+++ /dev/null
-/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- *
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- *
- * This 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 OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- *
- * @APPLE_LICENSE_HEADER_END@
- */
-/* $NetBSD: umap_subr.c,v 1.4 1994/09/20 06:43:02 cgd Exp $ */
-
-/*
- * 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.
- *
- * from: Id: lofs_subr.c, v 1.11 1992/05/30 10:05:43 jsp Exp
- * @(#)umap_subr.c 8.6 (Berkeley) 1/26/94
- */
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/vnode.h>
-#include <sys/mount.h>
-#include <sys/namei.h>
-#include <sys/malloc.h>
-#include <sys/ubc.h>
-#include <miscfs/specfs/specdev.h>
-#include <miscfs/umapfs/umap.h>
-
-#define LOG2_SIZEVNODE 7 /* log2(sizeof struct vnode) */
-#define NUMAPNODECACHE 16
-
-/*
- * Null layer cache:
- * Each cache entry holds a reference to the target vnode
- * along with a pointer to the alias vnode. When an
- * entry is added the target vnode is VREF'd. When the
- * alias is removed the target vnode is vrele'd.
- */
-
-#define UMAP_NHASH(vp) \
- (&umap_node_hashtbl[(((u_long)vp)>>LOG2_SIZEVNODE) & umap_node_hash])
-LIST_HEAD(umap_node_hashhead, umap_node) *umap_node_hashtbl;
-u_long umap_node_hash;
-
-/*
- * Initialise cache headers
- */
-umapfs_init()
-{
-
-#ifdef UMAPFS_DIAGNOSTIC
- printf("umapfs_init\n"); /* printed during system boot */
-#endif
- umap_node_hashtbl = hashinit(NUMAPNODECACHE, M_CACHE, &umap_node_hash);
-}
-
-/*
- * umap_findid is called by various routines in umap_vnodeops.c to
- * find a user or group id in a map.
- */
-static u_long
-umap_findid(id, map, nentries)
- u_long id;
- u_long map[][2];
- int nentries;
-{
- int i;
-
- /* Find uid entry in map */
- i = 0;
- while ((i<nentries) && ((map[i][0]) != id))
- i++;
-
- if (i < nentries)
- return (map[i][1]);
- else
- return (-1);
-
-}
-
-/*
- * umap_reverse_findid is called by umap_getattr() in umap_vnodeops.c to
- * find a user or group id in a map, in reverse.
- */
-u_long
-umap_reverse_findid(id, map, nentries)
- u_long id;
- u_long map[][2];
- int nentries;
-{
- int i;
-
- /* Find uid entry in map */
- i = 0;
- while ((i<nentries) && ((map[i][1]) != id))
- i++;
-
- if (i < nentries)
- return (map[i][0]);
- else
- return (-1);
-
-}
-
-/*
- * Return alias for target vnode if already exists, else 0.
- */
-static struct vnode *
-umap_node_find(mp, targetvp)
- struct mount *mp;
- struct vnode *targetvp;
-{
- struct umap_node_hashhead *hd;
- struct umap_node *a;
- struct vnode *vp;
-
-#ifdef UMAPFS_DIAGNOSTIC
- printf("umap_node_find(mp = %x, target = %x)\n", mp, targetvp);
-#endif
-
- /*
- * Find hash base, and then search the (two-way) linked
- * list looking for a umap_node structure which is referencing
- * the target vnode. If found, the increment the umap_node
- * reference count (but NOT the target vnode's VREF counter).
- */
- hd = UMAP_NHASH(targetvp);
-loop:
- for (a = hd->lh_first; a != 0; a = a->umap_hash.le_next) {
- if (a->umap_lowervp == targetvp &&
- a->umap_vnode->v_mount == mp) {
- vp = UMAPTOV(a);
- /*
- * We need vget for the VXLOCK
- * stuff, but we don't want to lock
- * the lower node.
- */
- if (vget(vp, 0, current_proc())) {
-#ifdef UMAPFS_DIAGNOSTIC
- printf ("umap_node_find: vget failed.\n");
-#endif
- goto loop;
- }
- return (vp);
- }
- }
-
-#ifdef UMAPFS_DIAGNOSTIC
- printf("umap_node_find(%x, %x): NOT found\n", mp, targetvp);
-#endif
-
- return (0);
-}
-
-/*
- * Make a new umap_node node.
- * Vp is the alias vnode, lowervp is the target vnode.
