diff options
author | Ted Unangst <tedu@cvs.openbsd.org> | 2003-05-12 21:00:40 +0000 |
---|---|---|
committer | Ted Unangst <tedu@cvs.openbsd.org> | 2003-05-12 21:00:40 +0000 |
commit | 104c9cee2b7581512ef5cf06fb24402ea5fa56c5 (patch) | |
tree | 5fdd84bbcbd97d421bf48dc5260bc924bb1f0abb /sys/miscfs/nullfs | |
parent | a4037f6b4fd1ba42f6428bea41cfc9ff22c44528 (diff) |
most of the fixes for nullfs. use the new common layer stuff in genfs.
Diffstat (limited to 'sys/miscfs/nullfs')
-rw-r--r-- | sys/miscfs/nullfs/null.h | 81 | ||||
-rw-r--r-- | sys/miscfs/nullfs/null_vfsops.c | 364 | ||||
-rw-r--r-- | sys/miscfs/nullfs/null_vnops.c | 640 |
3 files changed, 267 insertions, 818 deletions
diff --git a/sys/miscfs/nullfs/null.h b/sys/miscfs/nullfs/null.h index 5b91a2f2ce9..b58e3040098 100644 --- a/sys/miscfs/nullfs/null.h +++ b/sys/miscfs/nullfs/null.h @@ -1,5 +1,38 @@ -/* $OpenBSD: null.h,v 1.11 2002/03/14 01:27:08 millert Exp $ */ -/* $NetBSD: null.h,v 1.7 1996/05/17 20:53:11 gwr Exp $ */ +/* $OpenBSD: null.h,v 1.12 2003/05/12 21:00:39 tedu Exp $ */ +/* $NetBSD: null.h,v 1.13 2001/11/07 04:56:09 enami 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 @@ -40,42 +73,58 @@ * @(#)null.h 8.2 (Berkeley) 1/21/94 */ +#include <miscfs/genfs/layer.h> + struct null_args { - char *target; /* Target of loopback */ + struct layer_args la; /* generic layerfs args */ }; +#define nulla_target la.target +#define nulla_export la.export +#ifdef _KERNEL struct null_mount { - struct mount *nullm_vfs; - struct vnode *nullm_rootvp; /* Reference to root null_node */ + struct layer_mount lm; /* generic layerfs mount stuff */ }; +#define nullm_vfs lm.layerm_vfs +#define nullm_rootvp lm.layerm_rootvp +#define nullm_export lm.layerm_export +#define nullm_flags lm.layerm_flags +#define nullm_size lm.layerm_size +#define nullm_tag lm.layerm_tag +#define nullm_bypass lm.layerm_bypass +#define nullm_alloc lm.layerm_alloc +#define nullm_vnodeop_p lm.layerm_vnodeop_p +#define nullm_node_hashtbl lm.layerm_node_hashtbl +#define nullm_node_hash lm.layerm_node_hash +#define nullm_hashlock lm.layerm_hashlock -#ifdef _KERNEL /* * A cache of vnode references */ struct null_node { - LIST_ENTRY(null_node) null_hash; /* Hash list */ - struct vnode *null_lowervp; /* VREFed once */ - struct vnode *null_vnode; /* Back pointer */ + struct layer_node ln; }; +#define null_hash ln.layer_hash +#define null_lowervp ln.layer_lowervp +#define null_vnode ln.layer_vnode +#define null_flags ln.layer_flags -extern int null_node_create(struct mount *mp, struct vnode *target, struct vnode **vpp, int lockit); +int null_node_create(struct mount *, struct vnode *, + struct vnode **, int); #define MOUNTTONULLMOUNT(mp) ((struct null_mount *)((mp)->mnt_data)) #define VTONULL(vp) ((struct null_node *)(vp)->v_data) #define NULLTOV(xp) ((xp)->null_vnode) #ifdef NULLFS_DIAGNOSTIC -extern struct vnode *null_checkvp(struct vnode *vp, char *fil, int lno); -#define NULLVPTOLOWERVP(vp) null_checkvp((vp), __FILE__, __LINE__) +struct vnode *layer_checkvp(struct vnode *, char *, int); +#define NULLVPTOLOWERVP(vp) layer_checkvp((vp), __FILE__, __LINE__) #else #define NULLVPTOLOWERVP(vp) (VTONULL(vp)->null_lowervp) #endif -extern int (**null_vnodeop_p)(void *); -extern struct vfsops null_vfsops; +extern int (**nullfs_vnodeop_p)(void *); +extern struct vfsops nullfs_vfsops; int nullfs_init(struct vfsconf *); -int null_bypass(void *); - #endif /* _KERNEL */ diff --git a/sys/miscfs/nullfs/null_vfsops.c b/sys/miscfs/nullfs/null_vfsops.c index a9f7d0f8ad0..8c3d37ac542 100644 --- a/sys/miscfs/nullfs/null_vfsops.c +++ b/sys/miscfs/nullfs/null_vfsops.c @@ -1,8 +1,40 @@ -/* $OpenBSD: null_vfsops.c,v 1.14 2003/02/24 22:32:46 tedu Exp $ */ -/* $NetBSD: null_vfsops.c,v 1.11 1996/05/10 22:50:56 jtk Exp $ */ +/* $OpenBSD: null_vfsops.c,v 1.15 2003/05/12 21:00:39 tedu Exp $ */ +/* $NetBSD: null_vfsops.c,v 1.38 2002/09/21 18:09:29 christos Exp $ */ /* - * Copyright (c) 1992, 1993 + * 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, 1995 * The Regents of the University of California. All rights reserved. * * This code is derived from software donated to Berkeley by @@ -38,7 +70,7 @@ * * from: Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp * from: @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92 - * @(#)null_vfsops.c 8.2 (Berkeley) 1/21/94 + * @(#)null_vfsops.c 8.7 (Berkeley) 5/14/95 */ /* @@ -46,29 +78,23 @@ * (See null_vnops.c for a description of what this does.) */ + #include <sys/param.h> #include <sys/systm.h> -#include <sys/proc.h> #include <sys/time.h> -#include <sys/types.h> +#include <sys/proc.h> #include <sys/vnode.h> #include <sys/mount.h> #include <sys/namei.h> #include <sys/malloc.h> + #include <miscfs/nullfs/null.h> +#include <miscfs/genfs/layer_extern.h> int nullfs_mount(struct mount *, const char *, void *, - struct nameidata *, struct proc *); -int nullfs_start(struct mount *, int, struct proc *); + struct nameidata *, struct proc *); int nullfs_unmount(struct mount *, int, struct proc *); -int nullfs_root(struct mount *, struct vnode **); -int nullfs_quotactl(struct mount *, int, uid_t, caddr_t, - struct proc *); -int nullfs_statfs(struct mount *, struct statfs *, struct proc *); -int nullfs_sync(struct mount *, int, struct ucred *, struct proc *); -int nullfs_vget(struct mount *, ino_t, struct vnode **); -int nullfs_fhtovp(struct mount *, struct fid *, struct vnode **); -int nullfs_vptofh(struct vnode *, struct fid *); + /* * Mount null layer */ @@ -80,37 +106,50 @@ nullfs_mount(mp, path, data, ndp, p) struct nameidata *ndp; struct proc *p; { - int error = 0; struct null_args args; struct vnode *lowerrootvp, *vp; - struct vnode *nullm_rootvp; - struct null_mount *xmp; + struct null_mount *nmp; + struct layer_mount *lmp; size_t size; + int error = 0; #ifdef NULLFS_DIAGNOSTIC printf("nullfs_mount(mp = %p)\n", mp); #endif - - /* - * Update is a no-op - */ - if (mp->mnt_flag & MNT_UPDATE) { - return (EOPNOTSUPP); - /* return VFS_MOUNT(MOUNTTONULLMOUNT(mp)->nullm_vfs, path, data, ndp, p);*/ +#if 0 + if (mp->mnt_flag & MNT_GETARGS) { + lmp = MOUNTTOLAYERMOUNT(mp); + if (lmp == NULL) + return EIO; + args.la.target = NULL; + vfs_showexport(mp, &args.la.export, &lmp->layerm_export); + return copyout(&args, data, sizeof(args)); } - +#endif /* * Get argument */ - error = copyin(data, &args, sizeof(struct null_args)); + error = copyin(data, (caddr_t)&args, sizeof(struct null_args)); if (error) return (error); /* + * Update only does export updating. + */ + if (mp->mnt_flag & MNT_UPDATE) { + lmp = MOUNTTOLAYERMOUNT(mp); + if (args.nulla_target == NULL) + return (vfs_export(mp, &lmp->layerm_export, + &args.la.export)); + else + return (EOPNOTSUPP); + } + + /* * Find lower node */ - NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF, - UIO_USERSPACE, args.target, p); + NDINIT(ndp, LOOKUP, FOLLOW|LOCKLEAF, + UIO_USERSPACE, args.la.target, p); if ((error = namei(ndp)) != 0) return (error); @@ -119,81 +158,70 @@ nullfs_mount(mp, path, data, ndp, p) */ lowerrootvp = ndp->ni_vp; - vrele(ndp->ni_dvp); - ndp->ni_dvp = NULL; - - if (lowerrootvp->v_type != VDIR) { - vput(lowerrootvp); - return (EINVAL); - } - - xmp = (struct null_mount *) malloc(sizeof(struct null_mount), - M_MISCFSMNT, M_WAITOK); - /* - * Save reference to underlying FS + * First cut at fixing up upper mount point */ - xmp->nullm_vfs = lowerrootvp->v_mount; + nmp = (struct null_mount *) malloc(sizeof(struct null_mount), + M_UFSMNT, M_WAITOK); /* XXX */ + memset((caddr_t)nmp, 0, sizeof(struct null_mount)); + + mp->mnt_data = (qaddr_t)nmp; + nmp->nullm_vfs = lowerrootvp->v_mount; + if (nmp->nullm_vfs->mnt_flag & MNT_LOCAL) + mp->mnt_flag |= MNT_LOCAL; /* - * Save reference. Each mount also holds - * a reference on the root vnode. + * Make sure that the mount point is sufficiently initialized + * that the node create call will work. */ - error = null_node_create(mp, lowerrootvp, &vp, 1); + vfs_getnewfsid(mp); + + nmp->nullm_size = sizeof(struct null_node); + nmp->nullm_tag = VT_NULL; + nmp->nullm_bypass = layer_bypass; + nmp->nullm_alloc = layer_node_alloc; /* the default alloc is fine */ + nmp->nullm_vnodeop_p = nullfs_vnodeop_p; + simple_lock_init(&nmp->nullm_hashlock); + nmp->nullm_node_hashtbl = hashinit(desiredvnodes, M_CACHE, + M_WAITOK, &nmp->nullm_node_hash); + /* - * Unlock the node (either the lower or the alias) + * Fix up null node for root vnode */ - VOP_UNLOCK(vp, 0, p); + error = layer_node_create(mp, lowerrootvp, &vp); /* - * Make