NetBSD/sys/miscfs/umapfs/umap_vfsops.c

317 lines
8.0 KiB
C

/* $NetBSD: umap_vfsops.c,v 1.33 2001/11/15 09:48:23 lukem 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
* the UCLA Ficus project.
*
* 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: @(#)null_vfsops.c 1.5 (Berkeley) 7/10/92
* @(#)umap_vfsops.c 8.8 (Berkeley) 5/14/95
*/
/*
* Umap Layer
* (See mount_umap(8) for a description of this layer.)
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.33 2001/11/15 09:48:23 lukem Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/time.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/namei.h>
#include <sys/malloc.h>
#include <miscfs/umapfs/umap.h>
#include <miscfs/genfs/layer_extern.h>
int umapfs_mount __P((struct mount *, const char *, void *,
struct nameidata *, struct proc *));
int umapfs_unmount __P((struct mount *, int, struct proc *));
/*
* Mount umap layer
*/
int
umapfs_mount(mp, path, data, ndp, p)
struct mount *mp;
const char *path;
void *data;
struct nameidata *ndp;
struct proc *p;
{
struct umap_args args;
struct vnode *lowerrootvp, *vp;
struct umap_mount *amp;
size_t size;
int error;
#ifdef UMAPFS_DIAGNOSTIC
int i;
#endif
/* only for root */
if ((error = suser(p->p_ucred, &p->p_acflag)) != 0)
return error;
#ifdef UMAPFS_DIAGNOSTIC
printf("umapfs_mount(mp = %p)\n", mp);
#endif
/*
* Get argument
*/
error = copyin(data, (caddr_t)&args, sizeof(struct umap_args));
if (error)
return (error);
/*
* Update only does export updating.
*/
if (mp->mnt_flag & MNT_UPDATE) {
amp = MOUNTTOUMAPMOUNT(mp);
if (args.umap_target == 0)
return (vfs_export(mp, &amp->umapm_export,
&args.umap_export));
else
return (EOPNOTSUPP);
}
/*
* Find lower node
*/
NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF,
UIO_USERSPACE, args.umap_target, p);
if ((error = namei(ndp)) != 0)
return (error);
/*
* Sanity check on lower vnode
*/
lowerrootvp = ndp->ni_vp;
#ifdef UMAPFS_DIAGNOSTIC
printf("vp = %p, check for VDIR...\n", lowerrootvp);
#endif
if (lowerrootvp->v_type != VDIR) {
vput(lowerrootvp);
return (EINVAL);
}
#ifdef UMAPFS_DIAGNOSTIC
printf("mp = %p\n", mp);
#endif
amp = (struct umap_mount *) malloc(sizeof(struct umap_mount),
M_UFSMNT, M_WAITOK); /* XXX */
memset((caddr_t)amp, 0, sizeof(struct umap_mount));
mp->mnt_data = (qaddr_t) amp;
amp->umapm_vfs = lowerrootvp->v_mount;
if (amp->umapm_vfs->mnt_flag & MNT_LOCAL)
mp->mnt_flag |= MNT_LOCAL;
/*
* Now copy in the number of entries and maps for umap mapping.
*/
if (args.nentries > MAPFILEENTRIES || args.gnentries > GMAPFILEENTRIES) {
vput(lowerrootvp);
return (error);
}
amp->info_nentries = args.nentries;
amp->info_gnentries = args.gnentries;
error = copyin(args.mapdata, (caddr_t)amp->info_mapdata,
2*sizeof(u_long)*args.nentries);
if (error) {
vput(lowerrootvp);
return (error);
}
#ifdef UMAPFS_DIAGNOSTIC
printf("umap_mount:nentries %d\n",args.nentries);
for (i = 0; i < args.nentries; i++)
printf(" %ld maps to %ld\n", amp->info_mapdata[i][0],
amp->info_mapdata[i][1]);
#endif
error = copyin(args.gmapdata, (caddr_t)amp->info_gmapdata,
2*sizeof(u_long)*args.gnentries);
if (error) {
vput(lowerrootvp);
return (error);
}
#ifdef UMAPFS_DIAGNOSTIC
printf("umap_mount:gnentries %d\n",args.gnentries);
for (i = 0; i < args.gnentries; i++)
printf("\tgroup %ld maps to %ld\n",
amp->info_gmapdata[i][0],
amp->info_gmapdata[i][1]);
#endif
/*
* Make sure the mount point's sufficiently initialized
* that the node create call will work.
