455 lines
11 KiB
C
455 lines
11 KiB
C
/* $NetBSD: umap_subr.c,v 1.13 1998/03/01 02:21:51 fvdl Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1992, 1993, 1995
|
|
* 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 8.9 (Berkeley) 5/14/95
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/proc.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 <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;
|
|
|
|
static u_long umap_findid __P((u_long, u_long [][2], int));
|
|
static struct vnode *umap_node_find __P((struct mount *, struct vnode *));
|
|
static int umap_node_alloc __P((struct mount *, struct vnode *,
|
|
struct vnode **));
|
|
|
|
/*
|
|
* Initialise cache headers
|
|
*/
|
|
void
|
|
umapfs_init()
|
|
{
|
|
|
|
#ifdef UMAPFS_DIAGNOSTIC
|
|
printf("umapfs_init\n"); /* printed during system boot */
|
|
#endif
|
|
umap_node_hashtbl = hashinit(NUMAPNODECACHE, M_CACHE, M_WAITOK, &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 = %p, target = %p)\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)) {
|
|
#ifdef UMAPFS_DIAGNOSTIC
|
|
printf ("umap_node_find: vget failed.\n");
|
|
#endif
|
|
goto loop;
|
|
}
|
|
return (vp);
|
|
}
|
|
}
|
|
|
|
#ifdef UMAPFS_DIAGNOSTIC
|
|
printf("umap_node_find(%p, %p): 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;
|
|
struct proc *p = curproc; /* XXX */
|
|
int error;
|
|
extern int (**dead_vnodeop_p) __P((void *));
|
|
|
|
if ((error = getnewvnode(VT_UMAP, mp, umap_vnodeop_p, &vp)) != 0)
|
|
return (error);
|
|
vp->v_type = lowervp->v_type;
|
|
|
|
MALLOC(xp, struct umap_node *, sizeof(struct umap_node), M_TEMP,
|
|
M_WAITOK);
|
|
if (vp->v_type == VBLK || vp->v_type == VCHR) {
|
|
MALLOC(vp->v_specinfo, struct specinfo *,
|
|
sizeof(struct specinfo), M_VNODE, M_WAITOK);
|
|
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.
|
|
* (We could have slept in MALLOC.)
|
|
*/
|
|
if ((nvp = umap_node_find(mp, lowervp)) != NULL) {
|
|
*vpp = nvp;
|
|
|
|
/* free the substructures we've allocated. */
|
|
FREE(xp, M_TEMP);
|
|
if (vp->v_type == VBLK || vp->v_type == VCHR)
|
|
FREE(vp->v_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:
|
|
simple_lock(&spechash_slock);
|
|
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.
|
|
*/
|
|
simple_lock(&cvp->v_interlock);
|
|
if (cvp->v_usecount == 0) {
|
|
simple_unlock(&spechash_slock);
|
|
vgonel(cvp, p);
|
|
goto loop;
|
|
}
|
|
if (vget(cvp, LK_EXCLUSIVE | LK_INTERLOCK)) {
|
|
simple_unlock(&spechash_slock);
|
|
goto loop;
|
|
}
|
|
break;
|
|
}
|
|
|
|
vp->v_hashchain = cvpp;
|
|
vp->v_specnext = *cvpp;
|
|
vp->v_specflags = 0;
|
|
*cvpp = vp;
|
|
#ifdef DIAGNOSTIC
|
|
if (cvp == NULLVP)
|
|
panic("umap_node_alloc: no alias for device");
|
|
#endif
|
|
vp->v_flag |= VALIASED;
|
|
cvp->v_flag |= VALIASED;
|
|
simple_unlock(&spechash_slock);
|
|
vrele(cvp);
|
|
}
|
|
/* XXX end of transmogrified checkalias() */
|
|
|
|
*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)) != NULL) {
|
|
/*
|
|
* Take another reference to the alias vnode
|
|
*/
|
|
#ifdef UMAPFS_DIAGNOSTIC
|
|
vprint("umap_node_create: exists", aliasvp);
|
|
#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)) != 0)
|
|
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 = %p, ZERO ptr\n", vp);
|
|
for (p = (u_long *) a, i = 0; i < 8; i++)
|
|
printf(" %lx", 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 = %p, unref'ed lowervp\n", vp);
|
|
for (p = (u_long *) a, i = 0; i < 8; i++)
|
|
printf(" %lx", p[i]);
|
|
printf("\n");
|
|
/* wait for debugger */
|
|
while (umap_checkvp_barrier) /*WAIT*/ ;
|
|
panic ("umap with unref'ed lowervp");
|
|
}
|
|
#if 0
|
|
printf("umap %p/%d -> %p/%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;
|
|
gid_t gid;
|
|
u_long (*usermap)[2], (*groupmap)[2];
|
|
|
|
if (credp == NOCRED)
|
|
return;
|
|
|
|
unentries = MOUNTTOUMAPMOUNT(v_mount)->info_nentries;
|
|
usermap = MOUNTTOUMAPMOUNT(v_mount)->info_mapdata;
|
|
gnentries = MOUNTTOUMAPMOUNT(v_mount)->info_gnentries;
|
|
groupmap = MOUNTTOUMAPMOUNT(v_mount)->info_gmapdata;
|
|
|
|
/* 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;
|
|
|
|
#if 1
|
|
/* cr_gid is the same as cr_groups[0] in 4BSD, but not in NetBSD */
|
|
|
|
/* 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;
|
|
}
|
|
}
|