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diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c
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+/*
+ * 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.
+ *
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/unistd.h>
+#include <sys/vnode.h>
+#include <sys/poll.h>
+
+static int vop_nostrategy __P((struct vop_strategy_args *));
+
+/*
+ * This vnode table stores what we want to do if the filesystem doesn't
+ * implement a particular VOP.
+ *
+ * If there is no specific entry here, we will return EOPNOTSUPP.
+ *
+ */
+
+vop_t **default_vnodeop_p;
+static struct vnodeopv_entry_desc default_vnodeop_entries[] = {
+ { &vop_default_desc, (vop_t *) vop_eopnotsupp },
+ { &vop_abortop_desc, (vop_t *) vop_null },
+ { &vop_advlock_desc, (vop_t *) vop_einval },
+ { &vop_bwrite_desc, (vop_t *) vop_stdbwrite },
+ { &vop_close_desc, (vop_t *) vop_null },
+ { &vop_fsync_desc, (vop_t *) vop_null },
+ { &vop_ioctl_desc, (vop_t *) vop_enotty },
+ { &vop_islocked_desc, (vop_t *) vop_noislocked },
+ { &vop_lease_desc, (vop_t *) vop_null },
+ { &vop_lock_desc, (vop_t *) vop_nolock },
+ { &vop_mmap_desc, (vop_t *) vop_einval },
+ { &vop_open_desc, (vop_t *) vop_null },
+ { &vop_pathconf_desc, (vop_t *) vop_einval },
+ { &vop_poll_desc, (vop_t *) vop_nopoll },
+ { &vop_readlink_desc, (vop_t *) vop_einval },
+ { &vop_reallocblks_desc, (vop_t *) vop_eopnotsupp },
+ { &vop_revoke_desc, (vop_t *) vop_revoke },
+ { &vop_strategy_desc, (vop_t *) vop_nostrategy },
+ { &vop_unlock_desc, (vop_t *) vop_nounlock },
+ { NULL, NULL }
+};
+
+static struct vnodeopv_desc default_vnodeop_opv_desc =
+ { &default_vnodeop_p, default_vnodeop_entries };
+
+VNODEOP_SET(default_vnodeop_opv_desc);
+
+int
+vop_eopnotsupp(struct vop_generic_args *ap)
+{
+ /*
+ printf("vop_notsupp[%s]\n", ap->a_desc->vdesc_name);
+ */
+
+ return (EOPNOTSUPP);
+}
+
+int
+vop_ebadf(struct vop_generic_args *ap)
+{
+
+ return (EBADF);
+}
+
+int
+vop_enotty(struct vop_generic_args *ap)
+{
+
+ return (ENOTTY);
+}
+
+int
+vop_einval(struct vop_generic_args *ap)
+{
+
+ return (EINVAL);
+}
+
+int
+vop_null(struct vop_generic_args *ap)
+{
+
+ return (0);
+}
+
+int
+vop_defaultop(struct vop_generic_args *ap)
+{
+
+ return (VOCALL(default_vnodeop_p, ap->a_desc->vdesc_offset, ap));
+}
+
+int
+vop_panic(struct vop_generic_args *ap)
+{
+
+ panic("illegal vnode op called");
+}
+
+static int
+vop_nostrategy (struct vop_strategy_args *ap)
+{
+ printf("No strategy for buffer at %p\n", ap->a_bp);
+ vprint("", ap->a_vp);
+ vprint("", ap->a_bp->b_vp);
+ ap->a_bp->b_flags |= B_ERROR;
+ ap->a_bp->b_error = EOPNOTSUPP;
+ biodone(ap->a_bp);
+ return (EOPNOTSUPP);
+}
+
+int
+vop_stdpathconf(ap)
+ struct vop_pathconf_args /* {
+ struct vnode *a_vp;
+ int a_name;
+ int *a_retval;
+ } */ *ap;
+{
+
+ switch (ap->a_name) {
+ case _PC_LINK_MAX:
+ *ap->a_retval = LINK_MAX;
+ return (0);
+ case _PC_MAX_CANON:
+ *ap->a_retval = MAX_CANON;
+ return (0);
+ case _PC_MAX_INPUT:
+ *ap->a_retval = MAX_INPUT;
+ return (0);
+ case _PC_PIPE_BUF:
+ *ap->a_retval = PIPE_BUF;
+ return (0);
+ case _PC_CHOWN_RESTRICTED:
+ *ap->a_retval = 1;
+ return (0);
+ case _PC_VDISABLE:
+ *ap->a_retval = _POSIX_VDISABLE;
+ return (0);
+ default:
+ return (EINVAL);
+ }
+ /* NOTREACHED */
+}
+
+/*
+ * Standard lock, unlock and islocked functions.
