freebsd-dev/sbin/umount/umount.8
Brian Feldman bc70c1725f quoting << Martin_Blapp
-	Completly changed the internals of umount(8). We do three
	checks now to see if 'argv' is in the mounttable. It they
	all fail, we return to main and print a warning.

-	fixed the umount mount-order. The checks are rather complex
	to do this. Cause umount(8) should also be able to unmount
	several devices at once ('umount -a', 'umount -A',
	'umount /mnt /mnt2'), the mount-order get's important.
	I added checks to mark and unmark already unmounted devices.

- 	Various fixes with nfs-unmounts (no rpc-calls were done,
	or they were done although there was an existing mount).
	Since we allow overlay-mounts, we should also handle them
	properly.

-	Translate the deprecated nfs-syntax with '@' to ':' like
	mount_nfs does. The ':' syntax has now precedence, but '@'
	still works.

-	'umount -v' is now fixed for all cases and doesn't print
	garbage like two times the mountpoint etc.

-	removed non documented and useless umount '-F'.

-	hanged nfsmounts can now unmounted 'without' any problems.
	I've removed stat() and realpath() checks on the mountpoint.
	Instead we just do a realpath() on the basedir of the
	mountpath and add the dirname again.
	Implemented this as an idea from phk. But there are still
	vfs-restrictions if the nfs_mount is busy. If there are
	unwritten metadata on a hanged nfs-mount, and we modify
	nfs_vfsops.c to not return EBUSY, we get a deadlock :(
	The problem has now moved from userland to kernel.

-	removed the BUGS part from the umount(8) manpage.

-	Converted it to ANSI C (more than 60% of the code have
	changed).

Martin_Blapp

Fixed PR's
----------

o [1999/02/03] bin/9893                 NFS umount of regular file impossible

s [1995/11/27] bin/841			stale nfs mounts cannot be umounted

o [1999/08/01] bin/12911	alfred  NFS umounts are not properly done
					if just the mountpoint gets umounted

Only partially solved:
----------------------

The problem is now in kernel:

o [1999/04/07] bin/11005		`umount -f' does not work if the
					NFS-server is down.

PR:		bin/9893 bin/841 bin/12911 bin/11005
Submitted by:	Martin Blapp <mb@imp.ch>
1999-10-17 16:26:58 +00:00

130 lines
3.7 KiB
Groff

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.\" @(#)umount.8 8.2 (Berkeley) 5/8/95
.\" $FreeBSD$
.\"
.Dd May 8, 1995
.Dt UMOUNT 8
.Os BSD 4
.Sh NAME
.Nm umount
.Nd unmount filesystems
.Sh SYNOPSIS
.Nm umount
.Op Fl fv
.Ar special \&| node
.Nm umount
.Fl a | A
.Op Fl fv
.Op Fl h Ar host
.Op Fl t Ar type
.Sh DESCRIPTION
The
.Nm
command
calls the
.Xr unmount 2
system call to remove a
.Ar "special device"
or the remote node (rhost:path) from the filesystem tree at the point
.Ar node .
If either
.Ar special
or
.Ar node
are not provided, the appropriate information is taken from the
.Xr fstab 5
file.
.Pp
The options are as follows:
.Bl -tag -width indent
.It Fl a
All the filesystems described in
.Xr fstab 5
are unmounted.
.It Fl A
All the currently mounted filesystems except
the root are unmounted.
.It Fl f
The filesystem is forcibly unmounted.
Active special devices continue to work,
but all other files return errors if further accesses are attempted.
The root filesystem cannot be forcibly unmounted.
.It Fl h Ar host
Only filesystems mounted from the specified host will be
unmounted.
This option implies the
.Fl A
option and, unless otherwise specified with the
.Fl t
option, will only unmount
.Tn NFS
filesystems.
.It Fl t Ar type
Is used to indicate the actions should only be taken on
filesystems of the specified type.
More than one type may be specified in a comma separated list.
The list of filesystem types can be prefixed with
.Dq no
to specify the filesystem types for which action should
.Em not
be taken.
For example, the
.Nm
command:
.Bd -literal -offset indent
umount -a -t nfs,mfs
.Ed
.Pp
umounts all filesystems of the type
.Tn NFS
and
.Tn MFS .
.It Fl v
Verbose, additional information is printed out as each filesystem
is unmounted.
.El
.Sh FILES
.Bl -tag -width /etc/fstab -compact
.It Pa /etc/fstab
filesystem table
.El
.Sh SEE ALSO
.Xr unmount 2 ,
.Xr fstab 5 ,
.Xr mount 8
.Sh HISTORY
A
.Nm
command appeared in
.At v6 .