[unix-history] / usr / src / sys / deprecated / lofs / lofs_vfsops.c

/*
 * Copyright (c) 1992, 1993
 *	The Regents of the University of California.  All rights reserved.
 * All rights reserved.
 *
 * This code is derived from software donated to Berkeley by
 * Jan-Simon Pendry.
 *
 * %sccs.include.redist.c%
 *
 *	@(#)lofs_vfsops.c	8.1 (Berkeley) %G%
 *
 * $Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp jsp $
 */

/*
 * Loopback Filesystem
 */

#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 <miscfs/lofs/lofs.h>

/*
 * Mount loopback copy of existing name space
 */
lofs_mount(mp, path, data, ndp, p)
	struct mount *mp;
	char *path;
	caddr_t data;
	struct nameidata *ndp;
	struct proc *p;
{
	int error = 0;
	struct lofs_args args;
	struct vnode *vp;
	struct vnode *rootvp;
	struct lofsmount *amp;
	u_int size;

#ifdef LOFS_DIAGNOSTIC
	printf("lofs_mount(mp = %x)\n", mp);
#endif

	/*
	 * Update is a no-op
	 */
	if (mp->mnt_flag & MNT_UPDATE) {
		return (EOPNOTSUPP);
		/* return VFS_MOUNT(VFSTOLOFS(mp)->looped_vfs, path, data, ndp, p);*/
	}

	/*
	 * Get argument
	 */
	if (error = copyin(data, (caddr_t)&args, sizeof(struct lofs_args)))
		return (error);

	/*
	 * Find target node
	 */
	NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF,
		UIO_USERSPACE, args.target, p);
	if (error = namei(ndp))
		return (error);

	/*
	 * Sanity check on target vnode
	 */
	vp = ndp->ni_vp;
#ifdef LOFS_DIAGNOSTIC
	printf("vp = %x, check for VDIR...\n", vp);
#endif
	vrele(ndp->ni_dvp);
	ndp->ni_dvp = 0;

	if (vp->v_type != VDIR) {
		vput(vp);
		return (EINVAL);
	}

#ifdef LOFS_DIAGNOSTIC
	printf("mp = %x\n", mp);
#endif

	amp = (struct lofsmount *) malloc(sizeof(struct lofsmount),
				M_UFSMNT, M_WAITOK);	/* XXX */

	/*
	 * Save reference to underlying target FS
	 */
	amp->looped_vfs = vp->v_mount;

	/*
	 * Save reference.  Each mount also holds
	 * a reference on the root vnode.
	 */
	error = make_lofs(mp, &vp);
	/*
	 * Unlock the node (either the target or the alias)
	 */
	VOP_UNLOCK(vp);
	/*
	 * Make sure the node alias worked
	 */
	if (error) {
		vrele(vp);
		free(amp, M_UFSMNT);	/* XXX */
		return (error);
	}

	/*
	 * Keep a held reference to the root vnode.
	 * It is vrele'd in lofs_unmount.
	 */
	rootvp = vp;
	rootvp->v_flag |= VROOT;
	amp->rootvp = rootvp;
	if (LOFSVP(rootvp)->v_mount->mnt_flag & MNT_LOCAL)
		mp->mnt_flag |= MNT_LOCAL;
	mp->mnt_data = (qaddr_t) amp;
	getnewfsid(mp, MOUNT_LOFS);

	(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
	(void) copyinstr(args.target, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, 
	    &size);
	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
#ifdef LOFS_DIAGNOSTIC
	printf("lofs_mount: target %s, alias at %s\n",
		mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
#endif
	return (0);
}

/*
 * VFS start.  Nothing needed here - the start routine
 * on the underlying filesystem will have been called
 * when that filesystem was mounted.
 */
lofs_start(mp, flags, p)
	struct mount *mp;
	int flags;
	struct proc *p;
{
	return (0);
	/* return VFS_START(VFSTOLOFS(mp)->looped_vfs, flags, p); */
}

