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 8.2 (Berkeley) 02/17/94 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 int um_op; /* Operation mode */ 30 }; 31 32 #ifdef KERNEL 33 34 /* 35 * DEFDIRMODE is the mode bits used to create a shadow directory. 36 */ 37 #define VRWXMODE (VREAD|VWRITE|VEXEC) 38 #define VRWMODE (VREAD|VWRITE) 39 #define UN_DIRMODE ((VRWXMODE)|(VRWXMODE>>3)|(VRWXMODE>>6)) 40 #define UN_FILEMODE ((VRWMODE)|(VRWMODE>>3)|(VRWMODE>>6)) 41 42 /* 43 * A cache of vnode references 44 */ 45 struct union_node { 46 LIST_ENTRY(union_node) un_cache; /* Hash chain */ 47 struct vnode *un_vnode; /* Back pointer */ 48 struct vnode *un_uppervp; /* overlaying object */ 49 struct vnode *un_lowervp; /* underlying object */ 50 struct vnode *un_dirvp; /* Parent dir of uppervp */ 51 char *un_path; /* saved component name */ 52 int un_hash; /* saved un_path hash value */ 53 int un_openl; /* # of opens on lowervp */ 54 int un_flags; 55 #ifdef DIAGNOSTIC 56 pid_t un_pid; 57 #endif 58 }; 59 60 #define UN_WANT 0x01 61 #define UN_LOCKED 0x02 62 #define UN_ULOCK 0x04 /* Upper node is locked */ 63 #define UN_KLOCK 0x08 /* Keep upper node locked on vput */ 64 65 extern int union_allocvp __P((struct vnode **, struct mount *, 66 struct vnode *, struct vnode *, 67 struct componentname *, struct vnode *, 68 struct vnode *)); 69 extern int union_copyfile __P((struct proc *, struct ucred *, 70 struct vnode *, struct vnode *)); 71 extern int union_mkshadow __P((struct union_mount *, struct vnode *, 72 struct componentname *, struct vnode **)); 73 extern int union_vn_create __P((struct vnode **, struct union_node *, 74 struct proc *)); 75 extern int union_cn_close __P((struct vnode *, int, struct ucred *, 76 struct proc *)); 77 extern void union_removed_upper __P((struct union_node *un)); 78 extern struct vnode *union_lowervp __P((struct vnode *)); 79 extern void union_newlower __P((struct union_node *, struct vnode *)); 80 extern void union_newupper __P((struct union_node *, struct vnode *)); 81 82 #define MOUNTTOUNIONMOUNT(mp) ((struct union_mount *)((mp)->mnt_data)) 83 #define VTOUNION(vp) ((struct union_node *)(vp)->v_data) 84 #define UNIONTOV(un) ((un)->un_vnode) 85 #define LOWERVP(vp) (VTOUNION(vp)->un_lowervp) 86 #define UPPERVP(vp) (VTOUNION(vp)->un_uppervp) 87 #define OTHERVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : LOWERVP(vp)) 88 89 extern int (**union_vnodeop_p)(); 90 extern struct vfsops union_vfsops; 91 #endif /* KERNEL */ 92