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 1.40 1998/11/15 15:18:30 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/sysctl.h> 48 #include <sys/vnode.h> 49 #include <sys/malloc.h> 50 #include <vm/vm_zone.h> 51 52 53 MALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes"); 54 55 /* 56 * XXX this bloat just exands the sysctl__vfs linker set a little so that 57 * we can attach sysctls for VFS modules without expanding the linker set. 58 * Currently (1998/09/06), only one VFS uses sysctls, so 2 extra linker 59 * set slots are more than sufficient. 60 */ 61 extern struct linker_set sysctl__vfs; 62 static int mod_xx; 63 SYSCTL_INT(_vfs, OID_AUTO, mod0, CTLFLAG_RD, &mod_xx, 0, ""); 64 SYSCTL_INT(_vfs, OID_AUTO, mod1, CTLFLAG_RD, &mod_xx, 0, ""); 65 66 /* 67 * Zone for namei 68 */ 69 struct vm_zone *namei_zone; 70 71 /* 72 * vfs_init.c 73 * 74 * Allocate and fill in operations vectors. 75 * 76 * An undocumented feature of this approach to defining operations is that 77 * there can be multiple entries in vfs_opv_descs for the same operations 78 * vector. This allows third parties to extend the set of operations 79 * supported by another layer in a binary compatibile way. For example, 80 * assume that NFS needed to be modified to support Ficus. NFS has an entry 81 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 82 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 83 * listing those new operations Ficus adds to NFS, all without modifying the 84 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 85 * that is a(whole)nother story.) This is a feature. 86 */ 87 88 /* Table of known vnodeop vectors (list of VFS vnode vectors) */ 89 static struct vnodeopv_desc **vnodeopv_descs; 90 static int vnodeopv_num; 91 92 /* Table of known descs (list of vnode op handlers "vop_access_desc") */ 93 static struct vnodeop_desc **vfs_op_descs; 94 static int *vfs_op_desc_refs; /* reference counts */ 95 static int num_op_descs; 96 static int vfs_opv_numops; 97 98 static void 99 vfs_opv_recalc(void) 100 { 101 int i, j; 102 vop_t ***opv_desc_vector_p; 103 vop_t **opv_desc_vector; 104 struct vnodeopv_entry_desc *opve_descp; 105 struct vnodeopv_desc *opv; 106 107 if (vfs_op_descs == NULL) 108 panic("vfs_opv_recalc called with null vfs_op_descs"); 109 110 /* 111 * Run through and make sure all known descs have an offset 112 * 113 * vop_default_desc is hardwired at offset 1, and offset 0 114 * is a panic sanity check. 115 */ 116 vfs_opv_numops = 0; 117 for (i = 0; i < num_op_descs; i++) 118 if (vfs_opv_numops < (vfs_op_descs[i]->vdesc_offset + 1)) 119 vfs_opv_numops = vfs_op_descs[i]->vdesc_offset + 1; 120 for (i = 0; i < num_op_descs; i++) 121 if (vfs_op_descs[i]->vdesc_offset == 0) 122 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops++; 123 /* 124 * Allocate and fill in the vectors 125 */ 126 for (i = 0; i < vnodeopv_num; i++) { 127 opv = vnodeopv_descs[i]; 128 opv_desc_vector_p = opv->opv_desc_vector_p; 129 if (*opv_desc_vector_p) 130 FREE(*opv_desc_vector_p, M_VNODE); 131 MALLOC(*opv_desc_vector_p, vop_t **, 132 vfs_opv_numops * sizeof(vop_t *), M_VNODE, M_WAITOK); 133 if (*opv_desc_vector_p == NULL) 134 panic("no memory for vop_t ** vector"); 135 bzero(*opv_desc_vector_p, vfs_opv_numops * sizeof(vop_t *)); 136 137 /* Fill in, with slot 0 being panic */ 138 opv_desc_vector = *opv_desc_vector_p; 139 opv_desc_vector[0] = (vop_t *)vop_panic; 140 for (j = 0; opv->opv_desc_ops[j].opve_op; j++) { 141 opve_descp = &(opv->opv_desc_ops[j]); 142 opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 143 opve_descp->opve_impl; 144 } 145 146 /* Replace unfilled routines with their default (slot 1). */ 147 opv_desc_vector = *(opv->opv_desc_vector_p); 148 if (opv_desc_vector[1] == NULL) 149 panic("vfs_opv_recalc: vector without a default."); 150 for (j = 0; j < vfs_opv_numops; j++) 151 if (opv_desc_vector[j] == NULL) 152 opv_desc_vector[j] = opv_desc_vector[1]; 153 } 154 } 155 156 void 157 vfs_add_vnodeops(void *data) 158 { 