union.h revision 1.6
1 /* $NetBSD: union.h,v 1.6 2003/06/29 18:43:27 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1994 The Regents of the University of California. 5 * Copyright (c) 1994 Jan-Simon Pendry. 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 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Berkeley and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#)union.h 8.9 (Berkeley) 12/10/94 40 */ 41 42 struct union_args { 43 char *target; /* Target of loopback */ 44 int mntflags; /* Options on the mount */ 45 }; 46 47 #define UNMNT_ABOVE 0x0001 /* Target appears below mount point */ 48 #define UNMNT_BELOW 0x0002 /* Target appears below mount point */ 49 #define UNMNT_REPLACE 0x0003 /* Target replaces mount point */ 50 #define UNMNT_OPMASK 0x0003 51 52 #define UNMNT_BITS "\177\20" \ 53 "b\00above\0b\01below\0b\02replace" 54 55 struct union_mount { 56 struct vnode *um_uppervp; 57 struct vnode *um_lowervp; 58 struct ucred *um_cred; /* Credentials of user calling mount */ 59 int um_cmode; /* cmask from mount process */ 60 int um_op; /* Operation mode */ 61 }; 62 63 #ifdef _KERNEL 64 65 /* 66 * DEFDIRMODE is the mode bits used to create a shadow directory. 67 */ 68 #define UN_DIRMODE (S_IRWXU|S_IRWXG|S_IRWXO) 69 #define UN_FILEMODE (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH) 70 71 /* 72 * A cache of vnode references 73 */ 74 struct union_node { 75 LIST_ENTRY(union_node) un_cache; /* Hash chain */ 76 struct vnode *un_vnode; /* Back pointer */ 77 struct vnode *un_uppervp; /* overlaying object */ 78 struct vnode *un_lowervp; /* underlying object */ 79 struct vnode *un_dirvp; /* Parent dir of uppervp */ 80 struct vnode *un_pvp; /* Parent vnode */ 81 char *un_path; /* saved component name */ 82 int un_hash; /* saved un_path hash value */ 83 int un_openl; /* # of opens on lowervp */ 84 unsigned int un_flags; 85 struct vnode **un_dircache; /* cached union stack */ 86 off_t un_uppersz; /* size of upper object */ 87 off_t un_lowersz; /* size of lower object */ 88 #ifdef DIAGNOSTIC 89 pid_t un_pid; 90 #endif 91 }; 92 93 #define UN_WANTED 0x01 94 #define UN_LOCKED 0x02 95 #define UN_ULOCK 0x04 /* Upper node is locked */ 96 #define UN_KLOCK 0x08 /* Keep upper node locked on vput */ 97 #define UN_CACHED 0x10 /* In union cache */ 98 #define UN_DRAINING 0x20 /* upper node lock is draining */ 99 #define UN_DRAINED 0x40 /* upper node lock is drained */ 100 101 extern int union_allocvp __P((struct vnode **, struct mount *, 102 struct vnode *, struct vnode *, 103 struct componentname *, struct vnode *, 104 struct vnode *, int)); 105 extern int union_copyfile __P((struct vnode *, struct vnode *, 106 struct ucred *, struct lwp *)); 107 extern int union_copyup __P((struct union_node *, int, struct ucred *, 108 struct lwp *)); 109 extern void union_diruncache __P((struct union_node *)); 110 extern int union_dowhiteout __P((struct union_node *, struct ucred *, 111 struct lwp *)); 112 extern int union_mkshadow __P((struct union_mount *, struct vnode *, 113 struct componentname *, struct vnode **)); 114 extern int union_mkwhiteout __P((struct union_mount *, struct vnode *, 115 struct componentname *, char *)); 116 extern int union_vn_create __P((struct vnode **, struct union_node *, 117 struct lwp *)); 118 extern int union_cn_close __P((struct vnode *, int, struct ucred *, 119 struct lwp *)); 120 extern void union_removed_upper __P((struct union_node *un)); 121 extern struct vnode *union_lowervp __P((struct vnode *)); 122 extern void union_newlower __P((struct union_node *, struct vnode *)); 123 extern void union_newupper __P((struct union_node *, struct vnode *)); 124 extern void union_newsize __P((struct vnode *, off_t, off_t)); 125 int union_readdirhook(struct vnode **, struct file *, struct lwp *); 126 127 #define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data)) 128 #define VTOUNION(vp) ((struct union_node *)(vp)->v_data) 129 #define UNIONTOV(un) ((un)->un_vnode) 130 #define LOWERVP(vp) (VTOUNION(vp)->un_lowervp) 131 #define UPPERVP(vp) (VTOUNION(vp)->un_uppervp) 132 #define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp)) 133 134 extern int (**union_vnodeop_p) __P((void *)); 135 136 void union_init __P((void)); 137 void union_done __P((void)); 138 int union_freevp __P((struct vnode *)); 139 140 #endif /* _KERNEL */ 141
Indexes created Fri Sep 26 08:10:20 GMT 2025