+++ /dev/null
-/*
- * Copyright (c) 2000-2006 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) 1994, 1995 The Regents of the University of California.
- * Copyright (c) 1994, 1995 Jan-Simon Pendry.
- * 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.
- *
- * @(#)union_vfsops.c 8.20 (Berkeley) 5/20/95
- */
-
-/*
- * Union Layer
- */
-
-#include <sys/param.h>
-#include <sys/systm.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/proc_internal.h>
-#include <sys/kauth.h>
-#include <sys/vnode_internal.h>
-#include <sys/mount_internal.h>
-#include <sys/namei.h>
-#include <sys/malloc.h>
-#include <sys/filedesc.h>
-#include <sys/queue.h>
-#include <miscfs/union/union.h>
-
-static int union_itercallback(vnode_t, void *);
-static int union_root(mount_t, vnode_t *, vfs_context_t);
-
-/*
- * Mount union filesystem
- */
-static int
-union_mount(mount_t mp, __unused vnode_t devvp, user_addr_t data, vfs_context_t context)
-{
- proc_t p = vfs_context_proc(context);
- int error = 0;
- struct user_union_args args;
- struct vnode *lowerrootvp = NULLVP;
- struct vnode *upperrootvp = NULLVP;
- struct union_mount *um = NULL;
- kauth_cred_t cred = NOCRED;
- const char *cp = NULL;
- char *vcp;
- int len;
- u_int size;
- struct nameidata nd;
-
-#ifdef UNION_DIAGNOSTIC
- printf("union_mount(mp = %x)\n", mp);
-#endif
-
- /*
- * Update is a no-op
- */
- if (mp->mnt_flag & MNT_UPDATE) {
- /*
- * Need to provide.
- * 1. a way to convert between rdonly and rdwr mounts.
- * 2. support for nfs exports.
- */
- error = ENOTSUP;
- goto bad;
- }
-
- /*
- * Get argument
- */
- if (vfs_context_is64bit(context)) {
- error = copyin(data, (caddr_t)&args, sizeof(args));
- }
- else {
- struct union_args temp;
- error = copyin(data, (caddr_t)&temp, sizeof (temp));
- args.target = CAST_USER_ADDR_T(temp.target);
- args.mntflags = temp.mntflags;
- }
- if (error)
- goto bad;
-
- lowerrootvp = mp->mnt_vnodecovered;
- vnode_get(lowerrootvp);
-
- /*
- * Find upper node.
- */
- NDINIT(&nd, LOOKUP, FOLLOW|WANTPARENT,
- (IS_64BIT_PROCESS(p) ? UIO_USERSPACE64 : UIO_USERSPACE32),
- args.target, context);
-
- if ((error = namei(&nd)))
- goto bad;
-
- nameidone(&nd);
- upperrootvp = nd.ni_vp;
- vnode_put(nd.ni_dvp);
- nd.ni_dvp = NULL;
-
- if (upperrootvp->v_type != VDIR) {
- error = EINVAL;
- goto bad;
- }
-
- MALLOC(um, struct union_mount *, sizeof(struct union_mount),
- M_UFSMNT, M_WAITOK);
-
- /*
- * Keep a held reference to the target vnodes.
- * They are vnode_put'd in union_unmount.
- *
- * Depending on the _BELOW flag, the filesystems are
- * viewed in a different order. In effect, this is the
- * same as providing a mount under option to the mount syscall.
