1 /* 2 * Copyright (c) 1994 The Regents of the University of California. 3 * Copyright (c) 1994 Jan-Simon Pendry. 4 * All rights reserved. 5 * 6 * This code is derived from software donated to Berkeley by 7 * Jan-Simon Pendry. 8 * 9 * %sccs.include.redist.c% 10 * 11 * @(#)union.h 1.9 (Berkeley) 02/08/94 12 */ 13 14 struct union_args { 15 char *target; /* Target of loopback */ 16 int mntflags; /* Options on the mount */ 17 }; 18 19 #define UNMNT_ABOVE 0x0001 /* Target appears below mount point */ 20 #define UNMNT_BELOW 0x0002 /* Target appears below mount point */ 21 #define UNMNT_REPLACE 0x0003 /* Target replaces mount point */ 22 #define UNMNT_OPMASK 0x0003 23 24 struct union_mount { 25 struct vnode *um_uppervp; 26 struct vnode *um_lowervp; 27 struct ucred *um_cred; /* Credentials of user calling mount */ 28 int um_cmode; /* cmask from mount process */ 29 }; 30 31 #ifdef KERNEL 32 33 /* 34 * DEFDIRMODE is the mode bits used to create a shadow directory. 35 */ 36 #define VRWXMODE (VREAD|VWRITE|VEXEC) 37 #define VRWMODE (VREAD|VWRITE) 38 #define UN_DIRMODE ((VRWXMODE)|(VRWXMODE>>3)|(VRWXMODE>>6)) 39 #define UN_FILEMODE ((VRWMODE)|(VRWMODE>>3)|(VRWMODE>>6)) 40 41 /* 42 * A cache of vnode references 43 */ 44 struct union_node { 45 struct union_node *un_next; /* Hash chain */ 46 struct vnode *un_vnode; /* Back pointer */ 47 struct vnode *un_uppervp; /* overlaying object */ 48 struct vnode *un_lowervp; /* underlying object */ 49 struct vnode *un_dirvp; /* Parent dir of uppervp */ 50 char *un_path; /* saved component name */ 51 int un_hash; /* saved un_path hash value */ 52 int un_openl; /* # of opens on lowervp */ 53 int un_flags; 54 #ifdef DIAGNOSTIC 55 pid_t un_pid; 56 #endif 57 }; 58 59 #define UN_WANT 0x01 60 #define UN_LOCKED 0x02 61 62 extern int union_allocvp __P((struct vnode **, struct mount *, 63 struct vnode *, struct vnode *, 64 struct componentname *, struct vnode *, 65 struct vnode *)); 66 extern int union_copyfile __P((struct proc *, struct ucred *, 67 struct vnode *, struct vnode *)); 68 extern int union_mkshadow __P((struct union_mount *, struct vnode *, 69 struct componentname *, struct vnode **)); 70 extern int union_vn_create __P((struct vnode **, struct union_node *, 71 struct proc *)); 72 extern int union_cn_close __P((struct vnode *, int, struct ucred *, 73 struct proc *)); 74 extern void union_removed_upper __P((struct union_node *un)); 75 extern struct vnode *union_lowervp __P((struct vnode *)); 76 77 #define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data)) 78 #define VTOUNION(vp) ((struct union_node *)(vp)->v_data) 79 #define UNIONTOV(un) ((un)->un_vnode) 80 #define LOWERVP(vp) (VTOUNION(vp)->un_lowervp) 81 #define UPPERVP(vp) (VTOUNION(vp)->un_uppervp) 82 #define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp)) 83 84 extern int (**union_vnodeop_p)(); 85 extern struct vfsops union_vfsops; 86 #endif /* KERNEL */ 87