/* $NetBSD: union.h,v 1.28 2015/02/16 10:22:00 hannken Exp $ */ /* * Copyright (c) 1994 The Regents of the University of California. * 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. 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 */ /* * 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 */ #ifndef _MISCFS_UNION_H_ #define _MISCFS_UNION_H_ 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 #define UNMNT_BITS "\177\20" \ "b\00above\0b\01below\0b\02replace\0" #ifdef _KERNEL struct union_mount { struct vnode *um_uppervp; struct vnode *um_lowervp; kauth_cred_t um_cred; /* Credentials of user calling mount */ int um_cmode; /* cmask from mount process */ int um_op; /* Operation mode */ }; /* * DEFDIRMODE is the mode bits used to create a shadow directory. */ #define UN_DIRMODE (S_IRWXU|S_IRWXG|S_IRWXO) #define UN_FILEMODE (S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH) /* * A cache of vnode references. * Lock requirements are: * * : stable * c unheadlock[hash] * l un_lock * m un_lock or vnode lock to read, un_lock and * exclusive vnode lock to write * v vnode lock to read, exclusive vnode lock to write * * Lock order is vnode then un_lock. */ struct union_node { kmutex_t un_lock; LIST_ENTRY(union_node) un_cache; /* c: Hash chain */ int un_refs; /* c: Reference counter */ struct mount *un_mount; /* c: union mount */ struct vnode *un_vnode; /* :: Back pointer */ struct vnode *un_uppervp; /* m: overlaying object */ struct vnode *un_lowervp; /* v: underlying object */ struct vnode *un_dirvp; /* v: Parent dir of uppervp */ struct vnode *un_pvp; /* v: Parent vnode */ char *un_path; /* v: saved component name */ int un_openl; /* v: # of opens on lowervp */ unsigned int un_cflags; /* c: cache flags */ struct vnode **un_dircache; /* v: cached union stack */ off_t un_uppersz; /* l: size of upper object */ off_t un_lowersz; /* l: size of lower object */ }; #define UN_CACHED 0x10 /* In union cache */ extern int union_allocvp(struct vnode **, struct mount *, struct vnode *, struct vnode *, struct componentname *, struct vnode *, struct vnode *, int); extern int union_check_rmdir(struct union_node *, kauth_cred_t); extern int union_copyfile(struct vnode *, struct vnode *, kauth_cred_t, struct lwp *); extern int union_copyup(struct union_node *, int, kauth_cred_t, struct lwp *); extern void union_diruncache(struct union_node *); extern int union_dowhiteout(struct union_node *, kauth_cred_t); extern int union_mkshadow(struct union_mount *, struct vnode *, struct componentname *, struct vnode **); extern int union_mkwhiteout(struct union_mount *, struct vnode *, struct componentname *, struct union_node *); extern int union_vn_create(struct vnode **, struct union_node *, struct lwp *); extern int union_cn_close(struct vnode *, int, kauth_cred_t, struct lwp *); extern void union_removed_upper(struct union_node *un); extern struct vnode *union_lowervp(struct vnode *); extern void union_newlower(struct union_node *, struct vnode *); extern void union_newupper(struct union_node *, struct vnode *); extern void union_newsize(struct vnode *, off_t, off_t); int union_readdirhook(struct vnode **, struct file *, struct lwp *); VFS_PROTOS(union); #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)) #define LOCKVP(vp) (UPPERVP(vp) ? UPPERVP(vp) : (vp)) extern int (**union_vnodeop_p)(void *); void union_init(void); void union_reinit(void); void union_done(void); int union_freevp(struct vnode *); #endif /* _KERNEL */ #endif /* _MISCFS_UNION_H_ */