[apple/xnu.git] / bsd / miscfs / union / union.h

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This Original Code and all software distributed under the License are
 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
 * License for the specific language governing rights and limitations
 * under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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.
 * 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
 */

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

struct union_mount {
	struct vnode	*um_uppervp;
	struct vnode	*um_lowervp;
	struct ucred	*um_cred;	/* Credentials of user calling mount */
	int		um_cmode;	/* cmask from mount process */
	int		um_op;		/* Operation mode */
};

#ifdef KERNEL

/*
 * 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
 */
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_hash;	/* saved un_path hash value */
	int			un_openl;	/* # of opens on lowervp */
	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 */
#if DIAGNOSTIC
	pid_t			un_pid;
#endif
};

#define UN_WANT		0x01
#define UN_LOCKED	0x02
#define UN_ULOCK	0x04		/* Upper node is locked */
#define UN_KLOCK	0x08		/* Keep upper node locked on vput */
#define UN_CACHED	0x10		/* In union cache */

extern int union_allocvp __P((struct vnode **, struct mount *,
				struct vnode *, struct vnode *,
				struct componentname *, struct vnode *,
				struct vnode *, int));
extern int union_copyfile __P((struct vnode *, struct vnode *,
					struct ucred *, struct proc *));
extern int union_copyup __P((struct union_node *, int, struct ucred *,
				struct proc *));
extern int union_dowhiteout __P((struct union_node *, struct ucred *,
					struct proc *));
extern int union_mkshadow __P((struct union_mount *, struct vnode *,
				struct componentname *, struct vnode **));
extern int union_mkwhiteout __P((struct union_mount *, struct vnode *,
				struct componentname *, char *));
extern int union_vn_create __P((struct vnode **, struct union_node *,
				struct proc *));
extern int union_cn_close __P((struct vnode *, int, struct ucred *,
				struct proc *));
extern void union_removed_upper __P((struct union_node *un));
extern struct vnode *union_lowervp __P((struct vnode *));
extern void union_newlower __P((struct union_node *, struct vnode *));
extern void union_newupper __P((struct union_node *, struct vnode *));
extern void union_newsize __P((struct vnode *, off_t, off_t));

#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))

