Use information about suported diagnostic pages to avoid reading optional
Element Descriptor page if it is not supported.  This removes one error
message from verbose logs during boot on systems with some enclosures.

Sponsored by:	iXsystems, Inc.
sh: Test that a redefined alias works.
Sort option parsing as far as practical.
Implement DTrace for PowerPC.  This includes both 32-bit and 64-bit.

There is one known issue:  Some probes will display an error message along the
lines of:  "Invalid address (0)"

I tested this with both a simple dtrace probe and dtruss on a few different
binaries on 32-bit.  I only compiled 64-bit, did not run it, but I don't expect
problems without the modules loaded.  Volunteers are welcome.

MFC after:	1 month
Update AP96 to directly attach an arswitch.
Add y flag and environment variable LS_SAMESORT to specify the same
sorting order for time and name with the -t option.  IEEE Std 1003.2
(POSIX.2) mandates that the -t option sort in descending order, and
that if two files have the same timestamp, they should be sorted in
ascending order of their names.  The -r flag reverses both of these
sort orders, so they're never the same.  This creates significant
problems for sequentially named files stored on FAT file systems,
where it can be impossible to list them in the order in which they
were created.

Add , (comma) option to print file sizes grouped and separated by
thousands using the non-monetary separator returned by localeconv(3),
typically a comma or period.

MFC after:  14 days
Add support for SCSI pass through devices to be attached and
detached.

PR:		172864
Submitted by:	rstone@
- Current caching mode is completely broken because it simply relies
  on timing of the operations and not real lookup, bringing too many
  false positives. Remove the whole mechanism. If it needs to be
  implemented, next time it should really be done in the proper way.
- Fix VOP_GETATTR() in order to cope with userland bugs that would
  change the type of file and not panic. Instead it gets the entry as
  if it is not existing.

Reported and tested by:	flo
MFC after:	2 months
X-MFC:		241519, 242536,242616
ICMPV6_FILTER should read ICMP6_FILTER.

Submitted by:	Frédéric Perrin <frederic.perrin resel.fr>
MFC after:	2 weeks
Use .PATH instead of VPATH.

Reviewed by:	gnn,rwatson
 - Implement BIO_FLUSH support around journal entries.  This will not 100%
   solve power loss problems with dishonest write caches.  However, it
   should improve the situation and force a full fsck when it is unable
   to resolve with the journal.
 - Resolve a case where the journal could wrap in an unsafe way causing
   us to prematurely lose journal entries in very specific scenarios.

Discussed with:	mckusick
MFC after:	1 month
 - Change ULE to use dynamic slice sizes for the timeshare queue in order
   to further reduce latency for threads in this queue.  This should help
   as threads transition from realtime to timeshare.  The latency is
   bound to a max of sched_slice until we have more than sched_slice / 6
   threads runnable.  Then the min slice is allotted to all threads and
   latency becomes (nthreads - 1) * min_slice.

Discussed with: mav
Add DTrace to 32-bit PowerPC GENERIC now.

MFC after:	1 month
Clarify that the ' flag is an apostrophe.

MFC after:	2 weeks
Make parameters to -c and -k options optional.  If no parameters are
supplied, print information for all keywords.

Improve output of -c option, in particular in conjunction with -k
option.

MFC after:	14 days
Zero the newly allocated md(4) swap-backed page to prevent random
kernel memory leakage to userspace. For the typical use, when a
filesystem put on the md disk, the change only results in CPU and
memory bandwidth spent to zero the page, since filsystems make sure
that user never see unwritten content.  But if md disk is used as raw
device by userspace, the garbage is exposed.

Reported by:	Paul Schenkeveld <freebsd@psconsult.nl>
MFC after:	2 weeks
Cleanup some whitspace in this file to get it out of an upcoming patch.

MFC after:	10 days
Reduce differences between these two initarms a bit more.
Make r242655 build on sparc64. While at it, make vm_{max,min}_kernel_address
vm_offset_t as they should be.
Add new USB device ID.