xref: /src/sys/miscfs/genfs/genfs_vnops.c

/*	$NetBSD: genfs_vnops.c,v 1.18 2000/05/29 18:59:51 mycroft Exp $	*/

/*
 * Copyright (c) 1982, 1986, 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * 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 "opt_nfsserver.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/fcntl.h>
#include <sys/malloc.h>
#include <sys/poll.h>

#include <miscfs/genfs/genfs.h>
#include <miscfs/specfs/specdev.h>

#ifdef NFSSERVER
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nqnfs.h>
#include <nfs/nfs_var.h>
#endif

int
genfs_poll(v)
	void *v;
{
	struct vop_poll_args /* {
		struct vnode *a_vp;
		int a_events;
		struct proc *a_p;
	} */ *ap = v;

	return (ap->a_events & (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM));
}

int
genfs_fsync(v)
	void *v;
{
	struct vop_fsync_args /* {
		struct vnode *a_vp;
		struct ucred *a_cred;
		int a_flags;
		struct proc *a_p;
	} */ *ap = v;
	struct vnode *vp = ap->a_vp;
	int wait;

	wait = (ap->a_flags & FSYNC_WAIT) != 0;
	vflushbuf(vp, wait);
	if ((ap->a_flags & FSYNC_DATAONLY) != 0)
		return (0);
	else
		return (VOP_UPDATE(vp, NULL, NULL, wait ? UPDATE_WAIT : 0));
}

int
genfs_seek(v)
	void *v;
{
	struct vop_seek_args /* {
		struct vnode *a_vp;
		off_t a_oldoff;
		off_t a_newoff;
		struct ucred *a_ucred;
	} */ *ap = v;

	if (ap->a_newoff < 0)
		return (EINVAL);

	return (0);
}

int
genfs_abortop(v)
	void *v;
{
	struct vop_abortop_args /* {
		struct vnode *a_dvp;
		struct componentname *a_cnp;
	} */ *ap = v;

	if ((ap->a_cnp->cn_flags & (HASBUF | SAVESTART)) == HASBUF)
		FREE(ap->a_cnp->cn_pnbuf, M_NAMEI);
	return (0);
}

int
genfs_fcntl(v)
	void *v;
{
	struct vop_fcntl_args /* {
		struct vnode *a_vp;
		u_int a_command;
		caddr_t a_data;
		int a_fflag;
		struct ucred *a_cred;
		struct proc *a_p;
	} */ *ap = v;

	if (ap->a_command == F_SETFL)
		return (0);
	else
		return (EOPNOTSUPP);
}

/*ARGSUSED*/
int
genfs_badop(v)
	void *v;
{

	panic("genfs: bad op");
}

/*ARGSUSED*/
int
genfs_nullop(v)
	void *v;
{

	return (0);
}

/*ARGSUSED*/
int
genfs_einval(v)
	void *v;
{

	return (EINVAL);
}

/*ARGSUSED*/
int
genfs_eopnotsupp(v)
	void *v;
{

	return (EOPNOTSUPP);
}

/*
 * Called when an fs doesn't support a particular vop but the vop needs to
 * vrele, vput, or vunlock passed in vnodes.
 */
int
genfs_eopnotsupp_rele(v)
	void *v;
{
	struct vop_generic_args /*
		struct vnodeop_desc *a_desc;
		/ * other random data follows, presumably * /
	} */ *ap = v;
	struct vnodeop_desc *desc = ap->a_desc;
	struct vnode *vp;
	int flags, i, j, offset;

	flags = desc->vdesc_flags;
	for (i = 0; i < VDESC_MAX_VPS; flags >>=1, i++) {
		if ((offset = desc->vdesc_vp_offsets[i]) == VDESC_NO_OFFSET)
			break;	/* stop at end of list */
		if ((j = flags & VDESC_VP0_WILLPUT)) {
			vp = *VOPARG_OFFSETTO(struct vnode**,offset,ap);
			switch (j) {
			case VDESC_VP0_WILLPUT:
				vput(vp);
				break;
			case VDESC_VP0_WILLUNLOCK:
				VOP_UNLOCK(vp, 0);
				break;
			case VDESC_VP0_WILLRELE:
				vrele(vp);
				break;
			}
		}
	}

	return (EOPNOTSUPP);
}

/*ARGSUSED*/
int
genfs_ebadf(v)
	void *v;
{

	return (EBADF);
}

/* ARGSUSED */
int
genfs_enoioctl(v)
	void *v;
{

	return (ENOTTY);
}


/*
 * Eliminate all activity associated with the requested vnode
 * and with all vnodes aliased to the requested vnode.
 */
int
genfs_revoke(v)
	void *v;
{
	struct vop_revoke_args /* {
		struct vnode *a_vp;
		int a_flags;
	} */ *ap = v;
	struct vnode *vp, *vq;
	struct proc *p = curproc;	/* XXX */