- */
-
- um->um_op = args.mntflags & UNMNT_OPMASK;
- switch (um->um_op) {
- case UNMNT_ABOVE:
- um->um_lowervp = lowerrootvp;
- um->um_uppervp = upperrootvp;
- break;
-
- case UNMNT_BELOW:
- um->um_lowervp = upperrootvp;
- um->um_uppervp = lowerrootvp;
- break;
-
- case UNMNT_REPLACE:
- vnode_put(lowerrootvp);
- lowerrootvp = NULLVP;
- um->um_uppervp = upperrootvp;
- um->um_lowervp = lowerrootvp;
- break;
-
-#ifdef FAULTFS
- case UNMNT_FAULTIN:
- um->um_lowervp = upperrootvp;
- um->um_uppervp = lowerrootvp;
- break;
-#endif
-
- default:
- error = EINVAL;
- goto bad;
- }
-
- if (um->um_lowervp != NULLVP)
- um->um_lowervid = vnode_vid(um->um_lowervp);
- if (um->um_uppervp != NULLVP)
- um->um_uppervid = vnode_vid(um->um_uppervp);
- /*
- * Unless the mount is readonly, ensure that the top layer
- * supports whiteout operations
- */
-#ifdef FAULTFS
- if ((um->um_op != UNMNT_FAULTIN) && (mp->mnt_flag & MNT_RDONLY) == 0)
-#else
- if ((mp->mnt_flag & MNT_RDONLY) == 0)
-#endif
- {
- error = VNOP_WHITEOUT(um->um_uppervp, (struct componentname *) 0,
- LOOKUP, context);
- if (error)
- goto bad;
- }
-
- um->um_cred = kauth_cred_get_with_ref();
- um->um_cmode = UN_DIRMODE &~ p->p_fd->fd_cmask;
-
- /*
- * Depending on what you think the MNT_LOCAL flag might mean,
- * you may want the && to be || on the conditional below.
- * At the moment it has been defined that the filesystem is
- * only local if it is all local, ie the MNT_LOCAL flag implies
- * that the entire namespace is local. If you think the MNT_LOCAL
- * flag implies that some of the files might be stored locally
- * then you will want to change the conditional.
- */
- if (um->um_op == UNMNT_ABOVE) {
- if (((um->um_lowervp == NULLVP) ||
- (um->um_lowervp->v_mount->mnt_flag & MNT_LOCAL)) &&
- (um->um_uppervp->v_mount->mnt_flag & MNT_LOCAL))
- mp->mnt_flag |= MNT_LOCAL;
- }
-
- /*
- * Copy in the upper layer's RDONLY flag. This is for the benefit
- * of lookup() which explicitly checks the flag, rather than asking
- * the filesystem for it's own opinion. This means, that an update
- * mount of the underlying filesystem to go from rdonly to rdwr
- * will leave the unioned view as read-only.
- */
- mp->mnt_flag |= (um->um_uppervp->v_mount->mnt_flag & MNT_RDONLY);
-
- mp->mnt_data = (qaddr_t) um;
- vfs_getnewfsid(mp);
-
-
- switch (um->um_op) {
- case UNMNT_ABOVE:
- cp = "<above>:";
- break;
- case UNMNT_BELOW:
- cp = "<below>:";
- break;
- case UNMNT_REPLACE:
- cp = "";
- break;
-#ifdef FAULTFS
- case UNMNT_FAULTIN:
- cp = "/FaultingFS/";
- break;
-#endif
- }
- len = strlen(cp);
- bcopy(cp, mp->mnt_vfsstat.f_mntfromname, len);
-
- vcp = mp->mnt_vfsstat.f_mntfromname + len;
- len = MNAMELEN - len;
-
- (void) copyinstr(args.target, vcp, len - 1, (size_t *)&size);
- bzero(vcp + size, len - size);
-
-#ifdef UNION_DIAGNOSTIC
- printf("union_mount: from %s, on %s\n",
- mp->mnt_vfsstat.f_mntfromname, mp->mnt_vfsstat.f_mntonname);
-#endif
- return (0);
-
-bad:
- if (um)
- _FREE(um, M_UFSMNT);
- if (IS_VALID_CRED(cred))
- kauth_cred_unref(&cred);
- if (upperrootvp)
- vnode_put(upperrootvp);
- if (lowerrootvp)
- vnode_put(lowerrootvp);
- return (error);
-}
-
-/*
- * VFS start. Nothing needed here - the start routine
- * on the underlying filesystem(s) will have been called
- * when that filesystem was mounted.
- */
-static int
-union_start(__unused struct mount *mp, __unused int flags, __unused vfs_context_t context)
-{
-
- return (0);
-}
-
-static int
-union_itercallback(__unused vnode_t vp, void *args)
-{
- int num = *(int *)args;
-
- *(int *)args = num + 1;
- return(VNODE_RETURNED);
-}
-
-
-
-/*
- * Free reference to union layer
- */
-static int
-union_unmount(mount_t mp, int mntflags, vfs_context_t context)
-{
- struct union_mount *um = MOUNTTOUNIONMOUNT(mp);
- struct vnode *um_rootvp;
- int error;
- int freeing;
- int flags = 0;
-
-#ifdef UNION_DIAGNOSTIC
- printf("union_unmount(mp = %x)\n", mp);
-#endif
-
- if (mntflags & MNT_FORCE)
- flags |= FORCECLOSE;
-
- if ((error = union_root(mp, &um_rootvp, context)))
- return (error);
-
- /*
- * Keep flushing vnodes from the mount list.
