HAMMER 60I/Many: Mirroring
[dragonfly.git] / sys / vfs / fdesc / fdesc_vfsops.c
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1 /*
2 * Copyright (c) 1992, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software donated to Berkeley by
6 * Jan-Simon Pendry.
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 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
36 * @(#)fdesc_vfsops.c 8.4 (Berkeley) 1/21/94
38 * $FreeBSD: src/sys/miscfs/fdesc/fdesc_vfsops.c,v 1.22.2.3 2002/08/23 17:42:39 njl Exp $
39 * $DragonFly: src/sys/vfs/fdesc/fdesc_vfsops.c,v 1.22 2006/09/05 00:55:50 dillon Exp $
43 * /dev/fd Filesystem
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/filedesc.h>
49 #include <sys/kernel.h>
50 #include <sys/lock.h>
51 #include <sys/malloc.h>
52 #include <sys/mount.h>
53 #include <sys/proc.h>
54 #include <sys/resourcevar.h>
55 #include <sys/socket.h>
56 #include <sys/vnode.h>
58 #include "fdesc.h"
60 extern struct vop_ops fdesc_vnode_vops;
62 static MALLOC_DEFINE(M_FDESCMNT, "FDESC mount", "FDESC mount structure");
64 static int fdesc_mount (struct mount *mp, char *path, caddr_t data,
65 struct ucred *cred);
66 static int fdesc_unmount (struct mount *mp, int mntflags);
67 static int fdesc_statfs (struct mount *mp, struct statfs *sbp,
68 struct ucred *cred);
71 * Mount the per-process file descriptors (/dev/fd)
73 static int
74 fdesc_mount(struct mount *mp, char *path, caddr_t data, struct ucred *cred)
76 int error = 0;
77 struct fdescmount *fmp;
78 struct vnode *rvp;
80 if (path == NULL)
81 panic("fdesc_mount: cannot mount as root");
84 * Update is a no-op
86 if (mp->mnt_flag & MNT_UPDATE)
87 return (EOPNOTSUPP);
89 vfs_add_vnodeops(mp, &fdesc_vnode_vops, &mp->mnt_vn_norm_ops);
91 error = fdesc_allocvp(Froot, FD_ROOT, mp, &rvp);
92 if (error)
93 return (error);
95 MALLOC(fmp, struct fdescmount *, sizeof(struct fdescmount),
96 M_FDESCMNT, M_WAITOK); /* XXX */
97 rvp->v_type = VDIR;
98 rvp->v_flag |= VROOT;
99 fmp->f_root = rvp;
100 /* XXX -- don't mark as local to work around fts() problems */
101 /*mp->mnt_flag |= MNT_LOCAL;*/
102 mp->mnt_data = (qaddr_t) fmp;
103 vfs_getnewfsid(mp);
105 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
106 bcopy("fdesc", mp->mnt_stat.f_mntfromname, sizeof("fdesc"));
107 fdesc_statfs(mp, &mp->mnt_stat, cred);
108 return (0);
111 static int
112 fdesc_unmount(struct mount *mp, int mntflags)
114 int error;
115 int flags = 0;
117 if (mntflags & MNT_FORCE)
118 flags |= FORCECLOSE;
121 * Clear out buffer cache. I don't think we
122 * ever get anything cached at this level at the
123 * moment, but who knows...
125 * There is 1 extra root vnode reference corresponding
126 * to f_root.
128 if ((error = vflush(mp, 1, flags)) != 0)
129 return (error);
132 * Finally, throw away the fdescmount structure
134 kfree(mp->mnt_data, M_FDESCMNT); /* XXX */
135 mp->mnt_data = 0;
137 return (0);
141 fdesc_root(struct mount *mp, struct vnode **vpp)
143 struct vnode *vp;
144 int error;
147 * Return locked reference to root.
149 vp = VFSTOFDESC(mp)->f_root;
150 error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
151 if (error == 0)
152 *vpp = vp;
153 return (error);
156 static int
157 fdesc_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
159 sbp->f_flags = 0;
160 sbp->f_bsize = DEV_BSIZE;
161 sbp->f_iosize = DEV_BSIZE;
162 sbp->f_blocks = 2; /* 1K to keep df happy */
163 sbp->f_bfree = 0;
164 sbp->f_bavail = 0;
165 sbp->f_files = 0; /* dummy up these fields */
166 sbp->f_ffree = 0;
167 if (sbp != &mp->mnt_stat) {
168 sbp->f_type = mp->mnt_vfc->vfc_typenum;
169 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
170 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
172 return (0);
175 static struct vfsops fdesc_vfsops = {
176 .vfs_mount = fdesc_mount,
177 .vfs_unmount = fdesc_unmount,
178 .vfs_root = fdesc_root,
179 .vfs_statfs = fdesc_statfs,
180 .vfs_sync = vfs_stdsync,
181 .vfs_init = fdesc_init,
182 .vfs_uninit = fdesc_uninit
185 VFS_SET(fdesc_vfsops, fdesc, VFCF_SYNTHETIC);