2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed
6 * to Berkeley by John Heidemann of the UCLA Ficus project.
8 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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
38 * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94
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>
53 MALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes");
56 * The highest defined VFS number.
58 int maxvfsconf = VFS_GENERIC + 1;
61 * Single-linked list of configured VFSes.
62 * New entries are added/deleted by vfs_register()/vfs_unregister()
64 struct vfsconf *vfsconf;
69 * Allocate and fill in operations vectors.
71 * An undocumented feature of this approach to defining operations is that
72 * there can be multiple entries in vfs_opv_descs for the same operations
73 * vector. This allows third parties to extend the set of operations
74 * supported by another layer in a binary compatibile way. For example,
75 * assume that NFS needed to be modified to support Ficus. NFS has an entry
76 * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by
77 * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions)
78 * listing those new operations Ficus adds to NFS, all without modifying the
79 * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but
80 * that is a(whole)nother story.) This is a feature.
83 /* Table of known vnodeop vectors (list of VFS vnode vectors) */
84 static const struct vnodeopv_desc **vnodeopv_descs;
85 static int vnodeopv_num;
87 /* Table of known descs (list of vnode op handlers "vop_access_desc") */
88 static struct vnodeop_desc **vfs_op_descs;
89 /* Reference counts for vfs_op_descs */
90 static int *vfs_op_desc_refs;
91 /* Number of descriptions */
92 static int num_op_descs;
93 /* Number of entries in each description */
94 static int vfs_opv_numops;
97 * Recalculate the operations vector/description (those parts of it that can
98 * be recalculated, that is.)
99 * XXX It may be preferable to replace this function with an invariant check
100 * and a set of functions that should keep the table invariant.
106 vop_t ***opv_desc_vector_p;
107 vop_t **opv_desc_vector;
108 struct vnodeopv_entry_desc *opve_descp;
109 const struct vnodeopv_desc *opv;
111 if (vfs_op_descs == NULL)
112 panic("vfs_opv_recalc called with null vfs_op_descs");
115 * Run through and make sure all known descs have an offset
117 * vop_default_desc is hardwired at offset 1, and offset 0
118 * is a panic sanity check.
121 for (i = 0; i < num_op_descs; i++)
122 if (vfs_opv_numops < (vfs_op_descs[i]->vdesc_offset + 1))
123 vfs_opv_numops = vfs_op_descs[i]->vdesc_offset + 1;
124 for (i = 0; i < num_op_descs; i++)
125 if (vfs_op_descs[i]->vdesc_offset == 0)
126 vfs_op_descs[i]->vdesc_offset = vfs_opv_numops++;
128 * Allocate and fill in the vectors
130 for (i = 0; i < vnodeopv_num; i++) {
131 opv = vnodeopv_descs[i];
132 opv_desc_vector_p = opv->opv_desc_vector_p;
133 if (*opv_desc_vector_p)
134 FREE(*opv_desc_vector_p, M_VNODE);
135 MALLOC(*opv_desc_vector_p, vop_t **,
136 vfs_opv_numops * sizeof(vop_t *), M_VNODE,
138 if (*opv_desc_vector_p == NULL)
139 panic("no memory for vop_t ** vector");
141 /* Fill in, with slot 0 being to return EOPNOTSUPP */
142 opv_desc_vector = *opv_desc_vector_p;
143 opv_desc_vector[0] = (vop_t *)vop_eopnotsupp;