- * This is needed because of the un_pvp held
- * reference to the parent vnode.
- * If more vnodes have been freed on a given pass,
- * the try again. The loop will iterate at most
- * (d) times, where (d) is the maximum tree depth
- * in the filesystem.
- */
- for (freeing = 0; vflush(mp, um_rootvp, flags) != 0;) {
- int n = 0;
-
- vnode_iterate(mp, VNODE_NOLOCK_INTERNAL, union_itercallback, &n);
-
- /* if this is unchanged then stop */
- if (n == freeing)
- break;
-
- /* otherwise try once more time */
- freeing = n;
- }
-
- /* At this point the root vnode should have a single reference */
- if (vnode_isinuse(um_rootvp, 0)) {
- vnode_put(um_rootvp);
- return (EBUSY);
- }
-
-#ifdef UNION_DIAGNOSTIC
- vprint("union root", um_rootvp);
-#endif
- /*
- * Discard references to upper and lower target vnodes.
- */
- if (um->um_lowervp)
- vnode_put(um->um_lowervp);
- vnode_put(um->um_uppervp);
- if (IS_VALID_CRED(um->um_cred)) {
- kauth_cred_unref(&um->um_cred);
- }
- /*
- * Release reference on underlying root vnode
- */
- vnode_put(um_rootvp);
- /*
- * And blow it away for future re-use
- */
- vnode_reclaim(um_rootvp);
- /*
- * Finally, throw away the union_mount structure
- */
- _FREE(mp->mnt_data, M_UFSMNT); /* XXX */
- mp->mnt_data = NULL;
- return (0);
-}
-
-static int
-union_root(mount_t mp, vnode_t *vpp, __unused vfs_context_t context)
-{
- struct union_mount *um = MOUNTTOUNIONMOUNT(mp);
- int error;
-
- /*
- * Return locked reference to root.
- */
- vnode_get(um->um_uppervp);
- if (um->um_lowervp)
- vnode_get(um->um_lowervp);
-
- union_lock();
- error = union_allocvp(vpp, mp,
- (struct vnode *) 0,
- (struct vnode *) 0,
- (struct componentname *) 0,
- um->um_uppervp,
- um->um_lowervp,
- 1);
- union_unlock();
-
- if (error) {
- vnode_put(um->um_uppervp);
- if (um->um_lowervp)
- vnode_put(um->um_lowervp);
- }
-
- return (error);
-}
-
-static int
-union_vfs_getattr(mount_t mp, struct vfs_attr *fsap, vfs_context_t context)
-{
- int error;
- struct union_mount *um = MOUNTTOUNIONMOUNT(mp);
- struct vfs_attr attr;
- uint32_t lbsize = 0;
-
-#ifdef UNION_DIAGNOSTIC
- printf("union_vfs_getattr(mp = %x, lvp = %x, uvp = %x)\n", mp,
- um->um_lowervp,
- um->um_uppervp);
-#endif
-
- /* Get values from lower file system (if any) */
- if (um->um_lowervp) {
- VFSATTR_INIT(&attr);
- VFSATTR_WANTED(&attr, f_bsize);
- VFSATTR_WANTED(&attr, f_blocks);
- VFSATTR_WANTED(&attr, f_bused);
- VFSATTR_WANTED(&attr, f_files);
- error = vfs_getattr(um->um_lowervp->v_mount, &attr, context);
- if (error)
- return (error);
-
- /* now copy across the "interesting" information and fake the rest */
- if (VFSATTR_IS_SUPPORTED(&attr, f_bsize))
- lbsize = attr.f_bsize;
- else
- lbsize = um->um_lowervp->v_mount->mnt_devblocksize;
- fsap->f_blocks = VFSATTR_IS_SUPPORTED(&attr, f_blocks) ? attr.f_blocks : 0;
- fsap->f_bused = VFSATTR_IS_SUPPORTED(&attr, f_bused) ? attr.f_bused : 0;
- fsap->f_files = VFSATTR_IS_SUPPORTED(&attr, f_files) ? attr.f_files : 0;