- * Maintain a reference to lowervp.
- */
-static int
-umap_node_alloc(mp, lowervp, vpp)
- struct mount *mp;
- struct vnode *lowervp;
- struct vnode **vpp;
-{
- struct umap_node_hashhead *hd;
- struct umap_node *xp;
- struct vnode *vp, *nvp;
- int error;
- extern int (**dead_vnodeop_p)(void *);
- struct specinfo *sp = (struct specinfo *)0;
-
- if (lowervp->v_type == VBLK || lowervp->v_type == VCHR)
- MALLOC_ZONE(sp, struct specinfo *, sizeof(struct specinfo),
- M_VNODE, M_WAITOK);
-
- MALLOC(xp, struct umap_node *, sizeof(struct umap_node), M_TEMP,
- M_WAITOK);
- if (error = getnewvnode(VT_UMAP, mp, umap_vnodeop_p, &vp)) {
- FREE(xp, M_TEMP);
- if (sp)
- FREE_ZONE(sp, sizeof (struct specinfo), M_VNODE);
- return (error);
- }
- vp->v_type = lowervp->v_type;
-
- if (vp->v_type == VBLK || vp->v_type == VCHR) {
- vp->v_specinfo = sp;
- vp->v_rdev = lowervp->v_rdev;
- }
-
- vp->v_data = xp;
- xp->umap_vnode = vp;
- xp->umap_lowervp = lowervp;
- /*
- * Before we insert our new node onto the hash chains,
- * check to see if someone else has beaten us to it.
- */
- if (nvp = umap_node_find(lowervp)) {
- *vpp = nvp;
-
- /* free the substructures we've allocated. */
- FREE(xp, M_TEMP);
- if (sp) {
- vp->v_specinfo = (struct specinfo *)0;
- FREE_ZONE(sp, sizeof (struct specinfo), M_VNODE);
- }
-
- vp->v_type = VBAD; /* node is discarded */
- vp->v_op = dead_vnodeop_p; /* so ops will still work */
- vrele(vp); /* get rid of it. */
- return (0);
- }
-
- /*
- * XXX if it's a device node, it needs to be checkalias()ed.
- * however, for locking reasons, that's just not possible.
- * so we have to do most of the dirty work inline. Note that
- * this is a limited case; we know that there's going to be
- * an alias, and we know that that alias will be a "real"
- * device node, i.e. not tagged VT_NON.
- */
- if (vp->v_type == VBLK || vp->v_type == VCHR) {
- struct vnode *cvp, **cvpp;
-
- cvpp = &speclisth[SPECHASH(vp->v_rdev)];
-loop:
- for (cvp = *cvpp; cvp; cvp = cvp->v_specnext) {
- if (vp->v_rdev != cvp->v_rdev ||
- vp->v_type != cvp->v_type)
- continue;
-
- /*
- * Alias, but not in use, so flush it out.
- */
- if (cvp->v_usecount == 0) {
- vgone(cvp);
- goto loop;
- }
- if (vget(cvp, 0, current_proc())) /* can't lock; will die! */
- goto loop;
- break;
- }
-
- vp->v_hashchain = cvpp;
- vp->v_specnext = *cvpp;
- vp->v_specflags = 0;
- *cvpp = vp;
-#if DIAGNOSTIC
- if (cvp == NULLVP)
- panic("umap_node_alloc: no alias for device");
-#endif
- vp->v_flag |= VALIASED;
- cvp->v_flag |= VALIASED;
- vrele(cvp);
- }
- /* XXX end of transmogrified checkalias() */
-
- if (vp->v_type == VREG)
- ubc_info_init(vp);
-
- *vpp = vp;
- VREF(lowervp); /* Extra VREF will be vrele'd in umap_node_create */
- hd = UMAP_NHASH(lowervp);
- LIST_INSERT_HEAD(hd, xp, umap_hash);
- return (0);
-}
-
-
-/*
- * Try to find an existing umap_node vnode refering
- * to it, otherwise make a new umap_node vnode which
- * contains a reference to the target vnode.
- */
-int
-umap_node_create(mp, targetvp, newvpp)
- struct mount *mp;
- struct vnode *targetvp;
- struct vnode **newvpp;
-{
- struct vnode *aliasvp;
-
- if (aliasvp = umap_node_find(mp, targetvp)) {
- /*
- * Take another reference to the alias vnode
- */
-#ifdef UMAPFS_DIAGNOSTIC
- vprint("umap_node_create: exists", ap->umap_vnode);
-#endif
- /* VREF(aliasvp); */
- } else {
- int error;
-
- /*
- * Get new vnode.
