xref: /freebsd/sys/fs/unionfs/union.h (revision b28624fde638caadd4a89f50c9b7e7da0f98c4d2)
1 /*-
2  * Copyright (c) 1994 The Regents of the University of California.
3  * Copyright (c) 1994 Jan-Simon Pendry.
4  * Copyright (c) 2005, 2006 Masanori Ozawa <ozawa@ongs.co.jp>, ONGS Inc.
5  * Copyright (c) 2006 Daichi Goto <daichi@freebsd.org>
6  * All rights reserved.
7  *
8  * This code is derived from software donated to Berkeley by
9  * Jan-Simon Pendry.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)union.h	8.9 (Berkeley) 12/10/94
36  * $FreeBSD$
37  */
38 
39 #ifdef _KERNEL
40 
41 /* copy method of attr from lower to upper */
42 typedef enum _unionfs_copymode {
43 	UNIONFS_TRADITIONAL = 0,
44 	UNIONFS_TRANSPARENT,
45 	UNIONFS_MASQUERADE
46 } unionfs_copymode;
47 
48 struct unionfs_mount {
49 	struct vnode   *um_lowervp;	/* VREFed once */
50 	struct vnode   *um_uppervp;	/* VREFed once */
51 	struct vnode   *um_rootvp;	/* ROOT vnode */
52 	unionfs_copymode um_copymode;
53 	uid_t		um_uid;
54 	gid_t		um_gid;
55 	u_short		um_udir;
56 	u_short		um_ufile;
57 };
58 
59 /* unionfs status list */
60 struct unionfs_node_status {
61 	LIST_ENTRY(unionfs_node_status) uns_list;	/* Status list */
62 	lwpid_t		uns_tid;		/* current thread id */
63 	int		uns_node_flag;		/* uns flag */
64 	int		uns_lower_opencnt;	/* open count of lower */
65 	int		uns_upper_opencnt;	/* open count of upper */
66 	int		uns_lower_openmode;	/* open mode of lower */
67 	int		uns_readdir_status;	/* read status of readdir */
68 };
69 
70 /* union node status flags */
71 #define	UNS_OPENL_4_READDIR	0x01	/* open lower layer for readdir */
72 
73 /* A cache of vnode references */
74 struct unionfs_node {
75 	LIST_ENTRY(unionfs_node) un_hash;	/* Hash list */
76 	struct vnode   *un_lowervp;		/* lower side vnode */
77 	struct vnode   *un_uppervp;		/* upper side vnode */
78 	struct vnode   *un_dvp;			/* parent unionfs vnode */
79 	struct vnode   *un_vnode;		/* Back pointer */
80 	LIST_HEAD(, unionfs_node_status) un_unshead;  /* unionfs status head */
81 	char           *un_path;		/* path */
82 	int		un_flag;		/* unionfs node flag */
83 };
84 
85 /* unionfs node flags */
86 #define UNIONFS_CACHED		0x01	/* is cached */
87 #define UNIONFS_OPENEXTL	0x02	/* openextattr (lower) */
88 #define UNIONFS_OPENEXTU	0x04	/* openextattr (upper) */
89 
90 #define	MOUNTTOUNIONFSMOUNT(mp) ((struct unionfs_mount *)((mp)->mnt_data))
91 #define	VTOUNIONFS(vp) ((struct unionfs_node *)(vp)->v_data)
92 #define	UNIONFSTOV(xp) ((xp)->un_vnode)
93 
94 int unionfs_init(struct vfsconf *vfsp);
95 int unionfs_uninit(struct vfsconf *vfsp);
96 int unionfs_nodeget(struct mount *mp, struct vnode *uppervp, struct vnode *lowervp, struct vnode *dvp, struct vnode **vpp, struct componentname *cnp, struct thread *td);
97 void unionfs_hashrem(struct vnode *vp, struct thread *td);
98 void unionfs_get_node_status(struct unionfs_node *unp, struct thread *td, struct unionfs_node_status **unspp);
99 void unionfs_tryrem_node_status(struct unionfs_node *unp, struct thread *td, struct unionfs_node_status *unsp);
100 
101 int unionfs_check_rmdir(struct vnode *vp, struct ucred *cred, struct thread *td);
102 int unionfs_copyfile(struct unionfs_node *unp, int docopy, struct ucred *cred, struct thread *td);
103 void unionfs_create_uppervattr_core(struct unionfs_mount *ump, struct vattr *lva, struct vattr *uva, struct thread *td);
104 int unionfs_create_uppervattr(struct unionfs_mount *ump, struct vnode *lvp, struct vattr *uva, struct ucred *cred, struct thread *td);
105 int unionfs_mkshadowdir(struct unionfs_mount *ump, struct vnode *duvp, struct unionfs_node *unp, struct componentname *cnp, struct thread *td);
106 int unionfs_mkwhiteout(struct vnode *dvp, struct componentname *cnp, struct thread *td, char *path);
107 int unionfs_relookup_for_create(struct vnode *dvp, struct componentname *cnp, struct thread *td);
108 int unionfs_relookup_for_delete(struct vnode *dvp, struct componentname *cnp, struct thread *td);
109 int unionfs_relookup_for_rename(struct vnode *dvp, struct componentname *cnp, struct thread *td);
110 
111 #ifdef DIAGNOSTIC
112 struct vnode   *unionfs_checklowervp(struct vnode *vp, char *fil, int lno);
113 struct vnode   *unionfs_checkuppervp(struct vnode *vp, char *fil, int lno);
114 #define	UNIONFSVPTOLOWERVP(vp) unionfs_checklowervp((vp), __FILE__, __LINE__)
115 #define	UNIONFSVPTOUPPERVP(vp) unionfs_checkuppervp((vp), __FILE__, __LINE__)
116 #else
117 #define	UNIONFSVPTOLOWERVP(vp) (VTOUNIONFS(vp)->un_lowervp)
118 #define	UNIONFSVPTOUPPERVP(vp) (VTOUNIONFS(vp)->un_uppervp)
119 #endif
120 
121 extern struct vop_vector unionfs_vnodeops;
122 
123 #ifdef MALLOC_DECLARE
124 MALLOC_DECLARE(M_UNIONFSNODE);
125 MALLOC_DECLARE(M_UNIONFSPATH);
126 #endif
127 
128 #ifdef UNIONFS_DEBUG
129 #define UNIONFSDEBUG(format, args...) printf(format ,## args)
130 #else
131 #define UNIONFSDEBUG(format, args...)
132 #endif				/* UNIONFS_DEBUG */
133 
134 #endif				/* _KERNEL */
135