portal_vfsops.c revision 172697
1/*-
2 * Copyright (c) 1992, 1993, 1995
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software donated to Berkeley by
6 * Jan-Simon Pendry.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 *	@(#)portal_vfsops.c	8.11 (Berkeley) 5/14/95
33 *
34 * $FreeBSD: head/sys/fs/portalfs/portal_vfsops.c 172697 2007-10-16 10:54:55Z alfred $
35 */
36
37/*
38 * Portal Filesystem
39 */
40
41#include <sys/param.h>
42#include <sys/systm.h>
43#include <sys/domain.h>
44#include <sys/filedesc.h>
45#include <sys/kernel.h>
46#include <sys/lock.h>
47#include <sys/mutex.h>
48#include <sys/malloc.h>
49#include <sys/file.h>		/* Must come after sys/malloc.h */
50#include <sys/mount.h>
51#include <sys/proc.h>
52#include <sys/protosw.h>
53#include <sys/socket.h>
54#include <sys/socketvar.h>
55#include <sys/vnode.h>
56
57#include <fs/portalfs/portal.h>
58
59static MALLOC_DEFINE(M_PORTALFSMNT, "portal_mount", "PORTAL mount structure");
60
61static vfs_unmount_t	portal_unmount;
62static vfs_root_t	portal_root;
63static vfs_statfs_t	portal_statfs;
64
65static const char *portal_opts[] = {
66	"socket", "config",
67	NULL
68};
69
70static int
71portal_cmount(struct mntarg *ma, void *data, int flags, struct thread *td)
72{
73	struct portal_args args;
74	int error;
75
76	if (data == NULL)
77		return (EINVAL);
78	error = copyin(data, &args, sizeof args);
79	if (error)
80		return (error);
81
82	ma = mount_argf(ma, "socket", "%d", args.pa_socket);
83	ma = mount_argsu(ma, "config", args.pa_config, MAXPATHLEN);
84	error = kernel_mount(ma, flags);
85
86	return (error);
87}
88
89/*
90 * Mount the per-process file descriptors (/dev/fd)
91 */
92static int
93portal_mount(struct mount *mp, struct thread *td)
94{
95	struct file *fp;
96	struct portalmount *fmp;
97	struct socket *so;
98	struct vnode *rvp;
99	struct portalnode *pn;
100	int error, v;
101	char *p;
102
103	if (vfs_filteropt(mp->mnt_optnew, portal_opts))
104		return (EINVAL);
105
106	error = vfs_scanopt(mp->mnt_optnew, "socket", "%d", &v);
107	if (error != 1)
108		return (EINVAL);
109	error = vfs_getopt(mp->mnt_optnew, "config", (void **)&p, NULL);
110	if (error)
111		return (error);
112
113	if ((error = fget(td, v, &fp)) != 0)
114		return (error);
115        if (fp->f_type != DTYPE_SOCKET) {
116		fdrop(fp, td);
117                return(ENOTSOCK);
118	}
119	so = fp->f_data;	/* XXX race against userland */
120	if (so->so_proto->pr_domain->dom_family != AF_UNIX) {
121		fdrop(fp, td);
122		return (ESOCKTNOSUPPORT);
123	}
124
125	MALLOC(pn, struct portalnode *, sizeof(struct portalnode),
126		M_TEMP, M_WAITOK);
127
128	MALLOC(fmp, struct portalmount *, sizeof(struct portalmount),
129		M_PORTALFSMNT, M_WAITOK);	/* XXX */
130
131	error = getnewvnode("portal", mp, &portal_vnodeops, &rvp); /* XXX */
132	if (error) {
133		FREE(fmp, M_PORTALFSMNT);
134		FREE(pn, M_TEMP);
135		fdrop(fp, td);
136		return (error);
137	}
138
