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Diffstat (limited to 'sys/fs/unionfs/union.h')
-rw-r--r-- | sys/fs/unionfs/union.h | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/sys/fs/unionfs/union.h b/sys/fs/unionfs/union.h new file mode 100644 index 0000000..3fb0b6e --- /dev/null +++ b/sys/fs/unionfs/union.h @@ -0,0 +1,155 @@ +/* + * Copyright (c) 1994 The Regents of the University of California. + * 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 + * $FreeBSD$ + */ + +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 + +struct union_mount { + struct vnode *um_uppervp; /* UN_ULOCK holds locking state */ + struct vnode *um_lowervp; /* Left unlocked */ + struct ucred *um_cred; /* Credentials of user calling mount */ + int um_cmode; /* cmask from mount process */ + int um_op; /* Operation mode */ +}; + +#ifdef KERNEL + +#ifndef DIAGNOSTIC +#define DIAGNOSTIC +#endif + +/* + * DEFDIRMODE is the mode bits used to create a shadow directory. + */ +#define VRWXMODE (VREAD|VWRITE|VEXEC) +#define VRWMODE (VREAD|VWRITE) +#define UN_DIRMODE ((VRWXMODE)|(VRWXMODE>>3)|(VRWXMODE>>6)) +#define UN_FILEMODE ((VRWMODE)|(VRWMODE>>3)|(VRWMODE>>6)) + +/* + * A cache of vnode references (hangs off v_data) + * + * Placing un_lock as the first elements theoretically allows us to + * use the vop_stdlock functions. However, we need to make sure of + * certain side effects so we will still punch in our own code. + */ +struct union_node { + struct lock un_lock; + LIST_ENTRY(union_node) un_cache; /* Hash chain */ + struct vnode *un_vnode; /* Back pointer */ + struct vnode *un_uppervp; /* overlaying object */ + struct vnode *un_lowervp; /* underlying object */ + struct vnode *un_dirvp; /* Parent dir of uppervp */ + struct vnode *un_pvp; /* Parent vnode */ + char *un_path; /* saved component name */ + int un_openl; /* # of opens on lowervp */ + int un_exclcnt; /* exclusive count */ + unsigned int un_flags; + struct vnode **un_dircache; /* cached union stack */ + off_t un_uppersz; /* size of upper object */ + off_t un_lowersz; /* size of lower object */ +#ifdef DIAGNOSTIC + pid_t un_pid; +#endif +}; + +/* + * XXX UN_ULOCK - indicates that the uppervp is locked + * + * UN_CACHED - node is in the union cache + */ + +/*#define UN_ULOCK 0x04*/ /* Upper node is locked */ +#define UN_CACHED 0x10 /* In union cache */ + +/* + * Hash table locking flags + */ + +#define UNVP_WANT 0x01 +#define UNVP_LOCKED 0x02 + +extern int union_allocvp __P((struct vnode **, struct mount *, + struct vnode *, + struct vnode *, + struct componentname *, struct vnode *, + struct vnode *, int)); +extern int union_freevp __P((struct vnode *)); +extern struct vnode *union_dircache __P((struct vnode *, struct proc *)); +extern int union_copyup __P((struct union_node *, int, struct ucred *, + struct proc *)); +extern int union_dowhiteout __P((struct union_node *, struct ucred *, + struct proc *)); +extern int union_mkshadow __P((struct union_mount *, struct vnode *, + struct componentname *, struct vnode **)); +extern int union_mkwhiteout __P((struct union_mount *, struct vnode *, + struct componentname *, char *)); +extern int union_cn_close __P((struct vnode *, int, struct ucred *, + struct proc *)); +extern void union_removed_upper __P((struct union_node *un)); +extern struct vnode *union_lowervp __P((struct vnode *)); +extern void union_newsize __P((struct vnode *, off_t, off_t)); +extern void union_vm_coherency __P((struct vnode *, struct uio *, int)); + +extern int (*union_dircheckp) __P((struct proc *, struct vnode **, + struct file *)); + +#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 UDEBUG(x) if (uniondebug) printf x +#define UDEBUG_ENABLED 1 + +extern vop_t **union_vnodeop_p; +extern struct vfsops union_vfsops; +extern int uniondebug; + +#endif /* KERNEL */ |