159 struct vnodeopv_desc *opv; 160 struct vnodeopv_desc **newopv; 161 struct vnodeop_desc **newop; 162 int *newref; 163 vop_t **opv_desc_vector; 164 struct vnodeop_desc *desc; 165 int i, j; 166 167 opv = (struct vnodeopv_desc *)data; 168 MALLOC(newopv, struct vnodeopv_desc **, 169 (vnodeopv_num + 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 170 if (newopv == NULL) 171 panic("vfs_add_vnodeops: no memory"); 172 if (vnodeopv_descs) { 173 bcopy(vnodeopv_descs, newopv, vnodeopv_num * sizeof(*newopv)); 174 FREE(vnodeopv_descs, M_VNODE); 175 } 176 newopv[vnodeopv_num] = opv; 177 vnodeopv_descs = newopv; 178 vnodeopv_num++; 179 180 /* See if we have turned up a new vnode op desc */ 181 opv_desc_vector = *(opv->opv_desc_vector_p); 182 for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 183 for (j = 0; j < num_op_descs; j++) { 184 if (desc == vfs_op_descs[j]) { 185 /* found it, increase reference count */ 186 vfs_op_desc_refs[j]++; 187 break; 188 } 189 } 190 if (j == num_op_descs) { 191 /* not found, new entry */ 192 MALLOC(newop, struct vnodeop_desc **, 193 (num_op_descs + 1) * sizeof(*newop), 194 M_VNODE, M_WAITOK); 195 if (newop == NULL) 196 panic("vfs_add_vnodeops: no memory for desc"); 197 /* new reference count (for unload) */ 198 MALLOC(newref, int *, 199 (num_op_descs + 1) * sizeof(*newref), 200 M_VNODE, M_WAITOK); 201 if (newref == NULL) 202 panic("vfs_add_vnodeops: no memory for refs"); 203 if (vfs_op_descs) { 204 bcopy(vfs_op_descs, newop, 205 num_op_descs * sizeof(*newop)); 206 FREE(vfs_op_descs, M_VNODE); 207 } 208 if (vfs_op_desc_refs) { 209 bcopy(vfs_op_desc_refs, newref, 210 num_op_descs * sizeof(*newref)); 211 FREE(vfs_op_desc_refs, M_VNODE); 212 } 213 newop[num_op_descs] = desc; 214 newref[num_op_descs] = 1; 215 vfs_op_descs = newop; 216 vfs_op_desc_refs = newref; 217 num_op_descs++; 218 } 219 } 220 vfs_opv_recalc(); 221 } 222 223 void 224 vfs_rm_vnodeops(void *data) 225 { 226 struct vnodeopv_desc *opv; 227 struct vnodeopv_desc **newopv; 228 struct vnodeop_desc **newop; 229 int *newref; 230 vop_t **opv_desc_vector; 231 struct vnodeop_desc *desc; 232 int i, j, k; 233 234 opv = (struct vnodeopv_desc *)data; 235 /* Lower ref counts on descs in the table and release if zero */ 236 opv_desc_vector = *(opv->opv_desc_vector_p); 237 for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 238 for (j = 0; j < num_op_descs; j++) { 239 if (desc == vfs_op_descs[j]) { 240 /* found it, decrease reference count */ 241 vfs_op_desc_refs[j]--; 242 break; 243 } 244 } 245 for (j = 0; j < num_op_descs; j++) { 246 if (vfs_op_desc_refs[j] > 0) 247 continue; 248 if (vfs_op_desc_refs[j] < 0) 249 panic("vfs_remove_vnodeops: negative refcnt"); 250 MALLOC(newop, struct vnodeop_desc **, 251 (num_op_descs - 1) * sizeof(*newop), 252 M_VNODE, M_WAITOK); 253 if (newop == NULL) 254 panic("vfs_remove_vnodeops: no memory for desc"); 255 /* new reference count (for unload) */ 256 MALLOC(newref, int *, 257 (num_op_descs - 1) * sizeof(*newref), 258 M_VNODE, M_WAITOK); 259 if (newref == NULL) 260 panic("vfs_remove_vnodeops: no memory for refs"); 261 for (k = j; k < (num_op_descs - 1); k++) { 262 vfs_op_descs[k] = vfs_op_descs[k + 1]; 263 vfs_op_desc_refs[k] = vfs_op_desc_refs[k + 1]; 264 } 265 bcopy(vfs_op_descs, newop, 266 (num_op_descs - 1) * sizeof(*newop)); 267 bcopy(vfs_op_desc_refs, newref, 268 (num_op_descs - 1) * sizeof(*newref)); 269 FREE(vfs_op_descs, M_VNODE); 270 FREE(vfs_op_desc_refs, M_VNODE); 271 vfs_op_descs = newop; 272 vfs_op_desc_refs = newref; 273 num_op_descs--; 274 } 275 } 276 277 for (i = 0; i < vnodeopv_num; i++) { 278 if (vnodeopv_descs[i] == opv) { 279 for (j = i; j < (vnodeopv_num - 1); j++) 280 vnodeopv_descs[j] = vnodeopv_descs[j + 1]; 281 break; 282 } 283 } 284 if (i == vnodeopv_num) 285 panic("vfs_remove_vnodeops: opv not found"); 286 MALLOC(newopv, struct vnodeopv_desc **, 287 (vnodeopv_num - 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 288 if (newopv == NULL) 289 panic("vfs_remove_vnodeops: no memory"); 290 bcopy(vnodeopv_descs, newopv, (vnodeopv_num - 1) * sizeof(*newopv)); 291 FREE(vnodeopv_descs, M_VNODE); 292 vnodeopv_descs = newopv; 293 vnodeopv_num--; 294 295 vfs_opv_recalc(); 296 } 297 298 /* 299 * Routines having to do with the management of the vnode table. 