+ *
+ * These depend on the lock structure being the first element in the
+ * inode, ie: vp->v_data points to the the lock!
+ */
+int
+vop_stdlock(ap)
+ struct vop_lock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+ struct lock *l;
+
+ if ((l = (struct lock *)ap->a_vp->v_data) == NULL) {
+ if (ap->a_flags & LK_INTERLOCK)
+ simple_unlock(&ap->a_vp->v_interlock);
+ return 0;
+ }
+
+#ifndef DEBUG_LOCKS
+ return (lockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p));
+#else
+ return (debuglockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p,
+ "vop_stdlock", ap->a_vp->filename, ap->a_vp->line));
+#endif
+}
+
+int
+vop_stdunlock(ap)
+ struct vop_unlock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+ struct lock *l;
+
+ if ((l = (struct lock *)ap->a_vp->v_data) == NULL) {
+ if (ap->a_flags & LK_INTERLOCK)
+ simple_unlock(&ap->a_vp->v_interlock);
+ return 0;
+ }
+
+ return (lockmgr(l, ap->a_flags | LK_RELEASE, &ap->a_vp->v_interlock,
+ ap->a_p));
+}
+
+int
+vop_stdislocked(ap)
+ struct vop_islocked_args /* {
+ struct vnode *a_vp;
+ } */ *ap;
+{
+ struct lock *l;
+
+ if ((l = (struct lock *)ap->a_vp->v_data) == NULL)
+ return 0;
+
+ return (lockstatus(l));
+}
+
+/*
+ * Return true for select/poll.
+ */
+int
+vop_nopoll(ap)
+ struct vop_poll_args /* {
+ struct vnode *a_vp;
+ int a_events;
+ struct ucred *a_cred;
+ struct proc *a_p;
+ } */ *ap;
+{
+ /*
+ * Return true for read/write. If the user asked for something
+ * special, return POLLNVAL, so that clients have a way of
+ * determining reliably whether or not the extended
+ * functionality is present without hard-coding knowledge
+ * of specific filesystem implementations.
+ */
+ if (ap->a_events & ~POLLSTANDARD)
+ return (POLLNVAL);
+
+ return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
+}
+
+/*
+ * Implement poll for local filesystems that support it.
+ */
+int
+vop_stdpoll(ap)
+ struct vop_poll_args /* {
+ struct vnode *a_vp;
+ int a_events;
+ struct ucred *a_cred;
+ struct proc *a_p;
+ } */ *ap;
+{
+ if ((ap->a_events & ~POLLSTANDARD) == 0)
+ return (ap->a_events & (POLLRDNORM|POLLWRNORM));
+ return (vn_pollrecord(ap->a_vp, ap->a_p, ap->a_events));
+}
+
+int
+vop_stdbwrite(ap)
+ struct vop_bwrite_args *ap;
+{
+ return (bwrite(ap->a_bp));
+}
+
+/*
+ * Stubs to use when there is no locking to be done on the underlying object.
+ * A minimal shared lock is necessary to ensure that the underlying object
+ * is not revoked while an operation is in progress. So, an active shared
+ * count is maintained in an auxillary vnode lock structure.
+ */
+int
+vop_sharedlock(ap)
+ struct vop_lock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+ /*
+ * This code cannot be used until all the non-locking filesystems
+ * (notably NFS) are converted to properly lock and release nodes.
+ * Also, certain vnode operations change the locking state within
+ * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
+ * and symlink). Ideally these operations should not change the
+ * lock state, but should be changed to let the caller of the
+ * function unlock them. Otherwise all intermediate vnode layers
+ * (such as union, umapfs, etc) must catch these functions to do
+ * the necessary locking at their layer. Note that the inactive
+ * and lookup operations also change their lock state, but this
+ * cannot be avoided, so these two operations will always need
+ * to be handled in intermediate layers.
+ */
+ struct vnode *vp = ap->a_vp;
+ int vnflags, flags = ap->a_flags;
+
+ if (vp->v_vnlock == NULL) {
+ if ((flags & LK_TYPE_MASK) == LK_DRAIN)
+ return (0);
+ MALLOC(vp->v_vnlock, struct lock *, sizeof(struct lock),
+ M_VNODE, M_WAITOK);
+ lockinit(vp->v_vnlock, PVFS, "vnlock", 0, LK_NOPAUSE);
+ }
+ switch (flags & LK_TYPE_MASK) {
+ case LK_DRAIN:
+ vnflags = LK_DRAIN;
+ break;
+ case LK_EXCLUSIVE:
+#ifdef DEBUG_VFS_LOCKS
+ /*
+ * Normally, we use shared locks here, but that confuses
+ * the locking assertions.
