Fix after r255014
Don't return an error for socket timeouts that are too large.  Just
cap them to INT_MAX ticks instead.

PR:		kern/181416 (r254699 really)
Requested by:	bde
MFC after:	2 weeks
Work-around a timing problem with the ITE IT8513E now that the core
calls ns8250_bus_ipend() almost immediately after ns8250_bus_attach().
As it appears, a line break condition is being signalled for almost
all received characters due to this. A delay of 150ms seems enough
to allow the H/W to settle and to avoid the problem.
More analysis is needed, but for now a regression has been addressed.

Reported by: kevlo@
Tested by: kevlo@
Fix some issues in change 254760 pointed out by Bruce Evans:

 - Remove excessive parenthesis
 - Use KNF continuation indentation
 - Cut down on excessive continuation lines
 - More consistent style in messages
 - Use uprintf() instead of printf()

Submitted by:	bde
Update to 2013-08-29 NetBSD libexecinfo snapshot

This adds my patch to use the kern.proc.pathname sysctl instead of
relying on procfs(5).
Add a few missing language directories for /usr.
Add directories that is installed as part of bsdconfig.

These are included unconditionally for now because bsdconfig
is currently installed unconditionally.

This fixes 'make -j 17 installworld' caused by a race
condition.

MFC candidate.
Fix atomic operations on context_flag without altering semantics.
Convert the if_lagg rwlock to an rmlock.

We've been seeing lots of cache line contention (but not lock contention!)
in our workloads between the various TX and RX threads going on.

The write lock is only grabbed when configuration changes are made - which
are infrequent.

With this patch, the contention and cycles spent waiting for updates
disappear.

Sponsored by:	Netflix, Inc.
- Remove test_and_set_bit() macro.  It is unused since r255037.
- Relax atomic_read() and atomic_set() macros.  Linux does not require any
memory barrier.  Also, these macros may be even reordered or optimized away
according to the API documentation:

https://www.kernel.org/doc/Documentation/atomic_ops.txt
Implement vector callback for PVHVM and unify event channel implementations

Re-structure Xen HVM support so that:
	- Xen is detected and hypercalls can be performed very
	  early in system startup.
	- Xen interrupt services are implemented using FreeBSD's native
	  interrupt delivery infrastructure.
	- the Xen interrupt service implementation is shared between PV
	  and HVM guests.
	- Xen interrupt handlers can optionally use a filter handler
	  in order to avoid the overhead of dispatch to an interrupt
	  thread.
	- interrupt load can be distributed among all available CPUs.
	- the overhead of accessing the emulated local and I/O apics
	  on HVM is removed for event channel port events.
	- a similar optimization can eventually, and fairly easily,
	  be used to optimize MSI.

Early Xen detection, HVM refactoring, PVHVM interrupt infrastructure,
and misc Xen cleanups:

Sponsored by: Spectra Logic Corporation

Unification of PV & HVM interrupt infrastructure, bug fixes,
and misc Xen cleanups:

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D

sys/x86/x86/local_apic.c:
sys/amd64/include/apicvar.h:
sys/i386/include/apicvar.h:
sys/amd64/amd64/apic_vector.S:
sys/i386/i386/apic_vector.s:
sys/amd64/amd64/machdep.c:
sys/i386/i386/machdep.c:
sys/i386/xen/exception.s:
sys/x86/include/segments.h:
	Reserve IDT vector 0x93 for the Xen event channel upcall
	interrupt handler.  On Hypervisors that support the direct
	vector callback feature, we can request that this vector be
	called directly by an injected HVM interrupt event, instead
	of a simulated PCI interrupt on the Xen platform PCI device.
	This avoids all of the overhead of dealing with the emulated
	I/O APIC and local APIC.  It also means that the Hypervisor
	can inject these events on any CPU, allowing upcalls for
	different ports to be handled in parallel.

sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
	Map Xen per-vcpu area during AP startup.

sys/amd64/include/intr_machdep.h:
sys/i386/include/intr_machdep.h:
	Increase the FreeBSD IRQ vector table to include space
	for event channel interrupt sources.

sys/amd64/include/pcpu.h:
sys/i386/include/pcpu.h:
	Remove Xen HVM per-cpu variable data.  These fields are now
	allocated via the dynamic per-cpu scheme.  See xen_intr.c
	for details.

