Initial snapshot of work to eliminate 64K MAXPHYS.  Basically works for
physio (I/O to raw devices); needs more doing to get it going with the
filesystems, but it shouldn't damage data.

All work's been done on amd64 so far.  Not hard to add support to other
ports.  If others want to pitch in, one very helpful thing would be to
sort out when and how IDE disks can do 128K or larger transfers, and
adjust the various PCI IDE (or at least ahcisata) drivers and wd.c
accordingly -- it would make testing much easier.  Another very helpful
thing would be to implement a smart minphys() for RAIDframe along the
lines detailed in the MAXPHYS-NOTES file.
ATF wrapping of the npf tests
apply fix for CVE-2012-4244 from upstream

upstream changelog:
          --- 9.9.1-P3 released ---

   3364.  [security]      Named could die on specially crafted record.
                          [RT #30416]
Implement dynamic NPF extensions interface.  An extension consists of
dynamically loaded module (.so) supplementing npfctl(8) and a kernel
module.  Move normalisation and logging functionality into their own
extensions.  More improvements to come.
*Sigh* provide, by default, the dumb "allocate 64K on the stack" variant
of the lzf_compress API by default.  This is because there is evidently
code floating around out there in the world with broken autoconf scripts that
don't check for LZF_STATE_ARG in the lzf header files and just assume the
dumb version of the API.

We rename the sane API to lzf_compress_r and implement the dumb API in
terms of it.  Consequently, bump liblzf major version number.  This is
fine because nothing used our liblzf with the old API.

Add lzf(1) utility from LZF distribution.  Add manual page for lzf(1).
Take wiz's suggestion.
Try to make this test gracefully fail when npftest is not available
Update LLVM/Clang snapshot to r164464. This adopts the GCC options for
the SSP parameters and a not-yet-default rewrite of SROA.
Add regression test for cdbr(3) and cdbw(3).
Remove magic numbers.
Initial import of sljit @ r175.

svn co https://sljit.svn.sourceforge.net/svnroot/sljit@r175 dist
Adapt code to compile with -D_KERNEL.
from hostap.epitest.fi
Support transfers of up to MACHINE_MAXPHYS in all pciide variants, and ahci.
wd(4) limits its maxphys depending on the drives's capability (64k sectors
for LBA48, 256 sectors for LBA and 128 sectors for older devices).

I assumed all pciide controllers could do MACHINE_MAXPHYS transfers, but
this may not be true. The capabilities of each controller variants should be
looked at more closely.
Fix panic "bad chunksize ..." in read-ahead code:
- off comes from the pager, so should already be page-aligned.
  KASSERT() that it is, and remove the off = trunc_page(off)
- as off is not changed any more, the size of the transfer is chunksize.
  Don't compute bytelen any more,  which is what required chunksize
  to be a power of 2. KASSERT() that chunksize is a multiple of page size.
Redo previous: it seems that the point of the bytelen computation was to
get transfers aligned to chunksz. So reintroduce the code, but using chunksz
instead of chunksize (if the readahead is trucated there's no point in
trying to align it anyway).
Now I get 64k read requests at the drive level again.
Use mnt_maxphys not MAXPHYS to limit the size of I/O to disk.
Now the read-ahead code does issue 512k requests to disk.
We know vp is not NULL, no need to check
The pagedaemon ca emit write as large as the underlying device's maxphys,
so emergva size needs to be MACHINE_MAXPHYS, MAXPHYS is not enough.
take care of the signal safe syslog calls which are not exposed.