freebsd-dev/sys/kern/vfs_init.c
Bruce Evans e99ea9ec2b Ignore the statically configured vfs type numbers and assign vfs
type numbers in vfs attach order (modulo incomplete reuse of old
numbers after vfs LKMs are unloaded).  This requires reinitializing
the sysctl tree (or at least the vfs subtree) for vfs's that support
sysctls (currently only nfs).  sysctl_order() already handled
reinitialization reasonably except it checked for annulled self
references in the wrong place.

Fixed sysctls for vfs LKMs.
1998-09-05 17:13:28 +00:00

271 lines
8.3 KiB
C

/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed
* to Berkeley by John Heidemann of the UCLA Ficus project.
*
* Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)vfs_init.c 8.3 (Berkeley) 1/4/94
* $Id: vfs_init.c,v 1.32 1998/02/09 06:09:33 eivind Exp $
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/sysctl.h>
#include <sys/vnode.h>
#include <sys/malloc.h>
#include <vm/vm_zone.h>
static void vfs_op_init __P((void));
static void vfsinit __P((void *));
SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL)
MALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes");
/*
* Sigh, such primitive tools are these...
*/
#if 0
#define DODEBUG(A) A
#else
#define DODEBUG(A)
#endif
static struct vfsconf void_vfsconf;
extern struct linker_set vfs_opv_descs_;
#define vfs_opv_descs ((struct vnodeopv_desc **)vfs_opv_descs_.ls_items)
extern struct linker_set vfs_set;
extern struct vnodeop_desc *vfs_op_descs[];
/* and the operations they perform */
/*
* Zone for namei
*/
struct vm_zone *namei_zone;
/*
* vfs_init.c
*
* Allocate and fill in operations vectors.
*
* An undocumented feature of this approach to defining operations is that
* there can be multiple entries in vfs_opv_descs for the same operations
* vector. This allows third parties to extend the set of operations
* supported by another layer in a binary compatibile way. For example,
* assume that NFS needed to be modified to support Ficus. NFS has an entry
* (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by
* default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions)
* listing those new operations Ficus adds to NFS, all without modifying the
* NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but
* that is a(whole)nother story.) This is a feature.
*
* Without an explicit reserve area, however, you must replace vnode_if.c
* and vnode_if.h when you do this, or you will be derefrencing of the
* end of vfs_op_descs[]. This is a flaw in the use of a structure
* pointer array rather than an agregate to define vfs_op_descs. So
* it's not a very dynamic "feature".
*/
void
vfs_opv_init(struct vnodeopv_desc **them)
{
int i, j, k;
vop_t ***opv_desc_vector_p;
vop_t **opv_desc_vector;
struct vnodeopv_entry_desc *opve_descp;
/*
* Allocate the dynamic vectors and fill them in.
*/
for (i=0; them[i]; i++) {
opv_desc_vector_p = them[i]->opv_desc_vector_p;
/*
* Allocate and init the vector, if it needs it.
* Also handle backwards compatibility.
*/
if (*opv_desc_vector_p == NULL) {
/* XXX - shouldn't be M_VNODE */
MALLOC(*opv_desc_vector_p, vop_t **,
vfs_opv_numops * sizeof(vop_t *), M_VNODE,
M_WAITOK);
bzero(*opv_desc_vector_p,
vfs_opv_numops * sizeof(vop_t *));
DODEBUG(printf("vector at %x allocated\n",
opv_desc_vector_p));
}
opv_desc_vector = *opv_desc_vector_p;
for (j=0; them[i]->opv_desc_ops[j].opve_op; j++) {
opve_descp = &(them[i]->opv_desc_ops[j]);
/*
* Sanity check: is this operation listed
* in the list of operations? We check this
* by seeing if its offest is zero. Since
* the default routine should always be listed
* first, it should be the only one with a zero
* offset. Any other operation with a zero
* offset is probably not listed in
* vfs_op_descs, and so is probably an error.
*
* A panic here means the layer programmer
* has committed the all-too common bug
* of adding a new operation to the layer's
* list of vnode operations but
* not adding the operation to the system-wide
* list of supported operations.
*/
if (opve_descp->opve_op->vdesc_offset == 0 &&
opve_descp->opve_op->vdesc_offset !=
VOFFSET(vop_default)) {
printf("operation %s not listed in %s.\n",
opve_descp->opve_op->vdesc_name,
"vfs_op_descs");
panic ("vfs_opv_init: bad operation");
}
/*
* Fill in this entry.
*/
opv_desc_vector[opve_descp->opve_op->vdesc_offset] =
opve_descp->opve_impl;
}
}
/*
* Finally, go back and replace unfilled routines
* with their default. (Sigh, an O(n^3) algorithm. I
* could make it better, but that'd be work, and n is small.)
*/
for (i = 0; them[i]; i++) {
opv_desc_vector = *(them[i]->opv_desc_vector_p);
/*
* Force every operations vector to have a default routine.
*/
if (opv_desc_vector[VOFFSET(vop_default)]==NULL) {
panic("vfs_opv_init: operation vector without default routine.");
}
for (k = 0; k<vfs_opv_numops; k++)
if (opv_desc_vector[k] == NULL)
opv_desc_vector[k] =
opv_desc_vector[VOFFSET(vop_default)];
}
}
/*
* Initialize known vnode operations vectors.
*/
static void
vfs_op_init()
{
int i;
DODEBUG(printf("Vnode_interface_init.\n"));
DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops));
/*
* Set all vnode vectors to a well known value.
*/
for (i = 0; vfs_opv_descs[i]; i++)
*(vfs_opv_descs[i]->opv_desc_vector_p) = NULL;
/*
* assign each op to its offset
*
* XXX This should not be needed, but is because the per
* XXX FS ops tables are not sorted according to the
* XXX vnodeop_desc's offset in vfs_op_descs. This
* XXX is the same reason we have to take the hit for
* XXX the static inline function calls instead of using
* XXX simple macro references.
*/
for (i = 0; i < vfs_opv_numops; i++)
vfs_op_descs[i]->vdesc_offset = i;
}
/*
* Routines having to do with the management of the vnode table.
*/
extern struct vnodeops dead_vnodeops;
extern struct vnodeops spec_vnodeops;
struct vattr va_null;
/*
* Initialize the vnode structures and initialize each file system type.
*/
/* ARGSUSED*/
static void
vfsinit(dummy)
void *dummy;
{
struct vfsconf **vfc, *vfsp;
int maxtypenum;
namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2);
/*
* Initialize the vnode table
*/
vntblinit();
/*
* Initialize the vnode name cache
*/
nchinit();
/*
* Build vnode operation vectors.
*/
vfs_op_init();
vfs_opv_init(vfs_opv_descs); /* finish the job */
/*
* Initialize each file system type.
*/
vattr_null(&va_null);
maxtypenum = 0;
vfc = (struct vfsconf **)vfs_set.ls_items;
vfsconf = *vfc;
for (; *vfc != NULL; maxtypenum++, vfc++) {
vfsp = *vfc;
vfsp->vfc_next = *(vfc + 1);
vfsp->vfc_typenum = maxtypenum;
if (vfsp->vfc_vfsops->vfs_oid != NULL) {
vfsp->vfc_vfsops->vfs_oid->oid_number = maxtypenum;
sysctl_order_all();
}
(*vfsp->vfc_vfsops->vfs_init)(vfsp);
}
/* next vfc_typenum to be used */
maxvfsconf = maxtypenum;
}