X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/060df5ea7c632b1ac8cc8aac1fb59758165c2084..6d2010ae8f7a6078e10b361c6962983bab233e0f:/bsd/miscfs/nullfs/null_subr.c diff --git a/bsd/miscfs/nullfs/null_subr.c b/bsd/miscfs/nullfs/null_subr.c deleted file mode 100644 index d061bb77f..000000000 --- a/bsd/miscfs/nullfs/null_subr.c +++ /dev/null @@ -1,304 +0,0 @@ -/* - * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. - * - * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ - * - * This file contains Original Code and/or Modifications of Original Code - * as defined in and that are subject to the Apple Public Source License - * Version 2.0 (the 'License'). You may not use this file except in - * compliance with the License. The rights granted to you under the License - * may not be used to create, or enable the creation or redistribution of, - * unlawful or unlicensed copies of an Apple operating system, or to - * circumvent, violate, or enable the circumvention or violation of, any - * terms of an Apple operating system software license agreement. - * - * Please obtain a copy of the License at - * http://www.opensource.apple.com/apsl/ and read it before using this file. - * - * The Original Code and all software distributed under the License are - * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER - * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, - * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. - * Please see the License for the specific language governing rights and - * limitations under the License. - * - * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ - */ -/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ -/* - * Copyright (c) 1992, 1993 - * The Regents of the University of California. All rights reserved. - * - * This code is derived from software donated to Berkeley by - * Jan-Simon Pendry. - * - * 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. - * - * @(#)null_subr.c 8.7 (Berkeley) 5/14/95 - * - * null_subr.c 8.4 (Berkeley) 1/21/94 - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define LOG2_SIZEVNODE 7 /* log2(sizeof struct vnode) */ -#define NNULLNODECACHE 16 - -/* - * Null layer cache: - * Each cache entry holds a reference to the lower vnode - * along with a pointer to the alias vnode. When an - * entry is added the lower vnode is vnode_get'd. When the - * alias is removed the lower vnode is vnode_put'd. - */ - -#define NULL_NHASH(vp) \ - (&null_node_hashtbl[(((uintptr_t)vp)>>LOG2_SIZEVNODE) & null_node_hash]) -LIST_HEAD(null_node_hashhead, null_node) *null_node_hashtbl; -u_long null_node_hash; - -/* - * Initialise cache headers - */ -nullfs_init() -{ - -#ifdef NULLFS_DIAGNOSTIC - printf("nullfs_init\n"); /* printed during system boot */ -#endif - null_node_hashtbl = hashinit(NNULLNODECACHE, M_CACHE, &null_node_hash); -} - -/* - * Return a vnode_get'ed alias for lower vnode if already exists, else 0. - */ -static struct vnode * -null_node_find(mp, lowervp) - struct mount *mp; - struct vnode *lowervp; -{ - struct proc *p = curproc; /* XXX */ - struct null_node_hashhead *hd; - struct null_node *a; - struct vnode *vp; - - /* - * Find hash base, and then search the (two-way) linked - * list looking for a null_node structure which is referencing - * the lower vnode. If found, the increment the null_node - * reference count (but NOT the lower vnode's vnode_get counter). - */ - hd = NULL_NHASH(lowervp); -loop: - for (a = hd->lh_first; a != 0; a = a->null_hash.le_next) { - if (a->null_lowervp == lowervp && NULLTOV(a)->v_mount == mp) { - vp = NULLTOV(a); - - if (vnode_get(vp)) { - printf ("null_node_find: vget failed.