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
|
/*-
* Copyright (c) 1994 The Regents of the University of California.
* 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.
* 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
* $FreeBSD$
*/
#define UNMNT_ABOVE 0x0001 /* Target appears above mount point */
#define UNMNT_BELOW 0x0002 /* Target appears below mount point */
#define UNMNT_REPLACE 0x0003 /* Target replaces mount point */
struct union_mount {
struct vnode *um_uppervp; /* UN_ULOCK holds locking state */
struct vnode *um_lowervp; /* Left unlocked */
struct ucred *um_cred; /* Credentials of user calling mount */
int um_cmode; /* cmask from mount process */
int um_op; /* Operation mode */
dev_t um_upperdev; /* Upper root node fsid[0]*/
};
#ifdef _KERNEL
#ifndef DIAGNOSTIC
#define DIAGNOSTIC
#endif
/*
* DEFDIRMODE is the mode bits used to create a shadow directory.
*/
#define VRWXMODE (VREAD|VWRITE|VEXEC)
#define VRWMODE (VREAD|VWRITE)
#define UN_DIRMODE ((VRWXMODE)|(VRWXMODE>>3)|(VRWXMODE>>6))
#define UN_FILEMODE ((VRWMODE)|(VRWMODE>>3)|(VRWMODE>>6))
/*
* A cache of vnode references (hangs off v_data)
*/
struct union_node {
LIST_ENTRY(union_node) un_cache; /* Hash chain */
struct vnode *un_vnode; /* Back pointer */
struct vnode *un_uppervp; /* overlaying object */
struct vnode *un_lowervp; /* underlying object */
struct vnode *un_dirvp; /* Parent dir of uppervp */
struct vnode *un_pvp; /* Parent vnode */
char *un_path; /* saved component name */
int un_openl; /* # of opens on lowervp */
int un_exclcnt; /* exclusive count */
unsigned int un_flags;
struct vnode **un_dircache; /* cached union stack */
off_t un_uppersz; /* size of upper object */
off_t un_lowersz; /* size of lower object */
#ifdef DIAGNOSTIC
pid_t un_pid;
#endif
};
/*
* XXX UN_ULOCK - indicates that the uppervp is locked
*
* UN_CACHED - node is in the union cache
*/
/*#define UN_ULOCK 0x04*/ /* Upper node is locked */
#define UN_CACHED 0x10 /* In union cache */
/*
* Hash table locking flags
*/
#define UNVP_WANT 0x01
#define UNVP_LOCKED 0x02
extern int union_allocvp(struct vnode **, struct mount *,
struct vnode *,
struct vnode *,
struct componentname *, struct vnode *,
struct vnode *, int);
extern int union_freevp(struct vnode *);
extern struct vnode *union_dircache_get(struct vnode *, struct thread *);
extern void union_dircache_free(struct union_node *);
extern int union_copyup(struct union_node *, int, struct ucred *,
struct thread *);
extern int union_dowhiteout(struct union_node *, struct ucred *,
struct thread *);
extern int union_mkshadow(struct union_mount *, struct vnode *,
struct componentname *, struct vnode **);
extern int union_mkwhiteout(struct union_mount *, struct vnode *,
struct componentname *, char *);
extern int union_cn_close(struct vnode *, int, struct ucred *,
struct thread *);
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);
extern int (*union_dircheckp)(struct thread *, struct vnode **,
struct file *);
#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 UDEBUG(x) if (uniondebug) printf x
#define UDEBUG_ENABLED 1
extern struct vop_vector union_vnodeops;
extern struct vfsops union_vfsops;
extern int uniondebug;
#endif /* _KERNEL */
|
