/*      $OpenBSD: nfs_node.c,v 1.77 2026/06/30 14:04:04 kirill Exp $    */
/*      $NetBSD: nfs_node.c,v 1.16 1996/02/18 11:53:42 fvdl Exp $       */

/*
 * Copyright (c) 1989, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * 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. 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.
 *
 *      @(#)nfs_node.c  8.6 (Berkeley) 5/22/95
 */


#include <sys/param.h>
#include <sys/systm.h>
#include <sys/timeout.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/pool.h>
#include <sys/rwlock.h>

#include <nfs/nfsproto.h>
#include <nfs/nfsnode.h>
#include <nfs/nfsmount.h>
#include <nfs/nfs_var.h>

struct pool nfs_node_pool;
extern int prtactive;

/* XXX */
extern const struct vops nfs_vops;

/* filehandle to node lookup. */
static __inline int
nfsnode_cmp(const struct nfsnode *a, const struct nfsnode *b)
{
        if (a->n_fhsize != b->n_fhsize)
                return (a->n_fhsize - b->n_fhsize);
        return (memcmp(a->n_fhp, b->n_fhp, a->n_fhsize));
}

RBT_PROTOTYPE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
RBT_GENERATE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);

void
nfs_ninit(struct nfsmount *nmp)
{
        RBT_INIT(nfs_nodetree, &nmp->nm_ntree);
}

/*
 * Look up a vnode/nfsnode by file handle and store the pointer in *npp.
 * Callers must check for mount points!!
 * An error number is returned.
 */
int
nfs_nget(struct mount *mnt, nfsfh_t *fh, int fhsize, struct nfsnode **npp)
{
        struct nfsmount         *nmp;
        struct nfsnode          *np, find, *np2;
        struct vnode            *vp, *nvp;
        u_int                    vpid;
        int                      error;

        nmp = VFSTONFS(mnt);

loop:
        find.n_fhp = fh;
        find.n_fhsize = fhsize;
        np = RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
        if (np != NULL) {
                vp = NFSTOV(np);
                vpid = vp->v_id;
                error = vget(vp, LK_EXCLUSIVE);
                if (error)
                        goto loop;
                if (vpid != vp->v_id) {
                        vput(vp);
                        goto loop;
                }
                *npp = np;
                return (0);
        }

        /*
         * getnewvnode() could recycle a vnode, potentially formerly
         * owned by NFS. This will cause a VOP_RECLAIM() to happen,
         * which will cause recursive locking, so we unlock before
         * calling getnewvnode() lock again afterwards, but must check
         * to see if this nfsnode has been added while we did not hold
         * the lock.
         */
        error = getnewvnode(VT_NFS, mnt, &nfs_vops, &nvp);
        /* note that we don't have this vnode set up completely yet */
        if (error) {
                *npp = NULL;
                return (error);
        }
        nvp->v_flag |= VLARVAL;
        np = pool_get(&nfs_node_pool, PR_WAITOK | PR_ZERO);
        /*
         * getnewvnode() and pool_get() can sleep, check for race.
         */
        if (RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find) != NULL) {
                pool_put(&nfs_node_pool, np);
                vgone(nvp);
                goto loop;
        }

        vp = nvp;
#ifdef VFSLCKDEBUG
        vp->v_flag |= VLOCKSWORK;
#endif
        rrw_init_flags(&np->n_lock, "nfsnode", RWL_DUPOK | RWL_IS_VNODE);
        vp->v_data = np;
        /* we now have an nfsnode on this vnode */
        vp->v_flag &= ~VLARVAL;
        np->n_vnode = vp;
        rw_init(&np->n_commitlock, "nfs_commitlk");
        np->n_fhp = &np->n_fh;
        bcopy(fh, np->n_fhp, fhsize);
        np->n_fhsize = fhsize;
        /* lock the nfsnode, then put it on the rbtree */
        VOP_LOCK(vp, LK_EXCLUSIVE);
        np2 = RBT_INSERT(nfs_nodetree, &nmp->nm_ntree, np);
        KASSERT(np2 == NULL);
        np->n_accstamp = -1;
        *npp = np;

        return (0);
}

int
nfs_inactive(void *v)
{
        struct vop_inactive_args        *ap = v;
        struct nfsnode                  *np;
        struct sillyrename              *sp;

#ifdef DIAGNOSTIC
        if (prtactive && ap->a_vp->v_usecount != 0)
                vprint("nfs_inactive: pushing active", ap->a_vp);
#endif
        if (ap->a_vp->v_flag & VLARVAL)
                /*
                 * vnode was incompletely set up, just return
                 * as we are throwing it away.
                 */
                return(0);
#ifdef DIAGNOSTIC
        if (ap->a_vp->v_data == NULL)
                panic("NULL v_data (no nfsnode set up?) in vnode %p",
                    ap->a_vp);
#endif
        np = VTONFS(ap->a_vp);
        if (ap->a_vp->v_type != VDIR) {
                sp = np->n_sillyrename;
                np->n_sillyrename = NULL;
        } else
                sp = NULL;
        if (sp != NULL)
                nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, curproc);
        np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT);

        VOP_UNLOCK(ap->a_vp);

        if (sp != NULL) {
                /*
                 * Remove the silly file that was rename'd earlier
                 */
                vn_lock(sp->s_dvp, LK_EXCLUSIVE | LK_RETRY);
                nfs_removeit(sp);
                crfree(sp->s_cred);
                vput(sp->s_dvp);
                free(sp, M_NFSREQ, sizeof(*sp));
        }

        return (0);
}

/*
 * Reclaim an nfsnode so that it can be used for other purposes.
 */
int
nfs_reclaim(void *v)
{
        struct vop_reclaim_args *ap = v;
        struct vnode            *vp = ap->a_vp;
        struct nfsmount         *nmp;
        struct nfsnode          *np = VTONFS(vp);

#ifdef DIAGNOSTIC
        if (prtactive && vp->v_usecount != 0)
                vprint("nfs_reclaim: pushing active", vp);
#endif
        if (ap->a_vp->v_flag & VLARVAL)
                /*
                 * vnode was incompletely set up, just return
                 * as we are throwing it away.
                 */
                return(0);
#ifdef DIAGNOSTIC
        if (ap->a_vp->v_data == NULL)
                panic("NULL v_data (no nfsnode set up?) in vnode %p",
                    ap->a_vp);
#endif
        nmp = VFSTONFS(vp->v_mount);
        RBT_REMOVE(nfs_nodetree, &nmp->nm_ntree, np);

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

        cache_purge(vp);
        pool_put(&nfs_node_pool, vp->v_data);
        vp->v_data = NULL;

        return (0);
}