Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Fix the experimental NFS client so that it does not bogusly
set the f_flags field of "struct statfs". This had the interesting
effect of making the NFSv4 mounts "disappear" after r221014,
since NFSMNT_NFSV4 and MNT_IGNORE became the same bit.
Move the files used for a diskless NFS root from sys/nfsclient
to sys/nfs in preparation for them to be used by both NFS
clients. Also, move the declaration of the three global data
structures from sys/nfsclient/nfs_vfsops.c to sys/nfs/nfs_diskless.c
so that they are defined when either client uses them.

Reviewed by: jhb
MFC after: 2 weeks

Cleanup and split of nfs client and server code.
This builds on the top of several repo-copies.

KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after: ha ha ha ha

$Id$ -> $FreeBSD$

Forward declare more structs that are used in prototypes here - don't
depend on <sys/types.h> forward declaring common ones.

Added an underscore to `sin' in prototypes to avoid warnings for the
conflict with the ANSI sin().

Fix all areas of the system (or at least all those in LINT) to avoid storing
socket addresses in mbufs. (Socket buffers are the one exception.) A number
of kernel APIs needed to get fixed in order to make this happen. Also,
fix three protocol families which kept PCBs in mbufs to not malloc them
instead. Delete some old compatibility cruft while we're at it, and add
some new routines in the in_cksum family.

Remove unused routines.

Bring in some kernel bootp support. This removes the need for netboot
to fill in the nfs_diskless structure, at the cost of some kernel
bloat. The advantage is that this code works on a wider range of
network adapters than netboot. Several new kernel options are
documented in LINT.
Obtained from: parts of the code comes from NetBSD.