144 for (j = 0; opv->opv_desc_ops[j].opve_op; j++) {
145 opve_descp = &(opv->opv_desc_ops[j]);
146 opv_desc_vector[opve_descp->opve_op->vdesc_offset] =
147 opve_descp->opve_impl;
150 /* Replace unfilled routines with their default (slot 1). */
151 opv_desc_vector = *(opv->opv_desc_vector_p);
152 if (opv_desc_vector[1] == NULL)
153 panic("vfs_opv_recalc: vector without a default.");
154 for (j = 0; j < vfs_opv_numops; j++)
155 if (opv_desc_vector[j] == NULL)
156 opv_desc_vector[j] = opv_desc_vector[1];
160 /* Add a set of vnode operations (a description) to the table above. */
162 vfs_add_vnodeops(const void *data)
164 const struct vnodeopv_desc *opv;
165 const struct vnodeopv_desc **newopv;
166 struct vnodeop_desc **newop;
168 vop_t **opv_desc_vector;
169 struct vnodeop_desc *desc;
172 opv = (const struct vnodeopv_desc *)data;
173 MALLOC(newopv, const struct vnodeopv_desc **,
174 (vnodeopv_num + 1) * sizeof(*newopv), M_VNODE, M_WAITOK);
176 panic("vfs_add_vnodeops: no memory");
177 if (vnodeopv_descs) {
178 bcopy(vnodeopv_descs, newopv, vnodeopv_num * sizeof(*newopv));
179 FREE(vnodeopv_descs, M_VNODE);
181 newopv[vnodeopv_num] = opv;
182 vnodeopv_descs = newopv;
185 /* See if we have turned up a new vnode op desc */
186 opv_desc_vector = *(opv->opv_desc_vector_p);
187 for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) {
188 for (j = 0; j < num_op_descs; j++) {
189 if (desc == vfs_op_descs[j]) {
190 /* found it, increase reference count */
191 vfs_op_desc_refs[j]++;
195 if (j == num_op_descs) {
196 /* not found, new entry */
197 MALLOC(newop, struct vnodeop_desc **,
198 (num_op_descs + 1) * sizeof(*newop),
201 panic("vfs_add_vnodeops: no memory for desc");
202 /* new reference count (for unload) */
203 MALLOC(newref, int *,
204 (num_op_descs + 1) * sizeof(*newref),
207 panic("vfs_add_vnodeops: no memory for refs");
209 bcopy(vfs_op_descs, newop,
210 num_op_descs * sizeof(*newop));
211 FREE(vfs_op_descs, M_VNODE);
213 if (vfs_op_desc_refs) {
214 bcopy(vfs_op_desc_refs, newref,
215 num_op_descs * sizeof(*newref));
216 FREE(vfs_op_desc_refs, M_VNODE);
218 newop[num_op_descs] = desc;
219 newref[num_op_descs] = 1;
220 vfs_op_descs = newop;
221 vfs_op_desc_refs = newref;
228 /* Remove a vnode type from the vnode description table above. */
230 vfs_rm_vnodeops(const void *data)
232 const struct vnodeopv_desc *opv;
233 const struct vnodeopv_desc **newopv;
234 struct vnodeop_desc **newop;
236 vop_t **opv_desc_vector;
237 struct vnodeop_desc *desc;
240 opv = (const struct vnodeopv_desc *)data;
241 /* Lower ref counts on descs in the table and release if zero */
242 opv_desc_vector = *(opv->opv_desc_vector_p);
243 for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) {
244 for (j = 0; j < num_op_descs; j++) {
245 if (desc == vfs_op_descs[j]) {
246 /* found it, decrease reference count */
247 vfs_op_desc_refs[j]--;
251 for (j = 0; j < num_op_descs; j++) {
252 if (vfs_op_desc_refs[j] > 0)
254 if (vfs_op_desc_refs[j] < 0)
255 panic("vfs_remove_vnodeops: negative refcnt");
256 MALLOC(newop, struct vnodeop_desc **,
257 (num_op_descs - 1) * sizeof(*newop),
260 panic("vfs_remove_vnodeops: no memory for desc");
261 /* new reference count (for unload) */
262 MALLOC(newref, int *,
263 (num_op_descs - 1) * sizeof(*newref),
266 panic("vfs_remove_vnodeops: no memory for refs");
