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 1.31 1997/10/26 20:26:33 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/vnode.h> 48 #include <sys/malloc.h> 49 #include <vm/vm_zone.h> 50 51 static void vfs_op_init __P((void)); 52 53 static void vfsinit __P((void *)); 54 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 55 56 MALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes"); 57 58 /* 59 * Sigh, such primitive tools are these... 60 */ 61 #if 0 62 #define DODEBUG(A) A 63 #else 64 #define DODEBUG(A) 65 #endif 66 67 static struct vfsconf void_vfsconf; 68 69 extern struct linker_set vfs_opv_descs_; 70 #define vfs_opv_descs ((struct vnodeopv_desc **)vfs_opv_descs_.ls_items) 71 72 extern struct linker_set vfs_set; 73 74 extern struct vnodeop_desc *vfs_op_descs[]; 75 /* and the operations they perform */ 76 77 /* 78 * Zone for namei 79 */ 80 struct vm_zone *namei_zone; 81 82 /* 83 * vfs_init.c 84 * 85 * Allocate and fill in operations vectors. 86 * 87 * An undocumented feature of this approach to defining operations is that 88 * there can be multiple entries in vfs_opv_descs for the same operations 89 * vector. This allows third parties to extend the set of operations 90 * supported by another layer in a binary compatibile way. For example, 91 * assume that NFS needed to be modified to support Ficus. NFS has an entry 92 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 93 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 94 * listing those new operations Ficus adds to NFS, all without modifying the 95 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 96 * that is a(whole)nother story.) This is a feature. 97 * 98 * Without an explicit reserve area, however, you must replace vnode_if.c 99 * and vnode_if.h when you do this, or you will be derefrencing of the 100 * end of vfs_op_descs[]. This is a flaw in the use of a structure 101 * pointer array rather than an agregate to define vfs_op_descs. So 102 * it's not a very dynamic "feature". 103 */ 104 void 105 vfs_opv_init(struct vnodeopv_desc **them) 106 { 107 int i, j, k; 108 vop_t ***opv_desc_vector_p; 109 vop_t **opv_desc_vector; 110 struct vnodeopv_entry_desc *opve_descp; 111 112 /* 113 * Allocate the dynamic vectors and fill them in. 114 */ 115 for (i=0; them[i]; i++) { 116 opv_desc_vector_p = them[i]->opv_desc_vector_p; 117 /* 118 * Allocate and init the vector, if it needs it. 119 * Also handle backwards compatibility. 120 */ 121 if (*opv_desc_vector_p == NULL) { 122 /* XXX - shouldn't be M_VNODE */ 123 MALLOC(*opv_desc_vector_p, vop_t **, 124 vfs_opv_numops * sizeof(vop_t *), M_VNODE, 125 M_WAITOK); 126 bzero(*opv_desc_vector_p, 127 vfs_opv_numops * sizeof(vop_t *)); 128 DODEBUG(printf("vector at %x allocated\n", 129 opv_desc_vector_p)); 130 } 131 opv_desc_vector = *opv_desc_vector_p; 132 for (j=0; them[i]->opv_desc_ops[j].opve_op; j++) { 133 opve_descp = &(them[i]->opv_desc_ops[j]); 134 135 /* 136 * Sanity check: is this operation listed 137 * in the list of operations? We check this 138 * by seeing if its offest is zero. Since 139 * the default routine should always be listed 140 * first, it should be the only one with a zero 141 * offset. Any other operation with a zero 142 * offset is probably not listed in 143 * vfs_op_descs, and so is probably an error. 144 * 145 * A panic here means the layer programmer 146 * has committed the all-too common bug 147 * of adding a new operation to the layer's 148 * list of vnode operations but 149 * not adding the operation to the system-wide 150 * list of supported operations. 151 */ 152 if (opve_descp->opve_op->vdesc_offset == 0 && 153 opve_descp->opve_op->vdesc_offset != 154 VOFFSET(vop_default)) { 155 printf("operation %s not listed in %s.\n", 156 opve_descp->opve_op->vdesc_name, 157 "vfs_op_descs"); 158 panic ("vfs_opv_init: bad operation"); 159 } 160 /* 161 * Fill in this entry. 162 */ 163 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 164 opve_descp->opve_impl; 165 } 166 } 167 /* 168 * Finally, go back and replace unfilled routines 169 * with their default. (Sigh, an O(n^3) algorithm. I 170 * could make it better, but that'd be work, and n is small.) 171 */ 172 for (i = 0; them[i]; i++) { 173 opv_desc_vector = *(them[i]->opv_desc_vector_p); 174 /* 175 * Force every operations vector to have a default routine. 176 */ 177 if (opv_desc_vector[VOFFSET(vop_default)]==NULL) { 178 panic("vfs_opv_init: operation vector without default routine."); 179 } 180 for (k = 0; k<vfs_opv_numops; k++) 181 if (opv_desc_vector[k] == NULL) 182 opv_desc_vector[k] = 183 opv_desc_vector[VOFFSET(vop_default)]; 184 } 185 } 186 187 /* 188 * Initialize known vnode operations vectors. 189 */ 190 static void 191 vfs_op_init() 192 { 193 int i; 194 195 DODEBUG(printf("Vnode_interface_init.\n")); 196 DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); 197 /* 198 * Set all vnode vectors to a well known value. 199 */ 200 for (i = 0; vfs_opv_descs[i]; i++) 201 *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL; 202 /* 203 * assign each op to its offset 204 * 205 * XXX This should not be needed, but is because the per 206 * XXX FS ops tables are not sorted according to the 207 * XXX vnodeop_desc's offset in vfs_op_descs. This 208 * XXX is the same reason we have to take the hit for 209 * XXX the static inline function calls instead of using 210 * XXX simple macro references. 211 */ 212 for (i = 0; i < vfs_opv_numops; i++) 213 vfs_op_descs[i]->vdesc_offset = i; 214 } 215 216 /* 217 * Routines having to do with the management of the vnode table. 218 */ 219 extern struct vnodeops dead_vnodeops; 220 extern struct vnodeops spec_vnodeops; 221 struct vattr va_null; 222 223 /* 224 * Initialize the vnode structures and initialize each file system type. 225 */ 226 /* ARGSUSED*/ 227 static void 228 vfsinit(dummy) 229 void *dummy; 230 { 231 struct vfsconf **vfc; 232 int maxtypenum; 233 234 namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2); 235 236 /* 237 * Initialize the vnode table 238 */ 239 vntblinit(); 240 /* 241 * Initialize the vnode name cache 242 */ 243 nchinit(); 244 /* 245 * Build vnode operation vectors. 246 */ 247 vfs_op_init(); 248 vfs_opv_init(vfs_opv_descs); /* finish the job */ 249 /* 250 * Initialize each file system type. 251 */ 252 vattr_null(&va_null); 253 maxtypenum = 0; 254 vfc = (struct vfsconf **)vfs_set.ls_items; 255 vfsconf = *vfc; /* simulate Lite2 vfsconf array */ 256 while (*vfc) { 257 struct vfsconf *vfsp = *vfc; 258 259 vfc++; 260 vfsp->vfc_next = *vfc; 261 if (maxtypenum <= vfsp->vfc_typenum) 262 maxtypenum = vfsp->vfc_typenum + 1; 263 (*vfsp->vfc_vfsops->vfs_init)(vfsp); 264 } 265 /* next vfc_typenum to be used */ 266 maxvfsconf = maxtypenum; 267 } 268 269