139	error = insmntque(rvp, mp);	/* XXX: Too early for mpsafe fs */
140	if (error != 0) {
141		FREE(fmp, M_PORTALFSMNT);
142		FREE(pn, M_TEMP);
143		fdrop(fp, td);
144		return (error);
145	}
146	rvp->v_data = pn;
147	rvp->v_type = VDIR;
148	rvp->v_vflag |= VV_ROOT;
149	VTOPORTAL(rvp)->pt_arg = 0;
150	VTOPORTAL(rvp)->pt_size = 0;
151	VTOPORTAL(rvp)->pt_fileid = PORTAL_ROOTFILEID;
152	fmp->pm_root = rvp;
153	fhold(fp);
154	fmp->pm_server = fp;
155
156	MNT_ILOCK(mp);
157	mp->mnt_flag |= MNT_LOCAL;
158	MNT_IUNLOCK(mp);
159	mp->mnt_data =  fmp;
160	vfs_getnewfsid(mp);
161
162	vfs_mountedfrom(mp, p);
163	fdrop(fp, td);
164	return (0);
165}
166
167static int
168portal_unmount(mp, mntflags, td)
169	struct mount *mp;
170	int mntflags;
171	struct thread *td;
172{
173	int error, flags = 0;
174
175
176	if (mntflags & MNT_FORCE)
177		flags |= FORCECLOSE;
178
179	/*
180	 * Clear out buffer cache.  I don't think we
181	 * ever get anything cached at this level at the
182	 * moment, but who knows...
183	 */
184#ifdef notyet
185	mntflushbuf(mp, 0);
186	if (mntinvalbuf(mp, 1))
187		return (EBUSY);
188#endif
189	/* There is 1 extra root vnode reference (pm_root). */
190	error = vflush(mp, 1, flags, td);
191	if (error)
192		return (error);
193
194	/*
195	 * Shutdown the socket.  This will cause the select in the
196	 * daemon to wake up, and then the accept will get ECONNABORTED
197	 * which it interprets as a request to go and bury itself.
198	 */
199	soshutdown(VFSTOPORTAL(mp)->pm_server->f_data, 2);
200	/*
201	 * Discard reference to underlying file.  Must call closef because
202	 * this may be the last reference.
203	 */
204	closef(VFSTOPORTAL(mp)->pm_server, (struct thread *) 0);
205	/*
206	 * Finally, throw away the portalmount structure
207	 */
208	free(mp->mnt_data, M_PORTALFSMNT);	/* XXX */
209	mp->mnt_data = 0;
210	return (0);
211}
212
213static int
214portal_root(mp, flags, vpp, td)
215	struct mount *mp;
216	int flags;
217	struct vnode **vpp;
218	struct thread *td;
219{
220	struct vnode *vp;
221
222	/*
223	 * Return locked reference to root.
224	 */
225	vp = VFSTOPORTAL(mp)->pm_root;
226	VREF(vp);
227	vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
228	*vpp = vp;
229	return (0);
230}
231
232static int
233portal_statfs(mp, sbp, td)
234	struct mount *mp;
235	struct statfs *sbp;
236	struct thread *td;
237{
238
239	sbp->f_flags = 0;
240	sbp->f_bsize = DEV_BSIZE;
241	sbp->f_iosize = DEV_BSIZE;
242	sbp->f_blocks = 2;		/* 1K to keep df happy */
243	sbp->f_bfree = 0;
244	sbp->f_bavail = 0;
245	sbp->f_files = 1;		/* Allow for "." */
246	sbp->f_ffree = 0;		/* See comments above */
247	return (0);
248}
249
250static struct vfsops portal_vfsops = {
251	.vfs_cmount =		portal_cmount,
252	.vfs_mount =		portal_mount,
253	.vfs_root =		portal_root,
254	.vfs_statfs =		portal_statfs,
255	.vfs_unmount =		portal_unmount,
256};
257
258VFS_SET(portal_vfsops, portalfs, VFCF_SYNTHETIC);
259