sure the node alias worked + * Make sure the fixup worked */ if (error) { - vrele(lowerrootvp); - free(xmp, M_MISCFSMNT); + vput(lowerrootvp); + free(nmp->nullm_node_hashtbl, M_CACHE); return (error); } + /* + * Unlock the node + */ + VOP_UNLOCK(vp, 0, p); /* * Keep a held reference to the root vnode. * It is vrele'd in nullfs_unmount. */ - nullm_rootvp = vp; - nullm_rootvp->v_flag |= VROOT; - xmp->nullm_rootvp = nullm_rootvp; - if (NULLVPTOLOWERVP(nullm_rootvp)->v_mount->mnt_flag & MNT_LOCAL) - mp->mnt_flag |= MNT_LOCAL; - mp->mnt_data = (qaddr_t) xmp; - vfs_getnewfsid(mp); + vp->v_flag |= VROOT; + nmp->nullm_rootvp = vp; (void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size); - bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size); - (void) copyinstr(args.target, mp->mnt_stat.f_mntfromname, MNAMELEN - 1, - &size); - bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size); + memset(mp->mnt_stat.f_mntonname + size, 0, MNAMELEN - size); + (void) copyinstr(args.la.target, mp->mnt_stat.f_mntfromname, + MNAMELEN - 1, &size); + memset(mp->mnt_stat.f_mntfromname + size, 0, MNAMELEN - size); #ifdef NULLFS_DIAGNOSTIC printf("nullfs_mount: lower %s, alias at %s\n", - mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); + mp->mnt_stat.f_mntfromname, mp->mnt_stat.f_mntonname); #endif return (0); } /* - * VFS start. Nothing needed here - the start routine - * on the underlying filesystem will have been called - * when that filesystem was mounted. - */ -int -nullfs_start(mp, flags, p) - struct mount *mp; - int flags; - struct proc *p; -{ - - return (0); - /* return VFS_START(MOUNTTONULLMOUNT(mp)->nullm_vfs, flags, p); */ -} - -/* * Free reference to null layer */ int @@ -202,7 +230,8 @@ nullfs_unmount(mp, mntflags, p) int mntflags; struct proc *p; { - struct vnode *nullm_rootvp = MOUNTTONULLMOUNT(mp)->nullm_rootvp; + struct null_mount *nmp = MOUNTTONULLMOUNT(mp); + struct vnode *null_rootvp = nmp->nullm_rootvp; int error; int flags = 0; @@ -210,9 +239,8 @@ nullfs_unmount(mp, mntflags, p) printf("nullfs_unmount(mp = %p)\n", mp); #endif - if (mntflags & MNT_FORCE) { + if (mntflags & MNT_FORCE) flags |= FORCECLOSE; - } /* * Clear out buffer cache. I don't think we @@ -220,172 +248,56 @@ nullfs_unmount(mp, mntflags, p) * moment, but who knows... */ #if 0 - mntflushbuf(mp, 0); + mntflushbuf(mp, 0); if (mntinvalbuf(mp, 1)) return (EBUSY); #endif - if (nullm_rootvp->v_usecount > 1) + if (null_rootvp->v_usecount > 1) return (EBUSY); - if ((error = vflush(mp, nullm_rootvp, flags)) != 0) + if ((error = vflush(mp, null_rootvp, flags)) != 0) return (error); #ifdef NULLFS_DIAGNOSTIC - vprint("alias root of lower", nullm_rootvp); -#endif + vprint("alias root of lower", null_rootvp); +#endif /* * Release reference on underlying root vnode */ - vrele(nullm_rootvp); + vrele(null_rootvp); + /* * And blow it away for future re-use */ - vgone(nullm_rootvp); + vgone(null_rootvp); + /* * Finally, throw away the null_mount structure */ + free(nmp->nullm_node_hashtbl, M_CACHE); free(mp->mnt_data, M_MISCFSMNT); - mp->mnt_data = 0; + mp->mnt_data = NULL; return 0; } -int -nullfs_root(mp, vpp) - struct mount *mp; - struct vnode **vpp; -{ - struct vnode *vp; - struct proc *p = curproc; - -#ifdef NULLFS_DIAGNOSTIC - printf("nullfs_root(mp = %p, vp = %p->%p)\n", mp, - MOUNTTONULLMOUNT(mp)->nullm_rootvp, - NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp) - ); -#endif - - /* - * Return locked reference to root. - */ - vp = MOUNTTONULLMOUNT(mp)->nullm_rootvp; - VREF(vp); - vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, p); - *vpp = vp; - return 0; -} - -int -nullfs_quotactl(mp, cmd, uid, arg, p) - struct mount *mp; - int cmd; - uid_t uid; - caddr_t arg; - struct proc *p; -{ +extern const struct vnodeopv_desc nullfs_vnodeop_opv_desc; - return VFS_QUOTACTL(MOUNTTONULLMOUNT(mp)->nullm_vfs, cmd, uid, arg, p); -} - -int -nullfs_statfs(mp, sbp, p) - struct mount *mp; - struct statfs *sbp; - struct proc *p; -{ - int error; - struct statfs mstat; - -#ifdef NULLFS_DIAGNOSTIC - printf("nullfs_statfs(mp = %p, vp = %p->%p)\n", mp, - MOUNTTONULLMOUNT(mp)->nullm_rootvp, - NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp) - ); -#endif - - bzero(&mstat, sizeof(mstat)); - - error = VFS_STATFS(MOUNTTONULLMOUNT(mp)->nullm_vfs, &mstat, p); - if (error) - return (error); - - /* now copy across the "interesting" information and fake the rest */ - sbp->f_flags = mstat.f_flags; - sbp->f_bsize = mstat.f_bsize; - sbp->f_iosize = mstat.f_iosize; - sbp->f_blocks = mstat.f_blocks; - sbp->f_bfree = mstat.f_bfree; - sbp->f_bavail = mstat.f_bavail; - sbp->f_files = mstat.f_files; - sbp->f_ffree = mstat.f_ffree; - if (sbp != &mp->mnt_stat) { - bcopy(&mp->mnt_stat.f_fsid, &sbp->f_fsid, sizeof(sbp->f_fsid)); - bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN); - bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN); - } - strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN); - return (0); -} - -int -nullfs_sync(mp, waitfor, cred, p) - struct mount *mp; - int waitfor; - struct ucred *cred; - struct proc *p; -{ - - /* - * XXX - Assumes no data cached at null layer. - */ - return (0); -} - -int -nullfs_vget(mp, ino, vpp) - struct mount *mp; - ino_t ino; - struct vnode **vpp; -{ - - return VFS_VGET(MOUNTTONULLMOUNT(mp)->nullm_vfs, ino, vpp); -} - -int -nullfs_fhtovp(mp, fidp, vpp) - struct mount *mp; - struct fid *fidp; - struct vnode **vpp; -{ - - return (EOPNOTSUPP); -} - -int -nullfs_vptofh(vp, fhp) - struct vnode *vp; - struct fid *fhp; -{ - - return (EOPNOTSUPP); -} - -#define nullfs_sysctl ((int (*)(int *, u_int, void *, size_t *, void *, \ - size_t, struct proc *))eopnotsupp) - -#define nullfs_checkexp ((int (*)(struct mount *, struct mbuf *, \ - int *, struct ucred **))eopnotsupp) +const struct vnodeopv_desc * const nullfs_vnodeopv_descs[] = { + &nullfs_vnodeop_opv_desc, + NULL, +}; -struct vfsops null_vfsops = { +struct vfsops nullfs_vfsops = { nullfs_mount, - nullfs_start, + layerfs_start, nullfs_unmount, - nullfs_root, - nullfs_quotactl, - nullfs_statfs, - nullfs_sync, - nullfs_vget, - nullfs_fhtovp, - nullfs_vptofh, - nullfs_init, - nullfs_sysctl, - nullfs_checkexp + layerfs_root, + layerfs_quotactl, + layerfs_statfs, + layerfs_sync, + layerfs_vget, + layerfs_fhtovp, + layerfs_vptofh, + layerfs_init, + layerfs_sysctl, + layerfs_checkexp }; diff --git a/sys/miscfs/nullfs/null_vnops.c b/sys/miscfs/nullfs/null_vnops.c index 7df52de9f75..d8953a55ab9 100644 --- a/sys/miscfs/nullfs/null_vnops.c +++ b/sys/miscfs/nullfs/null_vnops.c @@ -1,7 +1,39 @@ -/* $OpenBSD: null_vnops.c,v 1.16 2002/10/27 15:27:18 brad Exp $ */ -/* $NetBSD: null_vnops.c,v 1.7 1996/05/10 22:51:01 jtk Exp $ */ +/* $OpenBSD: null_vnops.c,v 1.17 2003/05/12 21:00:39 tedu Exp $ */ +/* $NetBSD: null_vnops.c,v 1.26 2002/09/10 02:52:40 jtk 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. * @@ -36,602 +68,58 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * @(#)null_vnops.c 8.1 (Berkeley) 6/10/93 + * @(#)null_vnops.c 8.6 (Berkeley) 5/27/95 * * Ancestors: * @(#)lofs_vnops.c 1.2 (Berkeley) 6/18/92 - * Id: lofs_vnops.c,v 1.11 1992/05/30 10:05:43 jsp Exp + * Id: lofs_vnops.c,v 1.11 1992/05/30 10:05:43 jsp Exp jsp * ...and... * @(#)null_vnodeops.c 1.20 92/07/07 UCLA Ficus project */ /* - * Null Layer - * - * (See mount_null(8) for more information.) - * - * The null layer duplicates a portion of the file system - * name space under a new name. In this respect, it is - * similar to the loopback file system. It differs from - * the loopback fs in two respects: it is implemented using - * a stackable layers techniques, and its "null-node"s stack above - * all lower-layer vnodes, not just over directory vnodes. - * - * The null layer has two purposes. First, it serves as a demonstration - * of layering by providing a layer which does nothing. (It actually - * does everything the loopback file system does, which is slightly - * more than nothing.) Second, the null layer can serve as a prototype - * layer. Since it provides all necessary layer framework, - * new file system layers can be created very easily by starting - * with a null layer. - * - * The remainder of this man page examines the null layer as a basis - * for constructing new layers. - * - * - * INSTANTIATING NEW NULL LAYERS - * - * New null layers are created with mount_null(8). - * Mount_null(8) takes two arguments, the pathname - * of the lower vfs (target-pn) and the