/*
 * Free reference to looped FS
 */
lofs_unmount(mp, mntflags, p)
	struct mount *mp;
	int mntflags;
	struct proc *p;
{
	struct vnode *rootvp = VFSTOLOFS(mp)->rootvp;
	int error;
	int flags = 0;
	extern int doforce;

#ifdef LOFS_DIAGNOSTIC
	printf("lofs_unmount(mp = %x)\n", mp);
#endif

	if (mntflags & MNT_FORCE) {
		/* lofs can never be rootfs so don't check for it */
		if (!doforce)
			return (EINVAL);
		flags |= FORCECLOSE;
	}

	/*
	 * Clear out buffer cache.  I don't think we
	 * ever get anything cached at this level at the
	 * moment, but who knows...
	 */
	if (rootvp->v_usecount > 1)
		return (EBUSY);
	if (error = vflush(mp, rootvp, flags))
		return (error);

#ifdef LOFS_DIAGNOSTIC
	/*
	 * Flush any remaining vnode references
	 */
	lofs_flushmp(mp);
#endif

#ifdef LOFS_DIAGNOSTIC
	vprint("alias root of target", rootvp);
#endif	 
	/*
	 * Release reference on underlying root vnode
	 */
	vrele(rootvp);
	/*
	 * And blow it away for future re-use
	 */
	vgone(rootvp);
	/*
	 * Finally, throw away the lofsmount structure
	 */
	free(mp->mnt_data, M_UFSMNT);	/* XXX */
	mp->mnt_data = 0;
	return 0;
}

lofs_root(mp, vpp)
	struct mount *mp;
	struct vnode **vpp;
{
	struct vnode *vp;

#ifdef LOFS_DIAGNOSTIC
	printf("lofs_root(mp = %x, vp = %x->%x)\n", mp,
			VFSTOLOFS(mp)->rootvp,
			LOFSVP(VFSTOLOFS(mp)->rootvp)
			);
#endif

	/*
	 * Return locked reference to root.
	 */
	vp = VFSTOLOFS(mp)->rootvp;
	VREF(vp);
	VOP_LOCK(vp);
	*vpp = vp;
	return 0;
}

lofs_quotactl(mp, cmd, uid, arg, p)
	struct mount *mp;
	int cmd;
	uid_t uid;
	caddr_t arg;
	struct proc *p;
{
	return VFS_QUOTACTL(VFSTOLOFS(mp)->looped_vfs, cmd, uid, arg, p);
}

lofs_statfs(mp, sbp, p)
	struct mount *mp;
	struct statfs *sbp;
	struct proc *p;
{
	int error;
	struct statfs mstat;

#ifdef LOFS_DIAGNOSTIC
	printf("lofs_statfs(mp = %x, vp = %x->%x)\n", mp,
			VFSTOLOFS(mp)->rootvp,
			LOFSVP(VFSTOLOFS(mp)->rootvp)
			);
#endif

	bzero(&mstat, sizeof(mstat));

	error = VFS_STATFS(VFSTOLOFS(mp)->looped_vfs, &mstat, p);
	if (error)
		return (error);

	/* now copy across the "interesting" information and fake the rest */
	sbp->f_type = mstat.f_type;
	sbp->f_flags = mstat.f_flags;
	sbp->f_bsize = mstat.f_bsize;
	sbp->f_iosize = mstat.f_iosize;
	sbp->f_blocks = mstat.f_blocks;
	sbp->f_bfree = mstat.f_bfree;
	sbp->f_bavail = mstat.f_bavail;
	sbp->f_files = mstat.f_files;
	sbp->f_ffree = mstat.f_ffree;
	if (sbp != &mp->mnt_stat) {
		bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
	}
	return (0);
}

lofs_sync(mp, waitfor)
struct mount *mp;
int waitfor;
{
	return (0);
}

/*
 * LOFS flat namespace lookup.
 * Currently unsupported.
 */
lofs_vget(mp, ino, vpp)
	struct mount *mp;
	ino_t ino;
	struct vnode **vpp;
{