extern int (**union_vnodeop_p)(void *);
extern struct vfsops union_vfsops;
#endif /* KERNEL */
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
	11	*
	12	* This Original Code and all software distributed under the License are
	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
	23	/*
	24	* Copyright (c) 1994 The Regents of the University of California.
	25	* Copyright (c) 1994 Jan-Simon Pendry.
	26	* All rights reserved.
	27	*
	28	* This code is derived from software donated to Berkeley by
	29	* Jan-Simon Pendry.
	30	*
	31	* Redistribution and use in source and binary forms, with or without
	32	* modification, are permitted provided that the following conditions
	33	* are met:
	34	* 1. Redistributions of source code must retain the above copyright
	35	* notice, this list of conditions and the following disclaimer.
	36	* 2. Redistributions in binary form must reproduce the above copyright
	37	* notice, this list of conditions and the following disclaimer in the
	38	* documentation and/or other materials provided with the distribution.
	39	* 3. All advertising materials mentioning features or use of this software
	40	* must display the following acknowledgement:
	41	* This product includes software developed by the University of
	42	* California, Berkeley and its contributors.
	43	* 4. Neither the name of the University nor the names of its contributors
	44	* may be used to endorse or promote products derived from this software
	45	* without specific prior written permission.
	46	*
	47	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	48	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	49	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	50	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	51	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	52	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	53	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	54	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	55	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	56	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	57	* SUCH DAMAGE.
	58	*
	59	* @(#)union.h 8.9 (Berkeley) 12/10/94
	60	*/
	61
	62	struct union_args {
	63	char target; / Target of loopback */
	64	int mntflags; /* Options on the mount */
65	};
66
67	#define UNMNT_ABOVE 0x0001 /* Target appears below mount point */
68	#define UNMNT_BELOW 0x0002 /* Target appears below mount point */
69	#define UNMNT_REPLACE 0x0003 /* Target replaces mount point */
70	#define UNMNT_OPMASK 0x0003
71
72	struct union_mount {
73	struct vnode *um_uppervp;
74	struct vnode *um_lowervp;
75	struct ucred um_cred; / Credentials of user calling mount */
76	int um_cmode; /* cmask from mount process */
77	int um_op; /* Operation mode */
78	};
79
80	#ifdef KERNEL
81
82	/*
83	* DEFDIRMODE is the mode bits used to create a shadow directory.
84	*/
85	#define VRWXMODE (VREAD\|VWRITE\|VEXEC)
86	#define VRWMODE (VREAD\|VWRITE)
87	#define UN_DIRMODE ((VRWXMODE)\|(VRWXMODE>>3)\|(VRWXMODE>>6))
88	#define UN_FILEMODE ((VRWMODE)\|(VRWMODE>>3)\|(VRWMODE>>6))
89
90	/*
91	* A cache of vnode references
92	*/
93	struct union_node {
94	LIST_ENTRY(union_node) un_cache; /* Hash chain */
95	struct vnode un_vnode; / Back pointer */
96	struct vnode un_uppervp; / overlaying object */
97	struct vnode un_lowervp; / underlying object */
98	struct vnode un_dirvp; / Parent dir of uppervp */
99	struct vnode un_pvp; / Parent vnode */
100	char un_path; / saved component name */
101	int un_hash; /* saved un_path hash value */
102	int un_openl; /* # of opens on lowervp */
103	unsigned int un_flags;
104	struct vnode *un_dircache; / cached union stack */
105	off_t un_uppersz; /* size of upper object */
106	off_t un_lowersz; /* size of lower object */
107	#if DIAGNOSTIC
108	pid_t un_pid;
109	#endif
110	};
111
112	#define UN_WANT 0x01
113	#define UN_LOCKED 0x02
114	#define UN_ULOCK 0x04 /* Upper node is locked */
115	#define UN_KLOCK 0x08 /* Keep upper node locked on vput */
116	#define UN_CACHED 0x10 /* In union cache */
117
118	extern int union_allocvp __P((struct vnode *, struct mount ,
119	struct vnode , struct vnode ,
120	struct componentname , struct vnode ,
121	struct vnode *, int));
122	extern int union_copyfile __P((struct vnode , struct vnode ,
123	struct ucred , struct proc ));
124	extern int union_copyup __P((struct union_node , int, struct ucred ,
125	struct proc *));
126	extern int union_dowhiteout __P((struct union_node , struct ucred ,
127	struct proc *));
128	extern int union_mkshadow __P((struct union_mount , struct vnode ,
129	struct componentname , struct vnode *));
130	extern int union_mkwhiteout __P((struct union_mount , struct vnode ,
131	struct componentname , char ));
132	extern int union_vn_create __P((struct vnode *, struct union_node ,
133	struct proc *));
134	extern int union_cn_close __P((struct vnode , int, struct ucred ,
135	struct proc *));
136	extern void union_removed_upper __P((struct union_node *un));
137	extern struct vnode union_lowervp __P((struct vnode ));
138	extern void union_newlower __P((struct union_node , struct vnode ));
139	extern void union_newupper __P((struct union_node , struct vnode ));
140	extern void union_newsize __P((struct vnode *, off_t, off_t));
141
142	#define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data))
143	#define VTOUNION(vp) ((struct union_node *)(vp)->v_data)
144	#define UNIONTOV(un) ((un)->un_vnode)
145	#define LOWERVP(vp) (VTOUNION(vp)->un_lowervp)
146	#define UPPERVP(vp) (VTOUNION(vp)->un_uppervp)
147	#define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp))
148
149	extern int (*union_vnodeop_p)(void );
150	extern struct vfsops union_vfsops;
151	#endif /* KERNEL */