pathname where the null - * layer will appear in the namespace (alias-pn). After - * the null layer is put into place, the contents - * of target-pn subtree will be aliased under alias-pn. - * - * - * OPERATION OF A NULL LAYER - * - * The null layer is the minimum file system layer, - * simply bypassing all possible operations to the lower layer - * for processing there. The majority of its activity centers - * on the bypass routine, though which nearly all vnode operations - * pass. - * - * The bypass routine accepts arbitrary vnode operations for - * handling by the lower layer. It begins by examining vnode - * operation arguments and replacing any null-nodes by their - * lower-layer equivalents. It then invokes the operation - * on the lower layer. Finally, it replaces the null-nodes - * in the arguments and, if a vnode is returned by the operation, - * stacks a null-node on top of the returned vnode. - * - * Although bypass handles most operations, - * vop_getattr, _inactive, _reclaim, and _print are not bypassed. - * Vop_getattr must change the fsid being returned. - * Vop_lock and vop_unlock must handle any locking for the - * current vnode as well as pass the lock request down. - * Vop_inactive and vop_reclaim are not bypassed so that - * they can handle freeing null-layer specific data. Vop_print - * is not bypassed to avoid excessive debugging information. - * Also, certain vnode operations change the locking state within - * the operation (create, mknod, remove, link, rename, mkdir, rmdir, - * and symlink). Ideally, these operations should not change the - * lock state, but should be changed to let the caller of the - * function unlock them. Otherwise all intermediate vnode layers - * (such as union, umapfs, etc) must catch these functions - * to the necessary locking at their layer - * - * - * INSTANTIATING VNODE STACKS - * - * Mounting associates the null layer with a lower layer, - * in effect stacking two VFSes. Vnode stacks are instead - * created on demand as files are accessed. - * - * The initial mount creates a single vnode stack for the - * root of the new null layer. All other vnode stacks - * are created as a result of vnode operations on - * this or other null vnode stacks. - * - * New vnode stacks come into existence as a result of - * an operation which returns a vnode. - * The bypass routine stacks a null-node above the new - * vnode before returning it to the caller. - * - * For example, imagine mounting a null layer with - * "mount_null /usr/include /dev/layer/null". - * Changing directory to /dev/layer/null will assign - * the root null-node (which was created when the null layer was mounted). - * Now consider opening "sys". A vop_lookup would be - * done on the root null-node. This operation would bypass through - * to the lower layer which would return a vnode representing - * the UFS "sys". Null_bypass then builds a null-node - * aliasing the UFS "sys" and returns this to the caller. - * Later operations on the null-node "sys" will repeat this - * process when constructing other vnode stacks. - * - * - * CREATING OTHER FILE SYSTEM LAYERS - * - * One of the easiest ways to construct new file system layers is to make - * a copy of the null layer, rename all files and variables, and - * then begin modifing the copy. sed(1) can be used to easily rename - * all variables. - * - * The umap layer is an example of a layer descended from the - * null layer. - * - * - * INVOKING OPERATIONS ON LOWER LAYERS - * - * There are two techniques to invoke operations on a lower layer - * when the operation cannot be completely bypassed. Each method - * is appropriate in different situations. In both cases, - * it is the responsibility of the aliasing layer to make - * the operation arguments "correct" for the lower layer - * by mapping an vnode arguments to the lower layer. - * - * The first approach is to call the aliasing layer's bypass routine. - * This method is most suitable when you wish to invoke the operation - * currently being handled on the lower layer. It has the advantage - * that the bypass routine already must do argument mapping. - * An example of this is null_getattrs in the null layer. - * - * A second approach is to directly