*/
vfs_getnewfsid(mp);
amp->umapm_size = sizeof(struct umap_node);
amp->umapm_tag = VT_UMAP;
amp->umapm_bypass = umap_bypass;
amp->umapm_alloc = layer_node_alloc; /* the default alloc is fine */
amp->umapm_vnodeop_p = umap_vnodeop_p;
simple_lock_init(&amp->umapm_hashlock);
amp->umapm_node_hashtbl = hashinit(NUMAPNODECACHE, HASH_LIST, M_CACHE,
M_WAITOK, &amp->umapm_node_hash);
/*
* fix up umap node for root vnode.
*/
error = layer_node_create(mp, lowerrootvp, &vp);
/*
* Make sure the node alias worked
*/
if (error) {
vput(lowerrootvp);
free(amp, M_UFSMNT); /* XXX */
return (error);
}
/*
* Unlock the node (either the lower or the alias)
*/
VOP_UNLOCK(vp, 0);
/*
* Keep a held reference to the root vnode.
* It is vrele'd in umapfs_unmount.
*/
vp->v_flag |= VROOT;
amp->umapm_rootvp = vp;
(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size);
(void) copyinstr(args.umap_target, mp->mnt_stat.f_mntfromname,
MNAMELEN - 1, &size);
memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size);
#ifdef UMAPFS_DIAGNOSTIC
printf("umapfs_mount: lower %s, alias at %s\n",
mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
#endif
return (0);
}
/*
* Free reference to umap layer
*/
int
umapfs_unmount(mp, mntflags, p)
struct mount *mp;
int mntflags;
struct proc *p;
{
struct vnode *rootvp = MOUNTTOUMAPMOUNT(mp)->umapm_rootvp;
int error;
int flags = 0;
#ifdef UMAPFS_DIAGNOSTIC
printf("umapfs_unmount(mp = %p)\n", mp);
#endif
if (mntflags & MNT_FORCE)
flags |= FORCECLOSE;
/*
* Clear out buffer cache. I don't think we
* ever get anything cached at this level at the
* moment, but who knows...
*/
#ifdef notyet
mntflushbuf(mp, 0);
if (mntinvalbuf(mp, 1))
return (EBUSY);
#endif
if (rootvp->v_usecount > 1)
return (EBUSY);
if ((error = vflush(mp, rootvp, flags)) != 0)
return (error);
#ifdef UMAPFS_DIAGNOSTIC
vprint("alias root of lower", rootvp);
#endif
/*
* Release reference on underlying root vnode
*/
vrele(rootvp);
/*
* And blow it away for future re-use
*/
vgone(rootvp);
/*
* Finally, throw away the umap_mount structure
*/
free(mp->mnt_data, M_UFSMNT); /* XXX */
mp->mnt_data = 0;
return (0);
}
extern const struct vnodeopv_desc umapfs_vnodeop_opv_desc;
const struct vnodeopv_desc * const umapfs_vnodeopv_descs[] = {
&umapfs_vnodeop_opv_desc,
NULL,
};
struct vfsops umapfs_vfsops = {
MOUNT_UMAP,
umapfs_mount,
layerfs_start,
umapfs_unmount,
layerfs_root,
layerfs_quotactl,
layerfs_statfs,
layerfs_sync,
layerfs_vget,
layerfs_fhtovp,
layerfs_vptofh,
layerfs_init,
NULL,
layerfs_done,
layerfs_sysctl,
NULL, /* vfs_mountroot */
layerfs_checkexp,
umapfs_vnodeopv_descs,
};