示例#1
0
/*
 * Initialize this vnode / nfs node pair.
 * Caller assures no other thread will try to load this node.
 */
int
nfs_loadvnode(struct mount *mp, struct vnode *vp,
    const void *key, size_t key_len, const void **new_key)
{
	int fhsize = key_len;
	const nfsfh_t *fhp = key;
	struct nfsnode *np;

	/* Aloocate and initialize the nfsnode. */
	np = pool_get(&nfs_node_pool, PR_WAITOK);
	memset(np, 0, sizeof *np);
	if (fhsize > NFS_SMALLFH) {
		np->n_fhp = kmem_alloc(fhsize, KM_SLEEP);
	} else
		np->n_fhp = &np->n_fh;
	vp->v_tag = VT_NFS;
	vp->v_type = VNON;
	vp->v_op = nfsv2_vnodeop_p;
	vp->v_data = np;
	memcpy(np->n_fhp, fhp, fhsize);
	np->n_fhsize = fhsize;
	np->n_accstamp = -1;
	np->n_vattr = pool_get(&nfs_vattr_pool, PR_WAITOK);
	np->n_vnode = vp;

	/* Initialize genfs node. */
	genfs_node_init(vp, &nfs_genfsops);
	/*
	 * Initalize read/write creds to useful values. VOP_OPEN will
	 * overwrite these.
	 */
	np->n_rcred = curlwp->l_cred;
	kauth_cred_hold(np->n_rcred);
	np->n_wcred = curlwp->l_cred;
	kauth_cred_hold(np->n_wcred);
	NFS_INVALIDATE_ATTRCACHE(np);
	uvm_vnp_setsize(vp, 0);
	*new_key = np->n_fhp;
	return 0;
}
/*
 * Look up a vnode/nfsnode by file handle.
 * Callers must check for mount points!!
 * In all cases, a pointer to a
 * nfsnode structure is returned.
 */
int
nfs_nget1(struct mount *mntp, nfsfh_t *fhp, int fhsize, struct nfsnode **npp,
    int lkflags)
{
	struct nfsnode *np;
	struct vnode *vp;
	struct nfsmount *nmp = VFSTONFS(mntp);
	int error;
	struct fh_match fhm;

	fhm.fhm_fhp = fhp;
	fhm.fhm_fhsize = fhsize;

loop:
	rw_enter(&nmp->nm_rbtlock, RW_READER);
	np = rb_tree_find_node(&nmp->nm_rbtree, &fhm);
	if (np != NULL) {
		vp = NFSTOV(np);
		mutex_enter(vp->v_interlock);
		rw_exit(&nmp->nm_rbtlock);
		error = vget(vp, LK_EXCLUSIVE | lkflags);
		if (error == EBUSY)
			return error;
		if (error)
			goto loop;
		*npp = np;
		return(0);
	}
	rw_exit(&nmp->nm_rbtlock);

	error = getnewvnode(VT_NFS, mntp, nfsv2_vnodeop_p, NULL, &vp);
	if (error) {
		*npp = 0;
		return (error);
	}
	np = pool_get(&nfs_node_pool, PR_WAITOK);
	memset(np, 0, sizeof *np);
	np->n_vnode = vp;

	/*
	 * Insert the nfsnode in the hash queue for its new file handle
	 */

	if (fhsize > NFS_SMALLFH) {
		np->n_fhp = kmem_alloc(fhsize, KM_SLEEP);
	} else
		np->n_fhp = &np->n_fh;
	memcpy(np->n_fhp, fhp, fhsize);
	np->n_fhsize = fhsize;
	np->n_accstamp = -1;
	np->n_vattr = pool_get(&nfs_vattr_pool, PR_WAITOK);

	rw_enter(&nmp->nm_rbtlock, RW_WRITER);
	if (NULL != rb_tree_find_node(&nmp->nm_rbtree, &fhm)) {
		rw_exit(&nmp->nm_rbtlock);
		if (fhsize > NFS_SMALLFH) {
			kmem_free(np->n_fhp, fhsize);
		}
		pool_put(&nfs_vattr_pool, np->n_vattr);
		pool_put(&nfs_node_pool, np);
		ungetnewvnode(vp);
		goto loop;
	}
	vp->v_data = np;
	genfs_node_init(vp, &nfs_genfsops);
	/*
	 * Initalize read/write creds to useful values. VOP_OPEN will
	 * overwrite these.
	 */
	np->n_rcred = curlwp->l_cred;
	kauth_cred_hold(np->n_rcred);
	np->n_wcred = curlwp->l_cred;
	kauth_cred_hold(np->n_wcred);
	VOP_LOCK(vp, LK_EXCLUSIVE);
	NFS_INVALIDATE_ATTRCACHE(np);
	uvm_vnp_setsize(vp, 0);
	(void)rb_tree_insert_node(&nmp->nm_rbtree, np);
	rw_exit(&nmp->nm_rbtlock);

	*npp = np;
	return (0);
}