- } else {
- fsap->f_blocks = 0;
- fsap->f_bused = 0;
- fsap->f_files = 0;
- }
-
- VFSATTR_INIT(&attr);
- VFSATTR_WANTED(&attr, f_bsize);
- VFSATTR_WANTED(&attr, f_blocks);
- VFSATTR_WANTED(&attr, f_bfree);
- VFSATTR_WANTED(&attr, f_bavail);
- VFSATTR_WANTED(&attr, f_files);
- VFSATTR_WANTED(&attr, f_ffree);
- error = vfs_getattr(um->um_uppervp->v_mount, &attr, context);
- if (error)
- return (error);
-
- if (VFSATTR_IS_SUPPORTED(&attr, f_bsize)) {
- fsap->f_bsize = attr.f_bsize;
- VFSATTR_SET_SUPPORTED(fsap, f_bsize);
- }
- if (VFSATTR_IS_SUPPORTED(&attr, f_iosize)) {
- fsap->f_iosize = attr.f_iosize;
- VFSATTR_SET_SUPPORTED(fsap, f_iosize);
- }
-
- /*
- * if the lower and upper blocksizes differ, then frig the
- * block counts so that the sizes reported by df make some
- * kind of sense. none of this makes sense though.
- */
- if (VFSATTR_IS_SUPPORTED(&attr, f_bsize))
- fsap->f_bsize = attr.f_bsize;
- else
- fsap->f_bsize = um->um_uppervp->v_mount->mnt_devblocksize;
- VFSATTR_RETURN(fsap, f_bsize, attr.f_bsize);
- if (fsap->f_bsize != lbsize)
- fsap->f_blocks = fsap->f_blocks * lbsize / attr.f_bsize;
-
- /*
- * The "total" fields count total resources in all layers,
- * the "free" fields count only those resources which are
- * free in the upper layer (since only the upper layer
- * is writeable).
- */
- if (VFSATTR_IS_SUPPORTED(&attr, f_blocks))
- fsap->f_blocks += attr.f_blocks;
- if (VFSATTR_IS_SUPPORTED(&attr, f_bfree))
- fsap->f_bfree = attr.f_bfree;
- if (VFSATTR_IS_SUPPORTED(&attr, f_bavail))
- fsap->f_bavail = attr.f_bavail;
- if (VFSATTR_IS_SUPPORTED(&attr, f_bused))
- fsap->f_bused += attr.f_bused;
- if (VFSATTR_IS_SUPPORTED(&attr, f_files))
- fsap->f_files += attr.f_files;
- if (VFSATTR_IS_SUPPORTED(&attr, f_ffree))
- fsap->f_ffree = attr.f_ffree;
-
- VFSATTR_SET_SUPPORTED(fsap, f_bsize);
- VFSATTR_SET_SUPPORTED(fsap, f_blocks);
- VFSATTR_SET_SUPPORTED(fsap, f_bfree);
- VFSATTR_SET_SUPPORTED(fsap, f_bavail);
- VFSATTR_SET_SUPPORTED(fsap, f_bused);
- VFSATTR_SET_SUPPORTED(fsap, f_files);
- VFSATTR_SET_SUPPORTED(fsap, f_ffree);
-
- return (0);
-}
-
-/*
- * XXX - Assumes no data cached at union layer.
- */
-#define union_sync (int (*) (mount_t, int, vfs_context_t))nullop
-
-#define union_fhtovp (int (*) (mount_t, int, unsigned char *, vnode_t *, vfs_context_t))eopnotsupp
-#define union_sysctl (int (*) (int *, u_int, user_addr_t, size_t *, user_addr_t, size_t, vfs_context_t))eopnotsupp
-#define union_vget (int (*) (mount_t, ino64_t, vnode_t *, vfs_context_t))eopnotsupp
-#define union_vptofh (int (*) (vnode_t, int *, unsigned char *, vfs_context_t))eopnotsupp
-
-struct vfsops union_vfsops = {
- union_mount,
- union_start,
- union_unmount,
- union_root,
- NULL, /* quotactl */
- union_vfs_getattr,
- union_sync,
- union_vget,
- union_fhtovp,
- union_vptofh,
- union_init,
- union_sysctl,
- NULL,
- {NULL}
-};
-
-
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