invoke vnode operations on - * the lower layer with the VOP_OPERATIONNAME interface. - * The advantage of this method is that it is easy to invoke - * arbitrary operations on the lower layer. The disadvantage - * is that vnode arguments must be manually mapped. - * + * See miscfs/genfs/layer_vnops.c and mount_null(8) for a + * description of the null file system. */ #include <sys/param.h> #include <sys/systm.h> #include <sys/proc.h> #include <sys/time.h> -#include <sys/types.h> #include <sys/vnode.h> #include <sys/mount.h> #include <sys/namei.h> #include <sys/malloc.h> #include <sys/buf.h> #include <miscfs/nullfs/null.h> - - -int null_bug_bypass = 0; /* for debugging: enables bypass printf'ing */ - -int null_getattr(void *); -int null_inactive(void *); -int null_reclaim(void *); -int null_print(void *); -int null_strategy(void *); -int null_bwrite(void *); -int null_lock(void *); -int null_unlock(void *); -int null_islocked(void *); -int null_lookup(void *); -int null_open(void *); - -/* - * This is the 10-Apr-92 bypass routine. - * This version has been optimized for speed, throwing away some - * safety checks. It should still always work, but it's not as - * robust to programmer errors. - * Define SAFETY to include some error checking code. - * - * In general, we map all vnodes going down and unmap them on the way back. - * As an exception to this, vnodes can be marked "unmapped" by setting - * the Nth bit in operation's vdesc_flags. - * - * Also, some BSD vnode operations have the side effect of vrele'ing - * their arguments. With stacking, the reference counts are held - * by the upper node, not the lower one, so we must handle these - * side-effects here. This is not of concern in Sun-derived systems - * since there are no such side-effects. - * - * This makes the following assumptions: - * - only one returned vpp - * - no INOUT vpp's (Sun's vop_open has one of these) - * - the vnode operation vector of the first vnode should be used - * to determine what implementation of the op should be invoked - * - all mapped vnodes are of our vnode-type (NEEDSWORK: - * problems on rmdir'ing mount points and renaming?) - */ -int -null_bypass(v) - void *v; -{ - struct vop_generic_args /* { - struct vnodeop_desc *a_desc; - <other random data follows, presumably> - } */ *ap = v; - register struct vnode **this_vp_p; - int error; - struct vnode *old_vps[VDESC_MAX_VPS]; - struct vnode **vps_p[VDESC_MAX_VPS]; - struct vnode ***vppp; - struct vnodeop_desc *descp = ap->a_desc; - int reles, i; - - if (null_bug_bypass) - printf ("null_bypass: %s\n", descp->vdesc_name); - -#ifdef SAFETY - /* - * We require at least one vp. - */ - if (descp->vdesc_vp_offsets == NULL || - descp->vdesc_vp_offsets[0] == VDESC_NO_OFFSET) - panic ("null_bypass: no vp's in map."); -#endif - - /* - * Map the vnodes going in. - * Later, we'll invoke the operation based on - * the first mapped vnode's operation vector. - */ - reles = descp->vdesc_flags; - for (i = 0; i < VDESC_MAX_VPS; reles >>= 1, i++) { - if (descp->vdesc_vp_offsets[i] == VDESC_NO_OFFSET) - break; /* bail out at end of list */ - vps_p[i] = this_vp_p = - VOPARG_OFFSETTO(struct vnode**,descp->vdesc_vp_offsets[i],ap); - /* - * We're not guaranteed that any but the first vnode - * are of our type. Check for and don't map any - * that aren't. (We must always map first vp or vclean fails.) - */ - if (i && (*this_vp_p == NULLVP || - (*this_vp_p)->v_op != null_vnodeop_p)) { - old_vps[i] = NULLVP; - } else { - old_vps[i] = *this_vp_p; - *(vps_p[i]) = NULLVPTOLOWERVP(*this_vp_p); - /* - * XXX - Several operations have the side effect - * of vrele'ing their vp's. We must account for - * that. (This should go away in the future.) - */ - if (reles & 1) - VREF(*this_vp_p); - } - - } - - /* - * Call the operation on the lower layer - * with the modified argument structure. - */ - error = VCALL(*(vps_p[0]), descp->vdesc_offset, ap); - - /* - * Maintain the illusion of call-by-value - * by restoring vnodes in the argument structure - * to their original value. - */ - reles = descp->vdesc_flags; - for (i = 0; i < VDESC_MAX_VPS; reles >>= 1, i++) { - if (descp->vdesc_vp_offsets[i] == VDESC_NO_OFFSET) - break; /* bail out at end of list */ - if (old_vps[i] != NULLVP) { - *(vps_p[i]) = old_vps[i]; - if (reles & 1) { - vrele(*(vps_p[i])); - } - } - - /* - * Map the possible out-going vpp - * (Assumes that the lower layer always returns - * a VREF'ed vpp unless it gets an error.) - */ - if (descp->vdesc_vpp_offset != VDESC_NO_OFFSET && - !