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 * %sccs.include.redist.c%
9 *
10 * @(#)kernfs_vfsops.c 8.10 (Berkeley) 05/14/95
11 */
12
13 /*
14 * Kernel params Filesystem
15 */
16
17 #include <sys/param.h>
18 #include <sys/systm.h>
19 #include <sys/conf.h>
20 #include <sys/types.h>
21 #include <sys/proc.h>
22 #include <sys/vnode.h>
23 #include <sys/mount.h>
24 #include <sys/namei.h>
25 #include <sys/malloc.h>
26
27 #include <miscfs/specfs/specdev.h>
28 #include <miscfs/kernfs/kernfs.h>
29
30 dev_t rrootdev = NODEV;
31
32 kernfs_init(vfsp)
33 struct vfsconf *vfsp;
34 {
35
36 return (0);
37 }
38
39 void
kernfs_get_rrootdev()40 kernfs_get_rrootdev()
41 {
42 static int tried = 0;
43 int cmaj;
44
45 if (tried) {
46 /* Already did it once. */
47 return;
48 }
49 tried = 1;
50
51 if (rootdev == NODEV)
52 return;
53 for (cmaj = 0; cmaj < nchrdev; cmaj++) {
54 rrootdev = makedev(cmaj, minor(rootdev));
55 if (chrtoblk(rrootdev) == rootdev)
56 return;
57 }
58 rrootdev = NODEV;
59 printf("kernfs_get_rrootdev: no raw root device\n");
60 }
61
62 /*
63 * Mount the Kernel params filesystem
64 */
65 kernfs_mount(mp, path, data, ndp, p)
66 struct mount *mp;
67 char *path;
68 caddr_t data;
69 struct nameidata *ndp;
70 struct proc *p;
71 {
72 int error = 0;
73 u_int size;
74 struct kernfs_mount *fmp;
75 struct vnode *rvp;
76
77 #ifdef KERNFS_DIAGNOSTIC
78 printf("kernfs_mount(mp = %x)\n", mp);
79 #endif
80
81 /*
82 * Update is a no-op
83 */
84 if (mp->mnt_flag & MNT_UPDATE)
85 return (EOPNOTSUPP);
86
87 error = getnewvnode(VT_KERNFS, mp, kernfs_vnodeop_p, &rvp); /* XXX */
88 if (error)
89 return (error);
90
91 MALLOC(fmp, struct kernfs_mount *, sizeof(struct kernfs_mount),
92 M_UFSMNT, M_WAITOK); /* XXX */
93 rvp->v_type = VDIR;
94 rvp->v_flag |= VROOT;
95 #ifdef KERNFS_DIAGNOSTIC
96 printf("kernfs_mount: root vp = %x\n", rvp);
97 #endif
98 fmp->kf_root = rvp;
99 mp->mnt_flag |= MNT_LOCAL;
100 mp->mnt_data = (qaddr_t) fmp;
101 vfs_getnewfsid(mp);
102
103 (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
104 bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
105 bzero(mp->mnt_stat.f_mntfromname, MNAMELEN);
106 bcopy("kernfs", mp->mnt_stat.f_mntfromname, sizeof("kernfs"));
107 #ifdef KERNFS_DIAGNOSTIC
108 printf("kernfs_mount: at %s\n", mp->mnt_stat.f_mntonname);
109 #endif
110
111 kernfs_get_rrootdev();
112 return (0);
113 }
114
115 kernfs_start(mp, flags, p)
116 struct mount *mp;
117 int flags;
118 struct proc *p;
119 {
120 return (0);
121 }
122
123 kernfs_unmount(mp, mntflags, p)
124 struct mount *mp;
125 int mntflags;
126 struct proc *p;
127 {
128 int error;
129 int flags = 0;
130 struct vnode *rootvp = VFSTOKERNFS(mp)->kf_root;
131
132 #ifdef KERNFS_DIAGNOSTIC
133 printf("kernfs_unmount(mp = %x)\n", mp);
134 #endif
135
136 if (mntflags & MNT_FORCE)
137 flags |= FORCECLOSE;
138
139 /*
140 * Clear out buffer cache. I don't think we
141 * ever get anything cached at this level at the
142 * moment, but who knows...
143 */
144 if (rootvp->v_usecount > 1)
145 return (EBUSY);
146 #ifdef KERNFS_DIAGNOSTIC
147 printf("kernfs_unmount: calling vflush\n");
148 #endif
149 if (error = vflush(mp, rootvp, flags))
150 return (error);
151
152 #ifdef KERNFS_DIAGNOSTIC
153 vprint("kernfs root", rootvp);
154 #endif
155 /*
156 * Release reference on underlying root vnode
157 */
158 vrele(rootvp);
159 /*
160 * And blow it away for future re-use
161 */
162 vgone(rootvp);
163 /*
164 * Finally, throw away the kernfs_mount structure
165 */
166 free(mp->mnt_data, M_UFSMNT); /* XXX */
167 mp->mnt_data = 0;
168 return 0;
169 }
170
171 kernfs_root(mp, vpp)
172 struct mount *mp;
173 struct vnode **vpp;
174 {
175 struct proc *p = curproc; /* XXX */
176 struct vnode *vp;
177
178 #ifdef KERNFS_DIAGNOSTIC
179 printf("kernfs_root(mp = %x)\n", mp);
180 #endif
181
182 /*
183 * Return locked reference to root.
184 */
185 vp = VFSTOKERNFS(mp)->kf_root;
186 VREF(vp);
187 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p);
188 *vpp = vp;
189 return (0);
190 }
191
192 kernfs_statfs(mp, sbp, p)
193 struct mount *mp;
194 struct statfs *sbp;
195 struct proc *p;
196 {
197 #ifdef KERNFS_DIAGNOSTIC
198 printf("kernfs_statfs(mp = %x)\n", mp);
199 #endif
200
201 sbp->f_flags = 0;
202 sbp->f_bsize = DEV_BSIZE;
203 sbp->f_iosize = DEV_BSIZE;
204 sbp->f_blocks = 2; /* 1K to keep df happy */
205 sbp->f_bfree = 0;
206 sbp->f_bavail = 0;
207 sbp->f_files = 0;
208 sbp->f_ffree = 0;
209 if (sbp != &mp->mnt_stat) {
210 sbp->f_type = mp->mnt_vfc->vfc_typenum;
211 bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid));
212 bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
213 bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
214 }
215 return (0);
216 }
217
218 struct vfsops kernfs_vfsops = {
219 kernfs_mount,
220 kernfs_start,
221 kernfs_unmount,
222 kernfs_root,
223 kernfs_quotactl,
224 kernfs_statfs,
225 kernfs_sync,
226 kernfs_vget,
227 kernfs_fhtovp,
228 kernfs_vptofh,
229 kernfs_init,
230 kernfs_sysctl,
231 };
232