union.h revision 7090
11541Srgrimes/* 21541Srgrimes * Copyright (c) 1994 The Regents of the University of California. 31541Srgrimes * Copyright (c) 1994 Jan-Simon Pendry. 41541Srgrimes * All rights reserved. 51541Srgrimes * 61541Srgrimes * This code is derived from software donated to Berkeley by 71541Srgrimes * Jan-Simon Pendry. 81541Srgrimes * 91541Srgrimes * Redistribution and use in source and binary forms, with or without 101541Srgrimes * modification, are permitted provided that the following conditions 111541Srgrimes * are met: 121541Srgrimes * 1. Redistributions of source code must retain the above copyright 131541Srgrimes * notice, this list of conditions and the following disclaimer. 141541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 151541Srgrimes * notice, this list of conditions and the following disclaimer in the 161541Srgrimes * documentation and/or other materials provided with the distribution. 171541Srgrimes * 3. All advertising materials mentioning features or use of this software 181541Srgrimes * must display the following acknowledgement: 191541Srgrimes * This product includes software developed by the University of 201541Srgrimes * California, Berkeley and its contributors. 211541Srgrimes * 4. Neither the name of the University nor the names of its contributors 221541Srgrimes * may be used to endorse or promote products derived from this software 231541Srgrimes * without specific prior written permission. 241541Srgrimes * 251541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 261541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 271541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 281541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 291541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 301541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 311541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 321541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 331541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 341541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 351541Srgrimes * SUCH DAMAGE. 361541Srgrimes * 371541Srgrimes * @(#)union.h 8.2 (Berkeley) 2/17/94 387090Sbde * $Id: union.h,v 1.2 1994/08/02 07:45:42 davidg Exp $ 391541Srgrimes */ 401541Srgrimes 411541Srgrimesstruct union_args { 421541Srgrimes char *target; /* Target of loopback */ 431541Srgrimes int mntflags; /* Options on the mount */ 441541Srgrimes}; 451541Srgrimes 461541Srgrimes#define UNMNT_ABOVE 0x0001 /* Target appears below mount point */ 471541Srgrimes#define UNMNT_BELOW 0x0002 /* Target appears below mount point */ 481541Srgrimes#define UNMNT_REPLACE 0x0003 /* Target replaces mount point */ 491541Srgrimes#define UNMNT_OPMASK 0x0003 501541Srgrimes 511541Srgrimesstruct union_mount { 521541Srgrimes struct vnode *um_uppervp; 531541Srgrimes struct vnode *um_lowervp; 541541Srgrimes struct ucred *um_cred; /* Credentials of user calling mount */ 551541Srgrimes int um_cmode; /* cmask from mount process */ 561541Srgrimes int um_op; /* Operation mode */ 571541Srgrimes}; 581541Srgrimes 591541Srgrimes#ifdef KERNEL 601541Srgrimes 611541Srgrimes/* 621541Srgrimes * DEFDIRMODE is the mode bits used to create a shadow directory. 631541Srgrimes */ 641541Srgrimes#define VRWXMODE (VREAD|VWRITE|VEXEC) 651541Srgrimes#define VRWMODE (VREAD|VWRITE) 661541Srgrimes#define UN_DIRMODE ((VRWXMODE)|(VRWXMODE>>3)|(VRWXMODE>>6)) 671541Srgrimes#define UN_FILEMODE ((VRWMODE)|(VRWMODE>>3)|(VRWMODE>>6)) 681541Srgrimes 691541Srgrimes/* 701541Srgrimes * A cache of vnode references 711541Srgrimes */ 721541Srgrimesstruct union_node { 731541Srgrimes LIST_ENTRY(union_node) un_cache; /* Hash chain */ 741541Srgrimes struct vnode *un_vnode; /* Back pointer */ 751541Srgrimes struct vnode *un_uppervp; /* overlaying object */ 761541Srgrimes struct vnode *un_lowervp; /* underlying object */ 771541Srgrimes struct vnode *un_dirvp; /* Parent dir of uppervp */ 781541Srgrimes char *un_path; /* saved component name */ 791541Srgrimes int un_hash; /* saved un_path hash value */ 801541Srgrimes int un_openl; /* # of opens on lowervp */ 811541Srgrimes int un_flags; 821541Srgrimes#ifdef DIAGNOSTIC 831541Srgrimes pid_t un_pid; 841541Srgrimes#endif 851541Srgrimes}; 861541Srgrimes 871541Srgrimes#define UN_WANT 0x01 881541Srgrimes#define UN_LOCKED 0x02 891541Srgrimes#define UN_ULOCK 0x04 /* Upper node is locked */ 901541Srgrimes#define UN_KLOCK 0x08 /* Keep upper node locked on vput */ 911541Srgrimes 921541Srgrimesextern int union_allocvp __P((struct vnode **, struct mount *, 931541Srgrimes struct vnode *, struct vnode *, 941541Srgrimes struct componentname *, struct vnode *, 951541Srgrimes struct vnode *)); 967090Sbdeextern int union_freevp __P((struct vnode *)); 971541Srgrimesextern int union_copyfile __P((struct proc *, struct ucred *, 981541Srgrimes struct vnode *, struct vnode *)); 991541Srgrimesextern int union_mkshadow __P((struct union_mount *, struct vnode *, 1001541Srgrimes struct componentname *, struct vnode **)); 1011541Srgrimesextern int union_vn_create __P((struct vnode **, struct union_node *, 1021541Srgrimes struct proc *)); 1037090Sbdeextern int union_vn_close __P((struct vnode *, int, struct ucred *, 1047090Sbde struct proc *)); 1051541Srgrimesextern int union_cn_close __P((struct vnode *, int, struct ucred *, 1061541Srgrimes struct proc *)); 1071541Srgrimesextern void union_removed_upper __P((struct union_node *un)); 1081541Srgrimesextern struct vnode *union_lowervp __P((struct vnode *)); 1091541Srgrimesextern void union_newlower __P((struct union_node *, struct vnode *)); 1101541Srgrimesextern void union_newupper __P((struct union_node *, struct vnode *)); 1111541Srgrimes 1121541Srgrimes#define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data)) 1131541Srgrimes#define VTOUNION(vp) ((struct union_node *)(vp)->v_data) 1141541Srgrimes#define UNIONTOV(un) ((un)->un_vnode) 1151541Srgrimes#define LOWERVP(vp) (VTOUNION(vp)->un_lowervp) 1161541Srgrimes#define UPPERVP(vp) (VTOUNION(vp)->un_uppervp) 1171541Srgrimes#define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp)) 1181541Srgrimes 1191541Srgrimesextern int (**union_vnodeop_p)(); 1201541Srgrimesextern struct vfsops union_vfsops; 1211541Srgrimes#endif /* KERNEL */ 122