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Diffstat (limited to 'sys/miscfs/genfs/layer.h')
| -rw-r--r-- | sys/miscfs/genfs/layer.h | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/sys/miscfs/genfs/layer.h b/sys/miscfs/genfs/layer.h new file mode 100644 index 00000000000..c2e4451c16e --- /dev/null +++ b/sys/miscfs/genfs/layer.h @@ -0,0 +1,167 @@ +/* $OpenBSD: layer.h,v 1.1 2003/05/12 20:58:40 tedu Exp $ */ +/* $NetBSD: layer.h,v 1.4 2001/06/07 13:32:46 wiz Exp $ */ + +/* + * Copyright (c) 1999 National Aeronautics & Space Administration + * All rights reserved. + * + * This software was written by William Studenmund of the + * Numerical Aerospace Simulation Facility, NASA Ames Research Center. + * + * 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 National Aeronautics & Space Administration + * 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 NATIONAL AERONAUTICS & SPACE ADMINISTRATION + * ``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 ADMINISTRATION OR CONTRIB- + * UTORS 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. + */ + +/* + * Copyright (c) 1992, 1993 + * 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. 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. + * + * from: Id: lofs.h,v 1.8 1992/05/30 10:05:43 jsp Exp + * @(#)null.h 8.2 (Berkeley) 1/21/94 + */ + +#ifndef _MISCFS_GENFS_LAYER_H_ +#define _MISCFS_GENFS_LAYER_H_ + +struct layer_args { + char *target; /* Target of loopback */ + struct export_args export; /* network export info */ +}; + +#ifdef _KERNEL + +struct layer_node; + +LIST_HEAD(layer_node_hashhead, layer_node); + +struct layer_mount { + struct mount *layerm_vfs; + struct vnode *layerm_rootvp; /* Ref to root layer_node */ + struct netexport layerm_export; /* export info */ + u_int layerm_flags; /* mount point layer flags */ + u_int layerm_size; /* size of fs's struct node */ + enum vtype layerm_tag; /* vtag of our vnodes */ + int /* bypass routine for this mount */ + (*layerm_bypass)(void *); + int (*layerm_alloc) /* alloc a new layer node */ + (struct mount *, struct vnode *, + struct vnode **); + int /* ops for our nodes */ + (**layerm_vnodeop_p)(void *); + struct layer_node_hashhead /* head of hash list for layer_nodes */ + *layerm_node_hashtbl; + u_long layerm_node_hash; /* hash mask for hash chain */ + struct simplelock layerm_hashlock; /* interlock for hash chain. */ +}; + +#define LAYERFS_MFLAGS 0x00000fff /* reserved layer mount flags */ +#define LAYERFS_MBYPASSDEBUG 0x00000001 + +/* + * A cache of vnode references + */ +struct layer_node { + LIST_ENTRY(layer_node) layer_hash; /* Hash list */ + struct vnode *layer_lowervp; /* VREFed once */ + struct vnode *layer_vnode; /* Back pointer */ + unsigned int layer_flags; /* locking, etc. */ +}; + +#define LAYERFS_RESFLAGS 0x00000fff /* flags reserved for layerfs */ + +/* + * The following macros handle upperfs-specific locking. They are needed + * when the lowerfs does not export a struct lock for locking use by the + * upper layers. These macros are inteded for adjusting the upperfs + * struct lock to reflect changes in the underlying vnode's lock state. + */ +#define LAYERFS_UPPERLOCK(v, f, r) do { \ + if ((v)->v_vnlock == NULL) \ + r = lockmgr(&(v)->v_lock, (f), &(v)->v_interlock, curproc); \ + else \ + r = 0; \ + } while (0) + +#define LAYERFS_UPPERUNLOCK(v, f, r) do { \ + if ((v)->v_vnlock == NULL) \ + r = lockmgr(&(v)->v_lock, (f) | LK_RELEASE, &(v)->v_interlock, curproc); \ + else \ + r = 0; \ + } while (0) + +#define LAYERFS_UPPERISLOCKED(v, r) do { \ + if ((v)->v_vnlock == NULL) \ + r = lockstatus(&(v)->v_lock); \ + else \ + r = -1; \ + } while (0) + +#define LAYERFS_DO_BYPASS(vp, ap) \ + (*MOUNTTOLAYERMOUNT((vp)->v_mount)->layerm_bypass)((ap)) + +extern struct vnode *layer_checkvp(struct vnode *vp, char *fil, int lno); + +#define MOUNTTOLAYERMOUNT(mp) ((struct layer_mount *)((mp)->mnt_data)) +#define VTOLAYER(vp) ((struct layer_node *)(vp)->v_data) +#define LAYERTOV(xp) ((xp)->layer_vnode) +#ifdef LAYERFS_DIAGNOSTIC +#define LAYERVPTOLOWERVP(vp) layer_checkvp((vp), __FILE__, __LINE__) +#else +#define LAYERVPTOLOWERVP(vp) (VTOLAYER(vp)->layer_lowervp) +#endif + +#endif /* _KERNEL */ +#endif /* _MISCFS_GENFS_LAYER_H_ */ |