	return (EOPNOTSUPP);
}

lofs_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
	register struct mount *mp;
	struct fid *fhp;
	struct mbuf *nam;
	struct vnode **vpp;
	int *exflagsp;
	struct ucred **credanonp;
{
	return VFS_FHTOVP(VFSTOLOFS(mp)->looped_vfs, fhp, nam, vpp, exflagsp, credanonp);
}

lofs_vptofh(vp, fhp)
	struct vnode *vp;
	struct fid *fhp;
{
	return VFS_VPTOFH(LOFSVP(vp), fhp);
}

int lofs_init __P((void));

struct vfsops lofs_vfsops = {
	lofs_mount,
	lofs_start,
	lofs_unmount,
	lofs_root,
	lofs_quotactl,
	lofs_statfs,
	lofs_sync,
	lofs_vget,
	lofs_fhtovp,
	lofs_vptofh,
	lofs_init,
};
Commit	Line	Data
6764856a	1	/*
99315dca KB	2	* Copyright (c) 1992, 1993
99315dca KB	3	* The Regents of the University of California. All rights reserved.
6764856a JSP	4	* All rights reserved.
	5	*
	6	* This code is derived from software donated to Berkeley by
	7	* Jan-Simon Pendry.
	8	*
	9	* %sccs.include.redist.c%
	10	*
99315dca	11	* @(#)lofs_vfsops.c 8.1 (Berkeley) %G%
6764856a JSP	12	*
	13	* $Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp jsp $
	14	*/
	15
	16	/*
	17	* Loopback Filesystem
	18	*/
	19
	20	#include <sys/param.h>
	21	#include <sys/systm.h>
	22	#include <sys/time.h>
	23	#include <sys/types.h>
	24	#include <sys/vnode.h>
	25	#include <sys/mount.h>
	26	#include <sys/namei.h>
	27	#include <sys/malloc.h>
6681df29	28	#include <miscfs/lofs/lofs.h>
6764856a JSP	29
	30	/*
	31	* Mount loopback copy of existing name space
	32	*/
	33	lofs_mount(mp, path, data, ndp, p)
	34	struct mount *mp;
	35	char *path;
	36	caddr_t data;
	37	struct nameidata *ndp;
	38	struct proc *p;
	39	{
6764856a JSP	40	int error = 0;
	41	struct lofs_args args;
	42	struct vnode *vp;
	43	struct vnode *rootvp;
	44	struct lofsmount *amp;
	45	u_int size;
	46
	47	#ifdef LOFS_DIAGNOSTIC
	48	printf("lofs_mount(mp = %x)\n", mp);
	49	#endif
	50
	51	/*
	52	* Update is a no-op
	53	*/
	54	if (mp->mnt_flag & MNT_UPDATE) {
	55	return (EOPNOTSUPP);
	56	/* return VFS_MOUNT(VFSTOLOFS(mp)->looped_vfs, path, data, ndp, p);*/
	57	}
	58
	59	/*
	60	* Get argument
	61	*/
	62	if (error = copyin(data, (caddr_t)&args, sizeof(struct lofs_args)))
	63	return (error);
	64
	65	/*
	66	* Find target node
	67	*/
	68	NDINIT(ndp, LOOKUP, FOLLOW\|WANTPARENT\|LOCKLEAF,
	69	UIO_USERSPACE, args.target, p);
	70	if (error = namei(ndp))
	71	return (error);
	72
	73	/*
	74	* Sanity check on target vnode
	75	*/
	76	vp = ndp->ni_vp;
	77	#ifdef LOFS_DIAGNOSTIC
	78	printf("vp = %x, check for VDIR...\n", vp);
	79	#endif
	80	vrele(ndp->ni_dvp);
	81	ndp->ni_dvp = 0;
	82
	83	if (vp->v_type != VDIR) {
	84	vput(vp);
	85	return (EINVAL);
	86	}
	87
	88	#ifdef LOFS_DIAGNOSTIC
	89	printf("mp = %x\n", mp);
	90	#endif
	91
	92	amp = (struct lofsmount *) malloc(sizeof(struct lofsmount),
	93	M_UFSMNT, M_WAITOK); /* XXX */
	94
	95	/*
	96	* Save reference to underlying target FS
	97	*/
	98	amp->looped_vfs = vp->v_mount;
	99
	100	/*