300 */ 301 struct vattr va_null; 302 303 /* 304 * Initialize the vnode structures and initialize each file system type. 305 */ 306 /* ARGSUSED*/ 307 static void 308 vfsinit(void *dummy) 309 { 310 311 namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2); 312 313 /* 314 * Initialize the vnode table 315 */ 316 vntblinit(); 317 /* 318 * Initialize the vnode name cache 319 */ 320 nchinit(); 321 /* 322 * Initialize each file system type. 323 * Vfs type numbers must be distinct from VFS_GENERIC (and VFS_VFSCONF). 324 */ 325 vattr_null(&va_null); 326 maxvfsconf = VFS_GENERIC + 1; 327 } 328 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 329 330 int 331 vfs_register(struct vfsconf *vfc) 332 { 333 struct linker_set *l; 334 struct sysctl_oid **oidpp; 335 struct vfsconf *vfsp; 336 int i, exists; 337 338 vfsp = NULL; 339 l = &sysctl__vfs; 340 if (vfsconf) 341 for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next) 342 if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 343 return EEXIST; 344 345 vfc->vfc_typenum = maxvfsconf++; 346 if (vfc->vfc_vfsops->vfs_oid != NULL) { 347 /* 348 * Attach the oid to the "vfs" node of the sysctl tree if 349 * it isn't already there (it will be there for statically 350 * configured vfs's). 351 */ 352 exists = 0; 353 for (i = l->ls_length, 354 oidpp = (struct sysctl_oid **)l->ls_items; 355 i-- != 0; oidpp++) 356 if (*oidpp == vfc->vfc_vfsops->vfs_oid) { 357 exists = 1; 358 break; 359 } 360 if (exists == 0) 361 for (i = l->ls_length, 362 oidpp = (struct sysctl_oid **)l->ls_items; 363 i-- != 0; oidpp++) { 364 if (*oidpp == NULL || 365 *oidpp == &sysctl___vfs_mod0 || 366 *oidpp == &sysctl___vfs_mod1) { 367 *oidpp = vfc->vfc_vfsops->vfs_oid; 368 break; 369 } 370 } 371 372 vfc->vfc_vfsops->vfs_oid->oid_number = vfc->vfc_typenum; 373 sysctl_order_all(); 374 } 375 if (vfsp) 376 vfsp->vfc_next = vfc; 377 else 378 vfsconf = vfc; 379 vfc->vfc_next = NULL; 380 381 /* 382 * Call init function for this VFS... 383 */ 384 (*(vfc->vfc_vfsops->vfs_init))(vfc); 385 386 return 0; 387 } 388 389 390 int 391 vfs_unregister(struct vfsconf *vfc) 392 { 393 struct linker_set *l; 394 struct sysctl_oid **oidpp; 395 struct vfsconf *vfsp, *prev_vfsp; 396 int error, i, maxtypenum; 397 398 i = vfc->vfc_typenum; 399 400 prev_vfsp = NULL; 401 for (vfsp = vfsconf; vfsp; 402 prev_vfsp = vfsp, vfsp = vfsp->vfc_next) { 403 if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 404 break; 405 } 406 if (vfsp == NULL) 407 return EINVAL; 408 if (vfsp->vfc_refcount) 409 return EBUSY; 410 if (vfc->vfc_vfsops->vfs_uninit != NULL) { 411 error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp); 412 if (error) 413 return (error); 414 } 415 if (prev_vfsp) 416 prev_vfsp->vfc_next = vfsp->vfc_next; 417 else 418 vfsconf = vfsp->vfc_next; 419 if (vfsp->vfc_vfsops->vfs_oid != NULL) { 420 l = &sysctl__vfs; 421 for (i = l->ls_length, 422 oidpp = (struct sysctl_oid **)l->ls_items; 423 i--; oidpp++) { 424 if (*oidpp == vfsp->vfc_vfsops->vfs_oid) { 425 *oidpp = NULL; 426 sysctl_order_all(); 427 break; 428 } 429 } 430 } 431 maxtypenum = VFS_GENERIC; 432 for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next) 433 if (maxtypenum < vfsp->vfc_typenum) 434 maxtypenum = vfsp->vfc_typenum; 435 maxvfsconf = maxtypenum + 1; 436 return 0; 437 } 438 439 int 440 vfs_modevent(module_t mod, int type, void *data) 441 { 442 struct vfsconf *vfc; 443 int error = 0; 444 445 vfc = (struct vfsconf *)data; 446 447 switch (type) { 448 case MOD_LOAD: 449 if (vfc) 450 error = vfs_register(vfc); 451 break; 452 453 case MOD_UNLOAD: 454 if (vfc) 455 error = vfs_unregister(vfc); 456 break; 457 default: /* including MOD_SHUTDOWN */ 458 break; 459 } 460 return (error); 461 } 462