diff options
Diffstat (limited to 'sys/miscfs/nullfs/null_vfsops.c')
-rw-r--r-- | sys/miscfs/nullfs/null_vfsops.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/sys/miscfs/nullfs/null_vfsops.c b/sys/miscfs/nullfs/null_vfsops.c new file mode 100644 index 0000000..b0d2df7 --- /dev/null +++ b/sys/miscfs/nullfs/null_vfsops.c @@ -0,0 +1,366 @@ +/* + * 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. + * + * @(#)null_vfsops.c 8.2 (Berkeley) 1/21/94 + * + * @(#)lofs_vfsops.c 1.2 (Berkeley) 6/18/92 + * $Id: lofs_vfsops.c,v 1.9 1992/05/30 10:26:24 jsp Exp jsp $ + */ + +/* + * Null Layer + * (See null_vnops.c for a description of what this does.) + */ + +#include <sys/param.h> +#include <sys/systm.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 <miscfs/nullfs/null.h> + +/* + * Mount null layer + */ +int +nullfs_mount(mp, path, data, ndp, p) + struct mount *mp; + char *path; + caddr_t data; + 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; + u_int size; + +#ifdef NULLFS_DIAGNOSTIC + printf("nullfs_mount(mp = %x)\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);*/ + } + + /* + * Get argument + */ + if (error = copyin(data, (caddr_t)&args, sizeof(struct null_args))) + return (error); + + /* + * Find lower node + */ + NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF, + UIO_USERSPACE, args.target, p); + if (error = namei(ndp)) + return (error); + + /* + * Sanity check on lower vnode + */ + lowerrootvp = ndp->ni_vp; + + vrele(ndp->ni_dvp); + ndp->ni_dvp = NULL; + + xmp = (struct null_mount *) malloc(sizeof(struct null_mount), + M_UFSMNT, M_WAITOK); /* XXX */ + + /* + * Save reference to underlying FS + */ + xmp->nullm_vfs = lowerrootvp->v_mount; + + /* + * Save reference. Each mount also holds + * a reference on the root vnode. + */ + error = null_node_create(mp, lowerrootvp, &vp); + /* + * Unlock the node (either the lower or the alias) + */ + VOP_UNLOCK(vp); + /* + * Make sure the node alias worked + */ + if (error) { + vrele(lowerrootvp); + free(xmp, M_UFSMNT); /* XXX */ + return (error); + } + + /* + * 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; + getnewfsid(mp, MOUNT_LOFS); + + (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); +#ifdef NULLFS_DIAGNOSTIC + printf("nullfs_mount: lower %s, alias at %s\n", + 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 +nullfs_unmount(mp, mntflags, p) + struct mount *mp; + int mntflags; + struct proc *p; +{ + struct vnode *nullm_rootvp = MOUNTTONULLMOUNT(mp)->nullm_rootvp; + int error; + int flags = 0; + extern int doforce; + +#ifdef NULLFS_DIAGNOSTIC + printf("nullfs_unmount(mp = %x)\n", mp); +#endif + + if (mntflags & MNT_FORCE) { + /* lofs can never be rootfs so don't check for it */ + if (!doforce) + return (EINVAL); + flags |= FORCECLOSE; + } + + /* + * Clear out buffer cache. I don't think we + * ever get anything cached at this level at the + * moment, but who knows... + */ +#if 0 + mntflushbuf(mp, 0); + if (mntinvalbuf(mp, 1)) + return (EBUSY); +#endif + if (nullm_rootvp->v_usecount > 1) + return (EBUSY); + if (error = vflush(mp, nullm_rootvp, flags)) + return (error); + +#ifdef NULLFS_DIAGNOSTIC + vprint("alias root of lower", nullm_rootvp); +#endif + /* + * Release reference on underlying root vnode + */ + vrele(nullm_rootvp); + /* + * And blow it away for future re-use + */ + vgone(nullm_rootvp); + /* + * Finally, throw away the null_mount structure + */ + free(mp->mnt_data, M_UFSMNT); /* XXX */ + mp->mnt_data = 0; + return 0; +} + +int +nullfs_root(mp, vpp) + struct mount *mp; + struct vnode **vpp; +{ + struct vnode *vp; + +#ifdef NULLFS_DIAGNOSTIC + printf("nullfs_root(mp = %x, vp = %x->%x)\n", mp, + MOUNTTONULLMOUNT(mp)->nullm_rootvp, + NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp) + ); +#endif + + /* + * Return locked reference to root. + */ + vp = MOUNTTONULLMOUNT(mp)->nullm_rootvp; + VREF(vp); + VOP_LOCK(vp); + *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; +{ + 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 = %x, vp = %x->%x)\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_type = mstat.f_type; + 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); + } + 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, nam, vpp, exflagsp, credanonp) + struct mount *mp; + struct fid *fidp; + struct mbuf *nam; + struct vnode **vpp; + int *exflagsp; + struct ucred**credanonp; +{ + + return VFS_FHTOVP(MOUNTTONULLMOUNT(mp)->nullm_vfs, fidp, nam, vpp, exflagsp,credanonp); +} + +int +nullfs_vptofh(vp, fhp) + struct vnode *vp; + struct fid *fhp; +{ + return VFS_VPTOFH(NULLVPTOLOWERVP(vp), fhp); +} + +int nullfs_init __P((void)); + +struct vfsops null_vfsops = { + nullfs_mount, + nullfs_start, + nullfs_unmount, + nullfs_root, + nullfs_quotactl, + nullfs_statfs, + nullfs_sync, + nullfs_vget, + nullfs_fhtovp, + nullfs_vptofh, + nullfs_init, +}; |