/*	$NetBSD$	*/

/*-
 * Copyright (c) 2014 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Taylor R Campbell.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

/*
 * XXX NOTE NOTE NOTE XXX
 *
 * This code does not actually work.  It is a draft of an idea.  It
 * probably won't even compile, even if you make it include the right
 * header files.
 */

int
nfs_nget(struct mount *mp, nfsfh_t *fhp, int fhsize, struct nfsnode *npp,
    int flags)
{
	struct vnode *vp = NULL, *vp0 = NULL;
	static const struct nfsnode zero_nfsnode;
	struct nfsnode *np;
	int error;

	/*
	 * Try to get an existing vnode for this file handle.
	 */
	error = vinotab_get(nmp->nm_vinotab, fhp, fhsize, VWAIT_INTR, &vp);
	KASSERT((error == 0) == (vp != NULL));
	if (error != ENOENT)
		goto out;

	/*
	 * Create a new vnode for it instead.
	 */
	error = getnewvnode(VT_NFS, mp, nfsv2_vnodeop_p, NULL, &vp);
	KASSERT((error == 0) == (vp != NULL));
	if (error)
		goto out;

	/*
	 * Create an nfsnode structure for it and fill it in just
	 * enough for a lookup.
	 */
	np = pool_get(&nfs_node_pool, PR_WAITOK);
	KASSERT(np != NULL);
	*np = zero_nfsnode;

	if (fhsize > NFS_SMALLFH)
		np->n_fhp = kmem_alloc(fhsize, KM_SLEEP);
	else
		np->n_fhp = &np->n_fh;
	(void)memcpy(np->n_fhp, fhp, fhsize);
	np->n_fhsize = fhsize;

	/*
	 * Try to put this vnode in the table for the file handle.  If
	 * someone else beat us to it, release ours and use theirs
	 * instead.
	 */
	error = vinotab_intern(nmp->nm_vinotab, &np->n_vinoent, np->n_fhp,
	    np->n_fhsize, vp, VWAIT_INTR, &vp0);
	KASSERT((error == 0) == (vp0 != NULL));
	if (vp0 != vp) {
		if (fhsize > NFS_SMALLFH)
			kmem_free(np->n_fhp, np->n_fhsize);
		pool_put(&nfs_node_pool, np);
		ungetnewvnode(vp);
		vp = vp0;
		goto out;
	}

	/*
	 * Initialize the new vnode and nfsnode.
	 */
	vp->v_data = np;
	genfs_node_init(vp, &nfs_genfsops);

	np->n_accstamp = -1;
	np->n_vattr = pool_get(&nfs_vattr_pool, PR_WAITOK);
	np->n_rcred = curlwp->l_cred;
	kauth_cred_hold(np->n_rcred);
	np->n_wcred = curlwp->l_cred;
	kauth_cred_hold(np->n_wcred);

	/*
	 * Invalidate the attribute cache so that anyone trying to get
	 * the size will caues it to be filled in.  Pretend the size is
	 * zero for now (XXX why?).
	 */
	NFS_INVALIDATE_ATTRCACHE(np);
	uvm_vnp_setsize(vp, 0);

	/*
	 * All set.  Mark it ready to go and wake anyone waiting.
	 */
	vready(vp);
	error = 0;

out:	*npp = (vp == NULL? NULL : vp->v_data);
	return error;
}

int
nfs_reclaim(void *v)
{
	struct vop_destroy_args /* {
		struct vnode *a_vp;
	} */ *ap = v;
	struct vnode *vp = ap->a_vp;
	struct nfsnode *np = VTONFS(vp);
	struct nfsmount *nmp = VFSTONFS(vp->v_mount);

	vinotab_remove(nmp->nm_vinotab, &np->n_vinoent);

	switch (vp->v_type) {
	case VREG:
		mutex_destroy(&np->n_commitlock);
		break;
	case VDIR:
		if (np->n_dircache == NULL)
			break;
		nfs_invaldircache(vp, NFS_INVALDIRCACHE_FORCE);
		hashdone(np->n_dircache, HASH_LIST, nfsdirhashmask);
		break;
	}
	KASSERT(np->n_dirgens == NULL);

	if (np->n_wcred)
		kauth_cred_free(np->n_wcred);
	if (np->n_rcred)
		kauth_cred_free(np->n_rcred);

	pool_put(&nfs_vattr_pool, np->n_vattr);

	genfs_node_destroy(vp);
	vp->v_data = NULL;

	if (np->n_fhsize > NFS_SMALLFH)
		kmem_free(np->n_fhp, np->n_fhsize);
	pool_put(&nfs_node_pool, np);

	return 0;
}