	101	* Save reference. Each mount also holds
	102	* a reference on the root vnode.
	103	*/
104	error = make_lofs(mp, &vp);
105	/*
106	* Unlock the node (either the target or the alias)
107	*/
108	VOP_UNLOCK(vp);
109	/*
110	* Make sure the node alias worked
111	*/
112	if (error) {
113	vrele(vp);
114	free(amp, M_UFSMNT); /* XXX */
115	return (error);
116	}
117
118	/*
119	* Keep a held reference to the root vnode.
120	* It is vrele'd in lofs_unmount.
121	*/
122	rootvp = vp;
123	rootvp->v_flag \|= VROOT;
124	amp->rootvp = rootvp;
125	if (LOFSVP(rootvp)->v_mount->mnt_flag & MNT_LOCAL)
126	mp->mnt_flag \|= MNT_LOCAL;
127	mp->mnt_data = (qaddr_t) amp;
128	getnewfsid(mp, MOUNT_LOFS);
129
130	(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
131	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
132	(void) copyinstr(args.target, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
133	&size);
134	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
135	#ifdef LOFS_DIAGNOSTIC
136	printf("lofs_mount: target %s, alias at %s\n",
137	mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname);
138	#endif
139	return (0);
140	}
141
142	/*
143	* VFS start. Nothing needed here - the start routine
144	* on the underlying filesystem will have been called
145	* when that filesystem was mounted.
146	*/
147	lofs_start(mp, flags, p)
148	struct mount *mp;
149	int flags;
150	struct proc *p;
151	{
152	return (0);
153	/* return VFS_START(VFSTOLOFS(mp)->looped_vfs, flags, p); */
154	}
155
156	/*
157	* Free reference to looped FS
158	*/
159	lofs_unmount(mp, mntflags, p)
160	struct mount *mp;
161	int mntflags;
162	struct proc *p;
163	{
164	struct vnode *rootvp = VFSTOLOFS(mp)->rootvp;
165	int error;
166	int flags = 0;
167	extern int doforce;
168
169	#ifdef LOFS_DIAGNOSTIC
170	printf("lofs_unmount(mp = %x)\n", mp);
171	#endif
172
173	if (mntflags & MNT_FORCE) {
174	/* lofs can never be rootfs so don't check for it */
175	if (!doforce)
176	return (EINVAL);
177	flags \|= FORCECLOSE;
178	}
179
180	/*
181	* Clear out buffer cache. I don't think we
182	* ever get anything cached at this level at the
183	* moment, but who knows...
184	*/
6764856a JSP	185	if (rootvp->v_usecount > 1)
	186	return (EBUSY);
	187	if (error = vflush(mp, rootvp, flags))
	188	return (error);
	189
	190	#ifdef LOFS_DIAGNOSTIC
	191	/*
	192	* Flush any remaining vnode references
	193	*/
	194	lofs_flushmp(mp);
	195	#endif
	196
	197	#ifdef LOFS_DIAGNOSTIC
	198	vprint("alias root of target", rootvp);
	199	#endif
	200	/*
	201	* Release reference on underlying root vnode
	202	*/
	203	vrele(rootvp);
	204	/*
	205	* And blow it away for future re-use
	206	*/
	207	vgone(rootvp);
	208	/*
	209	* Finally, throw away the lofsmount structure
	210	*/
	211	free(mp->mnt_data, M_UFSMNT); /* XXX */
	212	mp->mnt_data = 0;
	213	return 0;
	214	}
	215
	216	lofs_root(mp, vpp)
	217	struct mount *mp;
	218	struct vnode **vpp;
	219	{
