ 96int 97vn_default_error() 98{ 99 100 return (EOPNOTSUPP); 101} 102 103/* 104 * vfs_init.c 105 * 106 * Allocate and fill in operations vectors. 107 * 108 * An undocumented feature of this approach to defining operations is that 109 * there can be multiple entries in vfs_opv_descs for the same operations 110 * vector. This allows third parties to extend the set of operations 111 * supported by another layer in a binary compatibile way. For example, 112 * assume that NFS needed to be modified to support Ficus. NFS has an entry 113 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 114 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 115 * listing those new operations Ficus adds to NFS, all without modifying the 116 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 117 * that is a(whole)nother story.) This is a feature. 118 */ 119void 120vfs_opv_init(struct vnodeopv_desc **them) 121{ 122 int i, j, k; 123 vop_t ***opv_desc_vector_p; 124 vop_t **opv_desc_vector; 125 struct vnodeopv_entry_desc *opve_descp; 126 127 /* 128 * Allocate the dynamic vectors and fill them in. 129 */ 130 for (i=0; them[i]; i++) { 131 opv_desc_vector_p = them[i]->opv_desc_vector_p; 132 /* 133 * Allocate and init the vector, if it needs it. 134 * Also handle backwards compatibility. 135 */ 136 if (*opv_desc_vector_p == NULL) { 137 /* XXX - shouldn't be M_VNODE */ 138 MALLOC(*opv_desc_vector_p, vop_t **, 139 vfs_opv_numops * sizeof(vop_t *), M_VNODE, 140 M_WAITOK); 141 bzero(*opv_desc_vector_p, 142 vfs_opv_numops * sizeof(vop_t *)); 143 DODEBUG(printf("vector at %x allocated\n", 144 opv_desc_vector_p)); 145 } 146 opv_desc_vector = *opv_desc_vector_p; 147 for (j=0; them[i]->opv_desc_ops[j].opve_op; j++) { 148 opve_descp = &(them[i]->opv_desc_ops[j]); 149 150 /* 151 * Sanity check: is this operation listed 152 * in the list of operations? We check this 153 * by seeing if its offest is zero. Since 154 * the default routine should always be listed 155 * first, it should be the only one with a zero 156 * offset. Any other operation with a zero 157 * offset is probably not listed in 158 * vfs_op_descs, and so is probably an error. 159 * 160 * A panic here means the layer programmer 161 * has committed the all-too common bug 162 * of adding a new operation to the layer's 163 * list of vnode operations but 164 * not adding the operation to the system-wide 165 * list of supported operations. 166 */ 167 if (opve_descp->opve_op->vdesc_offset == 0 && 168 opve_descp->opve_op->vdesc_offset != 169 VOFFSET(vop_default)) { 170 printf("operation %s not listed in %s.\n", 171 opve_descp->opve_op->vdesc_name, 172 "vfs_op_descs"); 173 panic ("vfs_opv_init: bad operation"); 174 } 175 /* 176 * Fill in this entry. 177 */ 178 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 179 opve_descp->opve_impl; 180 } 181 } 182 /* 183 * Finally, go back and replace unfilled routines 184 * with their default. (Sigh, an O(n^3) algorithm. I 185 * could make it better, but that'd be work, and n is small.) 186 */ 187 for (i = 0; them[i]; i++) { 188 opv_desc_vector = *(them[i]->opv_desc_vector_p); 189 /* 190 * Force every operations vector to have a default routine. 191 */ 192 if (opv_desc_vector[VOFFSET(vop_default)]==NULL) { 193 panic("vfs_opv_init: operation vector without default routine."); 194 } 195 for (k = 0; k<vfs_opv_numops; k++) 196 if (opv_desc_vector[k] == NULL) 197 opv_desc_vector[k] = 198 opv_desc_vector[VOFFSET(vop_default)]; 199 } 200} 201 202/* 203 * Initialize known vnode operations vectors. 204 */ 205static void 206vfs_op_init() 207{ 208 int i; 209 210 DODEBUG(printf("Vnode_interface_init.\n")); 211 /* 212 * Set all vnode vectors to a well known value. 213 */ 214 for (i = 0; vfs_opv_descs[i]; i++) 215 *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL; 216 /* 217 * Figure out how many ops there are by counting the table, 218 * and assign each its offset. 219 */ 220 for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) { 221 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops; 222 vfs_opv_numops++; 223 } 224 DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); 225} 226 227/* 228 * Routines having to do with the management of the vnode table. 229 */ 230extern struct vnodeops dead_vnodeops; 231extern struct vnodeops spec_vnodeops; 232struct vattr va_null; 233 234/* 235 * Initialize the vnode structures and initialize each file system type. 236 */ 237/* ARGSUSED*/ 238static void 239vfsinit(dummy) 240 void *dummy; 241{ 242 struct vfsops **vfsp; 243 struct vfsconf **vfc; 244 int i; 245 246 /* 247 * Initialize the VFS switch table 248 */ 249 for(i = 0; i < MOUNT_MAXTYPE + 1; i++) { 250 vfsconf[i] = &void_vfsconf; 251 } 252 253 vfc = (struct vfsconf **)vfs_set.ls_items; 254 while(*vfc) { 255 vfssw[(**vfc).vfc_index] = (**vfc).vfc_vfsops; 256 vfsconf[(**vfc).vfc_index] = *vfc; 257 vfc++; 258 } 259 260 /* 261 * Initialize the vnode table 262 */ 263 vntblinit(); 264 /* 265 * Initialize the vnode name cache 266 */ 267 nchinit(); 268 /* 269 * Build vnode operation vectors. 270 */ 271 vfs_op_init(); 272 vfs_opv_init(vfs_opv_descs); /* finish the job */ 273 /* 274 * Initialize each file system type. 275 */ 276 vattr_null(&va_null); 277 for (vfsp = &vfssw[0]; vfsp <= &vfssw[MOUNT_MAXTYPE]; vfsp++) { 278 if (*vfsp == NULL) 279 continue; 280 (*(*vfsp)->vfs_init)(); 281 } 282} 283 284/* 285 * kernel related system variables. 286 */ 287 288static int 289sysctl_fs_vfsconf SYSCTL_HANDLER_ARGS 290{ 291 int i, error; 292 293 if (req->newptr) 294 return EINVAL; 295 for(i = 0; i < MOUNT_MAXTYPE + 1; i++) { 296 error = SYSCTL_OUT(req, vfsconf[i], sizeof *vfsconf[i]); 297 if(error) 298 return error; 299 } 300 return (error); 301 302} 303 304SYSCTL_PROC(_fs, FS_VFSCONF, vfsconf, CTLTYPE_OPAQUE|CTLFLAG_RD, 305 0, 0, sysctl_fs_vfsconf, "S,vfsconf", ""); 306 307/* 308 * This goop is here to support a loadable NFS module... grumble... 309 */ 310void (*lease_check) __P((struct vnode *, struct proc *, struct ucred *, int)) 311 = 0; 312void (*lease_updatetime) __P((int)) 313 = 0; 314 315