- */
-#ifdef UMAPFS_DIAGNOSTIC
- printf("umap_node_create: create new alias vnode\n");
-#endif
- /*
- * Make new vnode reference the umap_node.
- */
- if (error = umap_node_alloc(mp, targetvp, &aliasvp))
- return (error);
-
- /*
- * aliasvp is already VREF'd by getnewvnode()
- */
- }
-
- vrele(targetvp);
-
-#ifdef UMAPFS_DIAGNOSTIC
- vprint("umap_node_create: alias", aliasvp);
- vprint("umap_node_create: target", targetvp);
-#endif
-
- *newvpp = aliasvp;
- return (0);
-}
-
-#ifdef UMAPFS_DIAGNOSTIC
-int umap_checkvp_barrier = 1;
-struct vnode *
-umap_checkvp(vp, fil, lno)
- struct vnode *vp;
- char *fil;
- int lno;
-{
- struct umap_node *a = VTOUMAP(vp);
-#if 0
- /*
- * Can't do this check because vop_reclaim runs
- * with funny vop vector.
- */
- if (vp->v_op != umap_vnodeop_p) {
- printf ("umap_checkvp: on non-umap-node\n");
- while (umap_checkvp_barrier) /*WAIT*/ ;
- panic("umap_checkvp");
- }
-#endif
- if (a->umap_lowervp == NULL) {
- /* Should never happen */
- int i; u_long *p;
- printf("vp = %x, ZERO ptr\n", vp);
- for (p = (u_long *) a, i = 0; i < 8; i++)
- printf(" %x", p[i]);
- printf("\n");
- /* wait for debugger */
- while (umap_checkvp_barrier) /*WAIT*/ ;
- panic("umap_checkvp");
- }
- if (a->umap_lowervp->v_usecount < 1) {
- int i; u_long *p;
- printf("vp = %x, unref'ed lowervp\n", vp);
- for (p = (u_long *) a, i = 0; i < 8; i++)
- printf(" %x", p[i]);
- printf("\n");
- /* wait for debugger */
- while (umap_checkvp_barrier) /*WAIT*/ ;
- panic ("umap with unref'ed lowervp");
- }
-#if 0
- printf("umap %x/%d -> %x/%d [%s, %d]\n",
- a->umap_vnode, a->umap_vnode->v_usecount,
- a->umap_lowervp, a->umap_lowervp->v_usecount,
- fil, lno);
-#endif
- return (a->umap_lowervp);
-}
-#endif
-
-/* umap_mapids maps all of the ids in a credential, both user and group. */
-
-void
-umap_mapids(v_mount, credp)
- struct mount *v_mount;
- struct ucred *credp;
-{
- int i, unentries, gnentries;
- uid_t uid, *usermap;
- gid_t gid, *groupmap;
-
- unentries = MOUNTTOUMAPMOUNT(v_mount)->info_nentries;
- usermap = &(MOUNTTOUMAPMOUNT(v_mount)->info_mapdata[0][0]);
- gnentries = MOUNTTOUMAPMOUNT(v_mount)->info_gnentries;
- groupmap = &(MOUNTTOUMAPMOUNT(v_mount)->info_gmapdata[0][0]);
-
- /* Find uid entry in map */
-
- uid = (uid_t) umap_findid(credp->cr_uid, usermap, unentries);
-
- if (uid != -1)
- credp->cr_uid = uid;
- else
- credp->cr_uid = (uid_t) NOBODY;
-
-#ifdef notdef
- /* cr_gid is the same as cr_groups[0] in 4BSD */
-
- /* Find gid entry in map */
-
- gid = (gid_t) umap_findid(credp->cr_gid, groupmap, gnentries);
-
- if (gid != -1)
- credp->cr_gid = gid;
- else
- credp->cr_gid = NULLGROUP;
-#endif
-
- /* Now we must map each of the set of groups in the cr_groups
- structure. */
-
- i = 0;
- while (credp->cr_groups[i] != 0) {
- gid = (gid_t) umap_findid(credp->cr_groups[i],
- groupmap, gnentries);
-
- if (gid != -1)
- credp->cr_groups[i++] = gid;
- else
- credp->cr_groups[i++] = NULLGROUP;
- }
-}
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