#ifdef DIAGNOSTIC
	if ((ap->a_flags & REVOKEALL) == 0)
		panic("genfs_revoke: not revokeall");
#endif

	vp = ap->a_vp;
	simple_lock(&vp->v_interlock);

	if (vp->v_flag & VALIASED) {
		/*
		 * If a vgone (or vclean) is already in progress,
		 * wait until it is done and return.
		 */
		if (vp->v_flag & VXLOCK) {
			vp->v_flag |= VXWANT;
			simple_unlock(&vp->v_interlock);
			tsleep((caddr_t)vp, PINOD, "vop_revokeall", 0);
			return (0);
		}
		/*
		 * Ensure that vp will not be vgone'd while we
		 * are eliminating its aliases.
		 */
		vp->v_flag |= VXLOCK;
		simple_unlock(&vp->v_interlock);
		while (vp->v_flag & VALIASED) {
			simple_lock(&spechash_slock);
			for (vq = *vp->v_hashchain; vq; vq = vq->v_specnext) {
				if (vq->v_rdev != vp->v_rdev ||
				    vq->v_type != vp->v_type || vp == vq)
					continue;
				simple_unlock(&spechash_slock);
				vgone(vq);
				break;
			}
			if (vq == NULLVP)
				simple_unlock(&spechash_slock);
		}
		/*
		 * Remove the lock so that vgone below will
		 * really eliminate the vnode after which time
		 * vgone will awaken any sleepers.
		 */
		simple_lock(&vp->v_interlock);
		vp->v_flag &= ~VXLOCK;
	}
	vgonel(vp, p);
	return (0);
}

/*
 * Lock the node.
 */
int
genfs_lock(v)
	void *v;
{
	struct vop_lock_args /* {
		struct vnode *a_vp;
		int a_flags;
	} */ *ap = v;
	struct vnode *vp = ap->a_vp;

	return (lockmgr(&vp->v_lock, ap->a_flags, &vp->v_interlock));
}

/*
 * Unlock the node.
 */
int
genfs_unlock(v)
	void *v;
{
	struct vop_unlock_args /* {
		struct vnode *a_vp;
		int a_flags;
	} */ *ap = v;
	struct vnode *vp = ap->a_vp;

	return (lockmgr(&vp->v_lock, ap->a_flags | LK_RELEASE,
		&vp->v_interlock));
}

/*
 * Return whether or not the node is locked.
 */
int
genfs_islocked(v)
	void *v;
{
	struct vop_islocked_args /* {
		struct vnode *a_vp;
	} */ *ap = v;
	struct vnode *vp = ap->a_vp;

	return (lockstatus(&vp->v_lock));
}

/*
 * Stubs to use when there is no locking to be done on the underlying object.
 */
int
genfs_nolock(v)
	void *v;
{
	struct vop_lock_args /* {
		struct vnode *a_vp;
		int a_flags;
		struct proc *a_p;
	} */ *ap = v;

	/*
	 * 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);
}

int
genfs_nounlock(v)
	void *v;
{
	return (0);
}

int
genfs_noislocked(v)
	void *v;
{
	return (0);
}

/*
 * Local lease check for NFS servers.  Just set up args and let
 * nqsrv_getlease() do the rest.  If NFSSERVER is not in the kernel,
 * this is a null operation.
 */
int
genfs_lease_check(v)
	void *v;
{
#ifdef NFSSERVER
	struct vop_lease_args /* {
		struct vnode *a_vp;
		struct proc *a_p;
		struct ucred *a_cred;
		int a_flag;
	} */ *ap = v;
	u_int32_t duration = 0;
	int cache;
	u_quad_t frev;

	(void) nqsrv_getlease(ap->a_vp, &duration, ND_CHECK | ap->a_flag,
	    NQLOCALSLP, ap->a_p, (struct mbuf *)0, &cache, &frev, ap->a_cred);
	return (0);
#else
	return (0);
#endif /* NFSSERVER */
}