[src/trunk]: src/sys/ufs/ffs Add a stub file so that snapshot support can be ...

[dsl <dsl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/c0e41d6e4b01
branches:  trunk
changeset: 573812:c0e41d6e4b01
user:      dsl <dsl%NetBSD.org@localhost>
date:      Thu Feb 10 22:22:32 2005 +0000

description:
Add a stub file so that snapshot support can be compiled out.
Will allow INSTALL_TINY to fit back in its designated space.
Since the calling code doesn't allow a snapshot mount to fail, this code
will output a warning and delete any snapshots it finds.
This only happend on rw mounts - snapshots don't seem to be created
when mounting ro.
The whole way the snapshots gets mounted is a PITA anyway, the superblock
'last mounted' time should be used to validate that the fs hasn't been
mounted elsewhere.

diffstat:

 sys/ufs/ffs/ffs_snapshot_stub.c |  145 ++++++++++++++++++++++++++++++++++++++++
 1 files changed, 145 insertions(+), 0 deletions(-)

diffs (149 lines):

diff -r 165bd69896fb -r c0e41d6e4b01 sys/ufs/ffs/ffs_snapshot_stub.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/sys/ufs/ffs/ffs_snapshot_stub.c   Thu Feb 10 22:22:32 2005 +0000
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2000 Marshall Kirk McKusick. All Rights Reserved.
+ *
+ * Further information about snapshots can be obtained from:
+ *
+ *     Marshall Kirk McKusick          http://www.mckusick.com/softdep/
+ *     1614 Oxford Street              mckusick%mckusick.com@localhost
+ *     Berkeley, CA 94709-1608         +1-510-843-9542
+ *     USA
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY MARSHALL KIRK MCKUSICK ``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 MARSHALL KIRK MCKUSICK 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.
+ *
+ *     @(#)ffs_snapshot.c      8.11 (McKusick) 7/23/00
+ *
+ *     from FreeBSD: ffs_snapshot.c,v 1.79 2004/02/13 02:02:06 kuriyama Exp
+ */
+
+#include <sys/cdefs.h>
+__KERNEL_RCSID(0, "$NetBSD: ffs_snapshot_stub.c,v 1.1 2005/02/10 22:22:32 dsl Exp $");
+
+#if defined(_KERNEL_OPT)
+#include "opt_ffs.h"
+#endif
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/conf.h>
+#include <sys/buf.h>
+#include <sys/proc.h>
+#include <sys/namei.h>
+#include <sys/sched.h>
+#include <sys/stat.h>
+#include <sys/malloc.h>
+#include <sys/mount.h>
+#include <sys/resource.h>
+#include <sys/resourcevar.h>
+#include <sys/vnode.h>
+
+#include <miscfs/specfs/specdev.h>
+
+#include <ufs/ufs/quota.h>
+#include <ufs/ufs/ufsmount.h>
+#include <ufs/ufs/inode.h>
+#include <ufs/ufs/ufs_extern.h>
+#include <ufs/ufs/ufs_bswap.h>
+
+#include <ufs/ffs/fs.h>
+#include <ufs/ffs/ffs_extern.h>
+
+
+/*
+ * Create a snapshot file and initialize it for the filesystem.
+ * Vnode is locked on entry and return.
+ */
+int
+ffs_snapshot(struct mount *mp, struct vnode *vp, struct timespec *ctime)
+{
+       return ENODEV;
+}
+
+/*
+ * Decrement extra reference on snapshot when last name is removed.
+ * It will not be freed until the last open reference goes away.
+ */
+void
+ffs_snapgone(struct inode *ip)
+{
+}
+
+/*
+ * Prepare a snapshot file for being removed.
+ */
+void
+ffs_snapremove(struct vnode *vp)
+{
+}
+
+/*
+ * Notification that a block is being freed. Return zero if the free
+ * should be allowed to proceed. Return non-zero if the snapshot file
+ * wants to claim the block. The block will be claimed if it is an
+ * uncopied part of one of the snapshots. It will be freed if it is
+ * either a BLK_NOCOPY or has already been copied in all of the snapshots.
+ * If a fragment is being freed, then all snapshots that care about
+ * it must make a copy since a snapshot file can only claim full sized
+ * blocks. Note that if more than one snapshot file maps the block,
+ * we can pick one at random to claim it. Since none of the snapshots
+ * can change, we are assurred that they will all see the same unmodified
+ * image. When deleting a snapshot file (see ffs_snapremove above), we
+ * must push any of these claimed blocks to one of the other snapshots
+ * that maps it. These claimed blocks are easily identified as they will
+ * have a block number equal to their logical block number within the
+ * snapshot. A copied block can never have this property because they
+ * must always have been allocated from a BLK_NOCOPY location.
+ */
+int
+ffs_snapblkfree(struct fs *fs, struct vnode *devvp, daddr_t bno, long size, ino_t inum)
+{
+       return 0;
+}
+
+/*
+ * Associate snapshot files when mounting.
+ */
+void
+ffs_snapshot_mount(struct mount *mp)
+{
+       struct ufsmount *ump = VFSTOUFS(mp);
+       struct fs *fs = ump->um_fs;
+       int snaploc;
+
+       printf("ffs_snapshot_mount: snapshots not supported, being deleted\n");
+
+       for (snaploc = 0; snaploc < FSMAXSNAP; snaploc++)
+               fs->fs_snapinum[snaploc] = 0;
+}
+
+/*
+ * Disassociate snapshot files when unmounting.
+ */
+void
+ffs_snapshot_unmount(struct mount *mp)
+{
+}