K 10
svn:author
V 3
yar
K 8
svn:date
V 27
2008-02-14T17:04:31.000000Z
K 7
svn:log
V 838
In the new order of things dictated by nmount(2), a read-only mount
is to be requested via a "ro" option.  At the same time, MNT_RDONLY
is gradually becoming an indicator of the current state of the FS
instead of a command flag.  Today passing MNT_RDONLY alone to the
kernel's mount machinery will lead to various glitches.  (See the
PRs for examples.)

Therefore mount the root FS with a "ro" option instead of the
MNT_RDONLY flag.  (Note that MNT_RDONLY still is added to the mount
flags internally, by vfs_donmount(), if "ro" was specified.)

To be able to pass "ro" cleanly to kernel_vmount(), teach the latter
function to accept options with NULL values.

Also correct the comment explaining how mount_arg() handles length
of -1.

PR:		bin/106636 kern/120319
Submitted by:	Jaakko Heinonen <see PR kern/120319 for email> (originally)

END