1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
/* $NetBSD: union.h,v 1.30 2020/08/18 09:44:07 hannken Exp $ */
/*
* Copyright (c) 1994 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software donated to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)union.h 8.9 (Berkeley) 12/10/94
*/
/*
* Copyright (c) 1994 Jan-Simon Pendry.
* All rights reserved.
*
* This code is derived from software donated to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)union.h 8.9 (Berkeley) 12/10/94
*/
#ifndef _MISCFS_UNION_H_
#define _MISCFS_UNION_H_
struct union_args {
char *target; /* Target of loopback */
int mntflags; /* Options on the mount */
};
#define UNMNT_ABOVE 0x0001 /* Target appears below mount point */
#define UNMNT_BELOW 0x0002 /* Target appears below mount point */
#define UNMNT_REPLACE 0x0003 /* Target replaces mount point */
#define UNMNT_OPMASK 0x0003
#define UNMNT_BITS "\177\20" \
"b\00above\0b\01below\0b\02replace\0"
#ifdef _KERNEL
struct union_mount {
struct vnode *um_uppervp;
struct vnode *um_lowervp;
kauth_cred_t um_cred; /* Credentials of user calling mount */
int um_cmode; /* cmask from mount process */
int um_op; /* Operation mode */
};
/*
* DEFDIRMODE is the mode bits used to create a shadow directory.
*/
#define UN_DIRMODE (S_IRWXU|S_IRWXG|S_IRWXO)
#define UN_FILEMODE (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)
/*
* A cache of vnode references.
* Lock requirements are:
*
* : stable
* c unheadlock[hash]
* l un_lock
* m un_lock or vnode lock to read, un_lock and
* exclusive vnode lock to write
* v vnode lock to read, exclusive vnode lock to write
*
* Lock order is vnode then un_lock.
*/
struct union_node {
kmutex_t un_lock;
LIST_ENTRY(union_node) un_cache; /* c: Hash chain */
int un_refs; /* c: Reference counter */
struct mount *un_mount; /* c: union mount */
struct vnode *un_vnode; /* :: Back pointer */
struct vnode *un_uppervp; /* m: overlaying object */
struct vnode *un_lowervp; /* v: underlying object */
struct vnode *un_dirvp; /* v: Parent dir of uppervp */
struct vnode *un_pvp; /* v: Parent vnode */
char *un_path; /* v: saved component name */
int un_openl; /* v: # of opens on lowervp */
unsigned int un_cflags; /* c: cache flags */
bool un_hooknode; /* :: from union_readdirhook */
struct vnode **un_dircache; /* v: cached union stack */
off_t un_uppersz; /* l: size of upper object */
off_t un_lowersz; /* l: size of lower object */
};
#define UN_CACHED 0x10 /* In union cache */
extern int union_allocvp(struct vnode **, struct mount *,
struct vnode *, struct vnode *,
struct componentname *, struct vnode *,
struct vnode *, int);
extern int union_check_rmdir(struct union_node *, kauth_cred_t);
extern int union_copyfile(struct vnode *, struct vnode *, kauth_cred_t,
struct lwp *);
extern int union_copyup(struct union_node *, int, kauth_cred_t,
struct lwp *);
extern void union_diruncache(struct union_node *);
extern int union_dowhiteout(struct union_node *, kauth_cred_t);
extern int union_mkshadow(struct union_mount *, struct vnode *,
struct componentname *, struct vnode **);
extern int union_mkwhiteout(struct union_mount *, struct vnode *,
struct componentname *, struct union_node *);
extern int union_vn_create(struct vnode **, struct union_node *,
struct lwp *);
extern int union_cn_close(struct vnode *, int, kauth_cred_t,
struct lwp *);
extern void union_removed_upper(struct union_node *un);
extern struct vnode *union_lowervp(struct vnode *);
extern void union_newsize(struct vnode *, off_t, off_t);
int union_readdirhook(struct vnode **, struct file *, struct lwp *);
VFS_PROTOS(union);
#define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data))
#define VTOUNION(vp) ((struct union_node *)(vp)->v_data)
#define UNIONTOV(un) ((un)->un_vnode)
#define LOWERVP(vp) (VTOUNION(vp)->un_lowervp)
#define UPPERVP(vp) (VTOUNION(vp)->un_uppervp)
#define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp))
#define LOCKVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : (vp))
extern int (**union_vnodeop_p)(void *);
void union_init(void);
void union_reinit(void);
void union_done(void);
int union_freevp(struct vnode *);
#endif /* _KERNEL */
#endif /* _MISCFS_UNION_H_ */
|
