Remove file that need not have been imported.
Flatten GNU libregex vendor area.
Import libregex from GNU libc 2.17.
Add missing buffer releases (brelse) after bread calls that return
an error. One could argue that returning a buffer even when it is
not valid is incorrect, but bread has always returned a buffer
valid or not.

Reviewed by: kib
MFC after:   2 weeks
Implement beacon event debugging in athalq.
Fix NULL-dereference kernel panic in case of mps_attach() failure.

MFC after:	1 week
Properly spell sentinel (missed in 250891)
No functional changes.

Spotted by:  Navdeep Parhar and Alexey Dokuchaev
MFC after:   2 weeks
Regenerate with manual fixup for WITH_LDNS_UTILS inheriting WITHOUT_BIND_UTILS.
Fix a copy-and-paste typo.
Acquire read lock on the src object for vm_fault_copy_entry().

Sponsored by:	EMC / Isilon storage division
Reviewed by:	alc
Increase the (arbitrary) limit for the number of packets per tick
from 1k to 20k The previous value was good 10 years ago, but not
anymore now.

More importantly, lots of good surprises:
polling is incredibly effective under virtualization, and not only
prevents livelock but also saves most of the VM exit overhead in
receive mode.

Using polling, a FreeBSD instance under qemu-kvm remains perfectly
responsive even when bombed with 10 Mpps over an emulated e1000,
and happily processes 1.7 Mpps through ipfw.

Note that some incompatibilities still remain: e.g. polling is not
(yet) compatible with netmap, and seems to freeze the guest when
kern.polling.idle_poll=1

MFC after:	3 days
Remove reference to removed !MPSAFE filesystem support
Correct panic on detach of Xen PV network interfaces.

dev/xen/netfront:
    In netif_free(), properly stop the interface and drain any pending
    timers prior to disconnecting from the backend device.

    Remove all media and detach our interface object from the system
    prior to deleting it.

PR:		kern/176471
Submitted by:	Roger Pau Monne <roger.pau@citrix.com>
Reviewed by:	gibbs
MFC after:	1 week
Improve compatibility with old flex and fix build with GCC.
Don't mess with /etc/localtime if it is a symlink.
Fix loss of the emulated keyboard on Xen PV HVM domains.

xen/xenbus/xenbusb.c:
    In xenbusb_probe_children(), do not modify the XenBus state of
    devices for which we have no PV driver support. An emulated device
    we do support may share this backend.  Hide the node from XenBus
    instead.

    This prevents closing the vkbd device, which Qemu's emulated keyboard
    device is using as the source for keyboard events.

    Tested with qemu-xen-traditional, qemu-xen and qemu stubdomains, all
    working as expected.

Submitted by:	Roger Pau Monne <roger.pau@citrix.com>
Reviewed by:	gibbs
MFC after:	1 week
Don't depend on the touch binary being present.

We can simply create an empty file by doing a no-op and redirecting stdout.
Work around build breakages with GCC 4.2.

Reported by:	tinderbox
Switch to AP[2:1] access permissions model. Store "referenced"
bit in PTE.

Enable Access Flag in CPU control. With AF enabled each valid mapping
needs to have referenced bit in PTE set in order to be able to cache
it in the TLB.

AP[0] bit is to be used as reference flag.
All access permissions are encoded by AP[2:1] wherein AP[1] is in fact
"user enable" and AP[2](APX) is "write disable".

All mappings are always set to be valid. Reference emulation is performed
by setting/clearing reference flag in PTE.

md.pvh_attrs are no longer necessary however pv_flags are still being used
for now.

Marking vm_page as "dirty" or "referenced" is being performed on:
- page or flag fault servicing in pmap_fault_fixup(), basing on the fault
  type
- vm_fault servicing in pmap_enter() according to the desired protections
  and faulty access type
Redundant page marking has been removed as on ARM we know exactly when the
particular page is referenced or is going to be written.

Submitted by:	Zbigniew Bodek <zbb@semihalf.com>
Sponsored by:	The FreeBSD Foundation, Semihalf
Improve, optimize and clean-up ARMv6/v7 memory management related code.

Use pmap_find_pv if needed instead of multiplying its code throughout
pmap-v6.

Avoid possible NULL pointer dereference in pmap_enter_locked()
When trying to get m->md.pv_memattr, make sure that m != NULL,
in particular that vector_page is set to be NULL.

Do not set PGA_REFERENCED flag in pmap_enter_pv().
On ARM any new page reference will result in either entering the new
mapping by calling pmap_enter, etc. or fixing-up the existing mapping in
pmap_fault_fixup().
Therefore we set PGA_REFERENCED flag in the earlier mentioned cases and
setting it later in pmap_enter_pv() is just waste of cycles.

Delete unused pm_pdir pointer from the pmap structure.

Rearrange brackets in the fault cause detection in trap.c
Place the brackets correctly in order to see course of the conditions
instantaneously.

Unify naming in pmap-v6.c and improve style
Use naming common for whole pmap and compatible with other pmaps,
improve style where possible:
pm   -> pmap
pg   -> m
opg  -> om
*pt  -> *ptep
*pte -> *ptep
*pde -> *pdep

Submitted by:   Zbigniew Bodek <zbb@semihalf.com>
Sponsored by:   The FreeBSD Foundation, Semihalf