267 for (k = j; k < (num_op_descs - 1); k++) {
268 vfs_op_descs[k] = vfs_op_descs[k + 1];
269 vfs_op_desc_refs[k] = vfs_op_desc_refs[k + 1];
271 bcopy(vfs_op_descs, newop,
272 (num_op_descs - 1) * sizeof(*newop));
273 bcopy(vfs_op_desc_refs, newref,
274 (num_op_descs - 1) * sizeof(*newref));
275 FREE(vfs_op_descs, M_VNODE);
276 FREE(vfs_op_desc_refs, M_VNODE);
277 vfs_op_descs = newop;
278 vfs_op_desc_refs = newref;
283 for (i = 0; i < vnodeopv_num; i++) {
284 if (vnodeopv_descs[i] == opv) {
285 for (j = i; j < (vnodeopv_num - 1); j++)
286 vnodeopv_descs[j] = vnodeopv_descs[j + 1];
290 if (i == vnodeopv_num)
291 panic("vfs_remove_vnodeops: opv not found");
292 MALLOC(newopv, const struct vnodeopv_desc **,
293 (vnodeopv_num - 1) * sizeof(*newopv), M_VNODE, M_WAITOK);
295 panic("vfs_remove_vnodeops: no memory");
296 bcopy(vnodeopv_descs, newopv, (vnodeopv_num - 1) * sizeof(*newopv));
297 FREE(vnodeopv_descs, M_VNODE);
298 vnodeopv_descs = newopv;
305 * Routines having to do with the management of the vnode table.
307 struct vattr va_null;
310 * Initialize the vnode structures and initialize each file system type.
317 vattr_null(&va_null);
319 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL)
321 /* Register a new file system type in the global table */
323 vfs_register(struct vfsconf *vfc)
325 struct sysctl_oid *oidp;
326 struct vfsconf *vfsp;
330 for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next)
331 if (strcmp(vfc->vfc_name, vfsp->vfc_name) == 0)
334 vfc->vfc_typenum = maxvfsconf++;
336 vfsp->vfc_next = vfc;
339 vfc->vfc_next = NULL;
342 * If this filesystem has a sysctl node under vfs
343 * (i.e. vfs.xxfs), then change the oid number of that node to
344 * match the filesystem's type number. This allows user code
345 * which uses the type number to read sysctl variables defined
346 * by the filesystem to continue working. Since the oids are
347 * in a sorted list, we need to make sure the order is
348 * preserved by re-registering the oid after modifying its
351 SLIST_FOREACH(oidp, &sysctl__vfs_children, oid_link)
352 if (strcmp(oidp->oid_name, vfc->vfc_name) == 0) {
353 sysctl_unregister_oid(oidp);
354 oidp->oid_number = vfc->vfc_typenum;
355 sysctl_register_oid(oidp);
359 * Call init function for this VFS...
361 (*(vfc->vfc_vfsops->vfs_init))(vfc);
367 /* Remove registration of a file system type */
369 vfs_unregister(struct vfsconf *vfc)
371 struct vfsconf *vfsp, *prev_vfsp;
372 int error, i, maxtypenum;
374 i = vfc->vfc_typenum;
377 for (vfsp = vfsconf; vfsp;
378 prev_vfsp = vfsp, vfsp = vfsp->vfc_next) {
379 if (!strcmp(vfc->vfc_name, vfsp->vfc_name))
384 if (vfsp->vfc_refcount)
386 if (vfc->vfc_vfsops->vfs_uninit != NULL) {
387 error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp);
392 prev_vfsp->vfc_next = vfsp->vfc_next;
394 vfsconf = vfsp->vfc_next;
395 maxtypenum = VFS_GENERIC;
396 for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next)
397 if (maxtypenum < vfsp->vfc_typenum)
398 maxtypenum = vfsp->vfc_typenum;
399 maxvfsconf = maxtypenum + 1;
404 * Standard kernel module handling code for file system modules.
405 * Referenced from VFS_SET().
408 vfs_modevent(module_t mod, int type, void *data)
413 vfc = (struct vfsconf *)data;
418 error = vfs_register(vfc);
423 error = vfs_unregister(vfc);
425 default: /* including MOD_SHUTDOWN */