+ */
+ vnflags = LK_EXCLUSIVE;
+ break;
+#endif
+ case LK_SHARED:
+ vnflags = LK_SHARED;
+ break;
+ case LK_UPGRADE:
+ case LK_EXCLUPGRADE:
+ case LK_DOWNGRADE:
+ return (0);
+ case LK_RELEASE:
+ default:
+ panic("vop_sharedlock: bad operation %d", flags & LK_TYPE_MASK);
+ }
+ if (flags & LK_INTERLOCK)
+ vnflags |= LK_INTERLOCK;
+#ifndef DEBUG_LOCKS
+ return (lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
+#else
+ return (debuglockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p,
+ "vop_sharedlock", vp->filename, vp->line));
+#endif
+}
+
+/*
+ * Stubs to use when there is no locking to be done on the underlying object.
+ * A minimal shared lock is necessary to ensure that the underlying object
+ * is not revoked while an operation is in progress. So, an active shared
+ * count is maintained in an auxillary vnode lock structure.
+ */
+int
+vop_nolock(ap)
+ struct vop_lock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+#ifdef notyet
+ /*
+ * This code cannot be used until all the non-locking filesystems
+ * (notably NFS) are converted to properly lock and release nodes.
+ * Also, certain vnode operations change the locking state within
+ * the operation (create, mknod, remove, link, rename, mkdir, rmdir,
+ * and symlink). Ideally these operations should not change the
+ * lock state, but should be changed to let the caller of the
+ * function unlock them. Otherwise all intermediate vnode layers
+ * (such as union, umapfs, etc) must catch these functions to do
+ * the necessary locking at their layer. Note that the inactive
+ * and lookup operations also change their lock state, but this
+ * cannot be avoided, so these two operations will always need
+ * to be handled in intermediate layers.
+ */
+ struct vnode *vp = ap->a_vp;
+ int vnflags, flags = ap->a_flags;
+
+ if (vp->v_vnlock == NULL) {
+ if ((flags & LK_TYPE_MASK) == LK_DRAIN)
+ return (0);
+ MALLOC(vp->v_vnlock, struct lock *, sizeof(struct lock),
+ M_VNODE, M_WAITOK);
+ lockinit(vp->v_vnlock, PVFS, "vnlock", 0, LK_NOPAUSE);
+ }
+ switch (flags & LK_TYPE_MASK) {
+ case LK_DRAIN:
+ vnflags = LK_DRAIN;
+ break;
+ case LK_EXCLUSIVE:
+ case LK_SHARED:
+ vnflags = LK_SHARED;
+ break;
+ case LK_UPGRADE:
+ case LK_EXCLUPGRADE:
+ case LK_DOWNGRADE:
+ return (0);
+ case LK_RELEASE:
+ default:
+ panic("vop_nolock: bad operation %d", flags & LK_TYPE_MASK);
+ }
+ if (flags & LK_INTERLOCK)
+ vnflags |= LK_INTERLOCK;
+ return(lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
+#else /* for now */
+ /*
+ * Since we are not using the lock manager, we must clear
+ * the interlock here.
+ */
+ if (ap->a_flags & LK_INTERLOCK)
+ simple_unlock(&ap->a_vp->v_interlock);
+ return (0);
+#endif
+}
+
+/*
+ * Do the inverse of vop_nolock, handling the interlock in a compatible way.
+ */
+int
+vop_nounlock(ap)
+ struct vop_unlock_args /* {
+ struct vnode *a_vp;
+ int a_flags;
+ struct proc *a_p;
+ } */ *ap;
+{
+ struct vnode *vp = ap->a_vp;
+
+ if (vp->v_vnlock == NULL) {
+ if (ap->a_flags & LK_INTERLOCK)
+ simple_unlock(&ap->a_vp->v_interlock);
+ return (0);
+ }
+ return (lockmgr(vp->v_vnlock, LK_RELEASE | ap->a_flags,
+ &ap->a_vp->v_interlock, ap->a_p));
+}
+
+/*
+ * Return whether or not the node is in use.
+ */
+int
+vop_noislocked(ap)
+ struct vop_islocked_args /* {
+ struct vnode *a_vp;
+ } */ *ap;
+{
+ struct vnode *vp = ap->a_vp;
+
+ if (vp->v_vnlock == NULL)
+ return (0);
+ return (lockstatus(vp->v_vnlock));
+}
+
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