(descp->vdesc_flags & VDESC_NOMAP_VPP) && - !error) { - /* - * XXX - even though some ops have vpp returned vp's, - * several ops actually vrele this before returning. - * We must avoid these ops. - * (This should go away when these ops are regularized.) - */ - if (descp->vdesc_flags & VDESC_VPP_WILLRELE) - goto out; - vppp = VOPARG_OFFSETTO(struct vnode***, - descp->vdesc_vpp_offset,ap); - /* - * This assumes that **vppp is a locked vnode (it is always - * so as of this writing, NetBSD-current 1995/02/16) - * - * (don't want to lock it if being called on behalf - * of lookup--it plays weird locking games depending - * on whether or not it's looking up ".", "..", etc. - */ - error = null_node_create(old_vps[0]->v_mount, **vppp, *vppp, - descp == &vop_lookup_desc ? 0 : 1); - } - } - - out: - return (error); - -} - -/* - * We handle getattr only to change the fsid. - */ -int -null_getattr(v) - void *v; -{ - struct vop_getattr_args /* { - struct vnode *a_vp; - struct vattr *a_vap; - struct ucred *a_cred; - struct proc *a_p; - } */ *ap = v; - int error; - if ((error = null_bypass(ap)) != NULL) - return (error); - /* Requires that arguments be restored. */ - ap->a_vap->va_fsid = ap->a_vp->v_mount->mnt_stat.f_fsid.val[0]; - return (0); -} - -/* - * We must handle open to be able to catch MNT_NODEV and friends. - */ -int -null_open(v) - void *v; -{ - struct vop_open_args *ap = v; - struct vnode *vp = ap->a_vp; - enum vtype lower_type = VTONULL(vp)->null_lowervp->v_type; - - - if (((lower_type == VBLK) || (lower_type == VCHR)) && - (vp->v_mount->mnt_flag & MNT_NODEV)) - return ENXIO; - - return null_bypass(ap); -} - -int -null_inactive(v) - void *v; -{ - struct vop_inactive_args *ap = v; - - /* - * Do nothing (and _don't_ bypass). - * Wait to vrele lowervp until reclaim, - * so that until then our null_node is in the - * cache and reusable. - * - * NEEDSWORK: Someday, consider inactive'ing - * the lowervp and then trying to reactivate it - * with capabilities (v_id) - * like they do in the name lookup cache code. - * That's too much work for now. - */ - VOP_UNLOCK(ap->a_vp, 0, ap->a_p); - - return (0); -} - -int -null_reclaim(v) - void *v; -{ - struct vop_reclaim_args /* { - struct vnode *a_vp; - } */ *ap = v; - struct vnode *vp = ap->a_vp; - struct null_node *xp = VTONULL(vp); - struct vnode *lowervp = xp->null_lowervp; - - /* - * Note: in vop_reclaim, vp->v_op == dead_vnodeop_p, - * so we can't call VOPs on ourself. - */ - /* After this assignment, this node will not be re-used. */ - xp->null_lowervp = NULL; - LIST_REMOVE(xp, null_hash); - FREE(vp->v_data, M_TEMP); - vp->v_data = NULL; - vrele (lowervp); - return (0); -} - - -int -null_print(v) - void *v; -{ - struct vop_print_args /* { - struct vnode *a_vp; - } */ *ap = v; - register struct vnode *vp = ap->a_vp; - - printf ("\ttag VT_NULLFS, vp=%p, lowervp=%p\n", vp, NULLVPTOLOWERVP(vp)); - vprint("nullfs lowervp", NULLVPTOLOWERVP(vp)); - return (0); -} - - -/* - * XXX - vop_strategy must be hand coded because it has no - * vnode in its arguments. - */ -int -null_strategy(v) - void *v; -{ - struct vop_strategy_args /* { - struct buf *a_bp; - } */ *ap = v; - struct buf *bp = ap->a_bp; - int error; - struct vnode *savedvp; - - savedvp = bp->b_vp; - bp->b_vp = NULLVPTOLOWERVP(bp->b_vp); - - error = VOP_STRATEGY(bp); - - bp->b_vp = savedvp; - - return (error); -} - - -/* - * XXX - like vop_strategy, vop_bwrite must be hand coded because it has no - * vnode in its arguments. - */ -int -null_bwrite(v) - void *v; -{ - struct vop_bwrite_args /* { - struct buf *a_bp; - } */ *ap = v; - struct buf *bp = ap->a_bp; - int error; - struct vnode *savedvp; - - savedvp = bp->b_vp; - bp->b_vp = NULLVPTOLOWERVP(bp->b_vp); - - error = VOP_BWRITE(bp); - - bp->b_vp = savedvp; - - return (error); -} - -/* - * We need a separate null lock routine, to avoid deadlocks at reclaim time. - * If a process holds the lower-vnode locked when it tries to reclaim - * the null upper-vnode, _and_ null_bypass is used as the locking operation, - * then a process can end up locking against itself. - * This has been observed when a null mount is set up to "tunnel" beneath a - * union mount (that setup is useful if you still wish to be able to access - * the non-union version of either the above or below union layer) - */ -int -null_lock(v) - void *v; -{ - struct vop_lock_args *ap = v; - -#if 0 - vop_generic_lock(ap); -#endif - if ((ap->a_flags & LK_TYPE_MASK) == LK_DRAIN) - return (0); - ap->a_flags &= ~LK_INTERLOCK; - - return (null_bypass((struct vop_generic_args *)ap)); -} - -int -null_unlock(v) - void *v; -{ - struct vop_unlock_args *ap = v; -#if 0 - vop_generic_unlock(ap); -#endif - ap->a_flags &= ~LK_INTERLOCK; - - return (null_bypass((struct vop_generic_args *)ap)); -} - -int -null_islocked(v) - void *v; -{ - /* XXX */ - return (0); -} - -int -null_lookup(v) - void *v; -{ - register struct vop_lookup_args /* { - struct vnodeop_desc *a_desc; - struct vnode *a_dvp; - struct vnode **a_vpp; - struct componentname *a_cnp; - } */ *ap = v; - register int error; - int flags = ap->a_cnp->cn_flags; - struct componentname *cnp = ap->a_cnp; -#if 0 - register struct vnode *dvp, *vp; - struct proc *p = cnp->cn_proc; - struct vop_unlock_args unlockargs; - struct vop_lock_args lockargs; -#endif - -#ifdef NULLFS_DIAGNOSTIC - printf("null_lookup: dvp=%lx, name='%s'\n", - ap->a_dvp, cnp->cn_nameptr); -#endif - - if ((flags & ISLASTCN) && (ap->a_dvp->v_mount->mnt_flag & MNT_RDONLY) && - (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) - return (EROFS); - error = null_bypass((struct vop_generic_args *)ap); - if (error == EJUSTRETURN && (flags & ISLASTCN) && - (ap->a_dvp->v_mount->mnt_flag & MNT_RDONLY) && - (cnp->cn_nameiop == CREATE || cnp->cn_nameiop == RENAME)) - error = EROFS; - -#if 0 - /* - * We must do the same locking and unlocking at this layer as - * is done in the layers below us. We could figure this out - * based on the error return and the LASTCN, LOCKPARENT, and - * LOCKLEAF flags. However, it is more expidient to just find - * out the state of the lower level vnodes and set ours to the - * same state. - */ - dvp = ap->a_dvp; - vp = *ap->a_vpp; - if (dvp == vp) - return (error); - if (!VOP_ISLOCKED(dvp)) { - unlockargs.a_vp = dvp; - unlockargs.a_flags = 0; - unlockargs.a_p = p; - vop_generic_unlock(&unlockargs); - } - if (vp != NULLVP && VOP_ISLOCKED(vp)) { - lockargs.a_vp = vp; - lockargs.a_flags = LK_SHARED; - lockargs.a_p = p; - vop_generic_lock(&lockargs); - } -#endif - return (error); -} +#include <miscfs/genfs/layer_extern.h> /* * Global vfs data structures */ -int (**null_vnodeop_p)(void *); -struct vnodeopv_entry_desc null_vnodeop_entries[] = { - { &vop_default_desc, null_bypass }, - - { &vop_getattr_desc, null_getattr }, - { &vop_inactive_desc, null_inactive }, - { &vop_reclaim_desc, null_reclaim }, - { &vop_print_desc, null_print }, - - { &vop_open_desc, null_open }, /* mount option handling */ - - { &vop_lock_desc, null_lock }, - { &vop_unlock_desc, null_unlock }, - { &vop_islocked_desc, null_islocked }, - { &vop_lookup_desc, null_lookup }, /* special locking frob */ - - { &vop_strategy_desc, null_strategy }, - { &vop_bwrite_desc, null_bwrite }, - - { NULL, NULL } +int (**nullfs_vnodeop_p)(void *); +struct vnodeopv_entry_desc nullfs_vnodeop_entries[] = { + { &vop_default_desc, layer_bypass }, + + { &vop_lookup_desc, layer_lookup }, + { &vop_setattr_desc, layer_setattr }, + { &vop_getattr_desc, layer_getattr }, + { &vop_access_desc, layer_access }, + { &vop_lock_desc, layer_lock }, + { &vop_unlock_desc, layer_unlock }, + { &vop_islocked_desc, layer_islocked }, + { &vop_fsync_desc, layer_fsync }, + { &vop_inactive_desc, layer_inactive }, + { &vop_reclaim_desc, layer_reclaim }, + { &vop_print_desc, layer_print }, + + { &vop_open_desc, layer_open }, /* mount option handling */ + + { &vop_strategy_desc, layer_strategy }, + { &vop_bwrite_desc, layer_bwrite }, + { &vop_bmap_desc, layer_bmap }, + + { NULL, NULL } }; -struct vnodeopv_desc null_vnodeop_opv_desc = - { &null_vnodeop_p, null_vnodeop_entries }; +const struct vnodeopv_desc nullfs_vnodeop_opv_desc = + { &nullfs_vnodeop_p, nullfs_vnodeop_entries }; |