6764856a JSP	220	struct vnode *vp;
	221
	222	#ifdef LOFS_DIAGNOSTIC
	223	printf("lofs_root(mp = %x, vp = %x->%x)\n", mp,
	224	VFSTOLOFS(mp)->rootvp,
	225	LOFSVP(VFSTOLOFS(mp)->rootvp)
	226	);
	227	#endif
	228
	229	/*
	230	* Return locked reference to root.
	231	*/
	232	vp = VFSTOLOFS(mp)->rootvp;
	233	VREF(vp);
	234	VOP_LOCK(vp);
	235	*vpp = vp;
	236	return 0;
	237	}
	238
	239	lofs_quotactl(mp, cmd, uid, arg, p)
	240	struct mount *mp;
	241	int cmd;
	242	uid_t uid;
	243	caddr_t arg;
	244	struct proc *p;
	245	{
	246	return VFS_QUOTACTL(VFSTOLOFS(mp)->looped_vfs, cmd, uid, arg, p);
	247	}
	248
	249	lofs_statfs(mp, sbp, p)
	250	struct mount *mp;
	251	struct statfs *sbp;
	252	struct proc *p;
	253	{
	254	int error;
	255	struct statfs mstat;
	256
	257	#ifdef LOFS_DIAGNOSTIC
	258	printf("lofs_statfs(mp = %x, vp = %x->%x)\n", mp,
	259	VFSTOLOFS(mp)->rootvp,
	260	LOFSVP(VFSTOLOFS(mp)->rootvp)
	261	);
	262	#endif
	263
	264	bzero(&mstat, sizeof(mstat));
	265
	266	error = VFS_STATFS(VFSTOLOFS(mp)->looped_vfs, &mstat, p);
	267	if (error)
	268	return (error);
	269
	270	/* now copy across the "interesting" information and fake the rest */
	271	sbp->f_type = mstat.f_type;
	272	sbp->f_flags = mstat.f_flags;
	273	sbp->f_bsize = mstat.f_bsize;
	274	sbp->f_iosize = mstat.f_iosize;
	275	sbp->f_blocks = mstat.f_blocks;
	276	sbp->f_bfree = mstat.f_bfree;
	277	sbp->f_bavail = mstat.f_bavail;
	278	sbp->f_files = mstat.f_files;
	279	sbp->f_ffree = mstat.f_ffree;
	280	if (sbp != &mp->mnt_stat) {
	281	bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
	282	bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
	283	bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
284	}
285	return (0);
286	}
287
288	lofs_sync(mp, waitfor)
289	struct mount *mp;
290	int waitfor;
291	{
279e0ea4	292	return (0);
6764856a JSP	293	}
6764856a JSP	294
e28b0770 JSP	295	/*
	296	* LOFS flat namespace lookup.
	297	* Currently unsupported.
	298	*/
	299	lofs_vget(mp, ino, vpp)
6764856a	300	struct mount *mp;
e28b0770 JSP	301	ino_t ino;
	302	struct vnode **vpp;
	303	{
	304
	305	return (EOPNOTSUPP);
	306	}
	307
	308	lofs_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
	309	register struct mount *mp;
6764856a	310	struct fid *fhp;
e28b0770	311	struct mbuf *nam;
6764856a	312	struct vnode **vpp;
e28b0770 JSP	313	int *exflagsp;
e28b0770 JSP	314	struct ucred **credanonp;
6764856a	315	{
e28b0770	316	return VFS_FHTOVP(VFSTOLOFS(mp)->looped_vfs, fhp, nam, vpp, exflagsp, credanonp);
6764856a JSP	317	}
	318
	319	lofs_vptofh(vp, fhp)
	320	struct vnode *vp;
	321	struct fid *fhp;
	322	{
	323	return VFS_VPTOFH(LOFSVP(vp), fhp);
	324	}
	325
	326	int lofs_init __P((void));
	327
	328	struct vfsops lofs_vfsops = {
	329	lofs_mount,
	330	lofs_start,
	331	lofs_unmount,
	332	lofs_root,
	333	lofs_quotactl,
	334	lofs_statfs,
	335	lofs_sync,
e28b0770	336	lofs_vget,
6764856a JSP	337	lofs_fhtovp,
	338	lofs_vptofh,
	339	lofs_init,
	340	};