\n"); - goto loop; - }; - return (vp); - } - } - - return NULL; -} - - -/* - * Make a new null_node node. - * Vp is the alias vnode, lofsvp is the lower vnode. - * Maintain a reference to (lowervp). - */ -static int -null_node_alloc(mp, lowervp, vpp) - struct mount *mp; - struct vnode *lowervp; - struct vnode **vpp; -{ - struct null_node_hashhead *hd; - struct null_node *xp; - struct vnode *othervp, *vp; - int error; - - MALLOC(xp, struct null_node *, sizeof(struct null_node), M_TEMP, M_WAITOK); - if (error = getnewvnode(VT_NULL, mp, null_vnodeop_p, vpp)) { - FREE(xp, M_TEMP); - return (error); - } - vp = *vpp; - - vp->v_type = lowervp->v_type; - xp->null_vnode = vp; - vp->v_data = xp; - xp->null_lowervp = lowervp; - /* - * Before we insert our new node onto the hash chains, - * check to see if someone else has beaten us to it. - */ - if (othervp = null_node_find(lowervp)) { - FREE(xp, M_TEMP); - vp->v_type = VBAD; /* node is discarded */ - vp->v_usecount = 0; /* XXX */ - vp->v_data = 0; /* prevent access to freed data */ - *vpp = othervp; - return 0; - }; - if (vp->v_type == VREG) - ubc_info_init(vp); - vnode_get(lowervp); /* Extra vnode_get will be vnode_put'd in null_node_create */ - hd = NULL_NHASH(lowervp); - LIST_INSERT_HEAD(hd, xp, null_hash); - return 0; -} - - -/* - * Try to find an existing null_node vnode refering - * to it, otherwise make a new null_node vnode which - * contains a reference to the lower vnode. - */ -int -null_node_create(mp, lowervp, newvpp) - struct mount *mp; - struct vnode *lowervp; - struct vnode **newvpp; -{ - struct vnode *aliasvp; - - if (aliasvp = null_node_find(mp, lowervp)) { - /* - * null_node_find has taken another reference - * to the alias vnode. - */ -#ifdef NULLFS_DIAGNOSTIC - vprint("null_node_create: exists", NULLTOV(ap)); -#endif - /* vnode_get(aliasvp); --- done in null_node_find */ - } else { - int error; - - /* - * Get new vnode. - */ -#ifdef NULLFS_DIAGNOSTIC - printf("null_node_create: create new alias vnode\n"); -#endif - - /* - * Make new vnode reference the null_node. - */ - if (error = null_node_alloc(mp, lowervp, &aliasvp)) - return error; - - /* - * aliasvp is already vnode_get'd by getnewvnode() - */ - } - - vnode_put(lowervp); - -#if DIAGNOSTIC - if (lowervp->v_usecount < 1) { - /* Should never happen... */ - vprint ("null_node_create: alias ", aliasvp); - vprint ("null_node_create: lower ", lowervp); - panic ("null_node_create: lower has 0 usecount."); - }; -#endif - -#ifdef NULLFS_DIAGNOSTIC - vprint("null_node_create: alias", aliasvp); - vprint("null_node_create: lower", lowervp); -#endif - - *newvpp = aliasvp; - return (0); -} -#ifdef NULLFS_DIAGNOSTIC -struct vnode * -null_checkvp(vp, fil, lno) - struct vnode *vp; - char *fil; - int lno; -{ - struct null_node *a = VTONULL(vp); -#ifdef notyet - /* - * Can't do this check because vnop_reclaim runs - * with a funny vop vector. - */ - if (vp->v_op != null_vnodeop_p) { - printf ("null_checkvp: on non-null-node\n"); - while (null_checkvp_barrier) /*WAIT*/ ; - panic("null_checkvp"); - }; -#endif - if (a->null_lowervp == NULL) { - /* Should never happen */ - int i; uint32_t *p; - printf("vp = %x, ZERO ptr\n", vp); - for (p = (uint32_t *) a, i = 0; i < 8; i++) - printf(" %x", p[i]); - printf("\n"); - /* wait for debugger */ - while (null_checkvp_barrier) /*WAIT*/ ; - panic("null_checkvp"); - } - if (a->null_lowervp->v_usecount < 1) { - int i; uint32_t *p; - printf("vp = %x, unref'ed lowervp\n", vp); - for (p = (uint32_t *) a, i = 0; i < 8; i++) - printf(" %x", p[i]); - printf("\n"); - /* wait for debugger */ - while (null_checkvp_barrier) /*WAIT*/ ; - panic ("null with unref'ed lowervp"); - }; -#ifdef notyet - printf("null %x/%d -> %x/%d [%s, %d]\n", - NULLTOV(a), NULLTOV(a)->v_usecount, - a->null_lowervp, a->null_lowervp->v_usecount, - fil, lno); -#endif - return a->null_lowervp; -} -#endif