size != 512 that are configured without a label. The bug should only
have effected swap-backed VN mounts without a label.
Add several major features to VN. In the kernel we add a swap
pre-reservation capability, which can be used to guarentee seek
consistency for swap-backed VN nodes. This also incidently allows
a swap-backed VN filesystem to be recovered after a crash in some
cases (if the same swap blocks happen to be reserved).
We also add a number of new options to vnconfig which do the work
of pre-zeroing or creating/truncating/extending a file which greatly
simplifies using VN in a file-backed configuration.
Add FreeBSD CVS label to sys/sys/vnioctl.h, as well as a new ioctl
flag for the swap pre-reservation feature.
Reviewed by: Alan Cox <alc@cs.rice.edu>, David Greenman <dg@root.com>