1 /*
2 * Copyright (c) 1989 Jan-Simon Pendry
3 * Copyright (c) 1989 Imperial College of Science, Technology & Medicine
4 * Copyright (c) 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Jan-Simon Pendry at Imperial College, London.
9 *
10 * %sccs.include.redist.c%
11 *
12 * @(#)ifs_ops.c 8.1 (Berkeley) 06/06/93
13 *
14 * $Id: ifs_ops.c,v 5.2.2.1 1992/02/09 15:08:26 jsp beta $
15 *
16 */
17
18 #include "am.h"
19
20 #ifdef HAS_IFS
21
22 /*
23 * Inheritance file system.
24 * This implements a filesystem restart.
25 *
26 * This is a *gross* hack - it knows far too
27 * much about the way other parts of the
28 * sytem work. See restart.c too.
29 */
30 static char not_a_filesystem[] = "Attempting to inherit not-a-filesystem";
31 /*
32 * This should never be called.
33 */
34 /*ARGSUSED*/
35 static char *ifs_match P((am_opts *fo));
ifs_match(fo)36 static char *ifs_match(fo)
37 am_opts *fo;
38 {
39 plog(XLOG_FATAL, "ifs_match called!");
40 return 0;
41 }
42
43 static int ifs_init P((mntfs *mf));
ifs_init(mf)44 static int ifs_init(mf)
45 mntfs *mf;
46 {
47 mntfs *mf_link = (mntfs *) mf->mf_private;
48 if (mf_link == 0) {
49 plog(XLOG_FATAL, not_a_filesystem);
50 return EINVAL;
51 }
52 #ifdef notdef
53 /*
54 * Fill in attribute fields
55 */
56 mf_link->mf_fattr.type = NFLNK;
57 mf_link->mf_fattr.mode = NFSMODE_LNK | 0777;
58 mf_link->mf_fattr.nlink = 1;
59 mf_link->mf_fattr.size = MAXPATHLEN / 4;
60 #endif
61 if (mf_link->mf_ops->fs_init)
62 return (*mf_link->mf_ops->fs_init)(mf_link);
63 return 0;
64 }
65
66 static mntfs *ifs_inherit P((mntfs *mf));
ifs_inherit(mf)67 static mntfs *ifs_inherit(mf)
68 mntfs *mf;
69 {
70 /*
71 * Take the linked mount point and
72 * propogate.
73 */
74 mntfs *mf_link = (mntfs *) mf->mf_private;
75 if (mf_link == 0) {
76 plog(XLOG_FATAL, not_a_filesystem);
77 return 0; /*XXX*/
78 }
79
80 mf_link->mf_fo = mf->mf_fo;
81 #ifdef notdef
82 mf_link->mf_fattr.fileid = mf->mf_fattr.fileid;
83 #endif /* notdef */
84
85 /*
86 * Discard the old map.
87 * Don't call am_unmounted since this
88 * node was never really mounted in the
89 * first place.
90 */
91 mf->mf_private = 0;
92 free_mntfs(mf);
93 /*
94 * Free the dangling reference
95 * to the mount link.
96 */
97 free_mntfs(mf_link);
98 /*
99 * Get a hold of the other entry
100 */
101 mf_link->mf_flags &= ~MFF_RESTART;
102
103 /* Say what happened */
104 plog(XLOG_INFO, "restarting %s on %s", mf_link->mf_info, mf_link->mf_mount);
105
106 return mf_link;
107 }
108
109 static int ifs_mount P((am_node *mp));
ifs_mount(mp)110 static int ifs_mount(mp)
111 am_node *mp;
112 {
113 mntfs *newmf = ifs_inherit(mp->am_mnt);
114 if (newmf) {
115 mp->am_mnt = newmf;
116 /*
117 * XXX - must do the am_mounted call here
118 */
119 if (newmf->mf_ops->fs_flags & FS_MBACKGROUND)
120 am_mounted(mp);
121
122 new_ttl(mp);
123 return 0;
124 }
125 return EINVAL;
126 }
127
128 static int ifs_fmount P((mntfs *mf));
ifs_fmount(mf)129 static int ifs_fmount(mf)
130 mntfs *mf;
131 {
132 am_node *mp = find_mf(mf);
133 if (mp)
134 return ifs_mount(mp);
135 return ifs_inherit(mf) ? 0 : EINVAL;
136 }
137
138 /*ARGSUSED*/
139 static int ifs_fumount P((mntfs *mf));
ifs_fumount(mf)140 static int ifs_fumount(mf)
141 mntfs *mf;
142 {
143 /*
144 * Always succeed
145 */
146 return 0;
147 }
148
149 /*
150 * Ops structure
151 */
152 am_ops ifs_ops = {
153 "inherit",
154 ifs_match,
155 ifs_init,
156 ifs_mount,
157 ifs_fmount,
158 auto_fumount,
159 ifs_fumount,
160 efs_lookuppn,
161 efs_readdir,
162 0, /* ifs_readlink */
163 0, /* ifs_mounted */
164 0, /* ifs_umounted */
165 find_afs_srvr,
166 FS_DISCARD
167 };
168
169 #endif /* HAS_IFS */
170