sys/amd64/include/xen/hypercall.h:
sys/dev/xen/blkback/blkback.c:
sys/i386/include/xen/xenvar.h:
sys/i386/xen/clock.c:
sys/i386/xen/xen_machdep.c:
sys/xen/gnttab.c:
	Prefer FreeBSD primatives to Linux ones in Xen support code.

sys/amd64/include/xen/xen-os.h:
sys/i386/include/xen/xen-os.h:
sys/xen/xen-os.h:
sys/dev/xen/balloon/balloon.c:
sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/console/xencons_ring.c:
sys/dev/xen/control/control.c:
sys/dev/xen/netback/netback.c:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/xenpci/xenpci.c:
sys/i386/i386/machdep.c:
sys/i386/include/pmap.h:
sys/i386/include/xen/xenfunc.h:
sys/i386/isa/npx.c:
sys/i386/xen/clock.c:
sys/i386/xen/mp_machdep.c:
sys/i386/xen/mptable.c:
sys/i386/xen/xen_clock_util.c:
sys/i386/xen/xen_machdep.c:
sys/i386/xen/xen_rtc.c:
sys/xen/evtchn/evtchn_dev.c:
sys/xen/features.c:
sys/xen/gnttab.c:
sys/xen/gnttab.h:
sys/xen/hvm.h:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_if.m:
sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusvar.h:
sys/xen/xenstore/xenstore.c:
sys/xen/xenstore/xenstore_dev.c:
sys/xen/xenstore/xenstorevar.h:
	Pull common Xen OS support functions/settings into xen/xen-os.h.

sys/amd64/include/xen/xen-os.h:
sys/i386/include/xen/xen-os.h:
sys/xen/xen-os.h:
	Remove constants, macros, and functions unused in FreeBSD's Xen
	support.

sys/xen/xen-os.h:
sys/i386/xen/xen_machdep.c:
sys/x86/xen/hvm.c:
	Introduce new functions xen_domain(), xen_pv_domain(), and
	xen_hvm_domain().  These are used in favor of #ifdefs so that
	FreeBSD can dynamically detect and adapt to the presence of
	a hypervisor.  The goal is to have an HVM optimized GENERIC,
	but more is necessary before this is possible.

sys/amd64/amd64/machdep.c:
sys/dev/xen/xenpci/xenpcivar.h:
sys/dev/xen/xenpci/xenpci.c:
sys/x86/xen/hvm.c:
sys/sys/kernel.h:
	Refactor magic ioport, Hypercall table and Hypervisor shared
	information page setup, and move it to a dedicated HVM support
	module.

	HVM mode initialization is now triggered during the
	SI_SUB_HYPERVISOR phase of system startup.  This currently
	occurs just after the kernel VM is fully setup which is
	just enough infrastructure to allow the hypercall table
	and shared info page to be properly mapped.

sys/xen/hvm.h:
sys/x86/xen/hvm.c:
	Add definitions and a method for configuring Hypervisor event
	delievery via a direct vector callback.

sys/amd64/include/xen/xen-os.h:
sys/x86/xen/hvm.c:

sys/conf/files:
sys/conf/files.amd64:
sys/conf/files.i386:
	Adjust kernel build to reflect the refactoring of early
	Xen startup code and Xen interrupt services.

sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
sys/dev/xen/control/control.c:
sys/dev/xen/evtchn/evtchn_dev.c:
sys/dev/xen/netback/netback.c:
sys/dev/xen/netfront/netfront.c:
sys/xen/xenstore/xenstore.c:
sys/xen/evtchn/evtchn_dev.c:
sys/dev/xen/console/console.c:
sys/dev/xen/console/xencons_ring.c
	Adjust drivers to use new xen_intr_*() API.

sys/dev/xen/blkback/blkback.c:
	Since blkback defers all event handling to a taskqueue,
	convert this task queue to a "fast" taskqueue, and schedule
	it via an interrupt filter.  This avoids an unnecessary
	ithread context switch.

sys/xen/xenstore/xenstore.c:
	The xenstore driver is MPSAFE.  Indicate as much when
	registering its interrupt handler.

sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbusvar.h:
	Remove unused event channel APIs.

sys/xen/evtchn.h:
	Remove all kernel Xen interrupt service API definitions
	from this file.  It is now only used for structure and
	ioctl definitions related to the event channel userland
	device driver.

	Update the definitions in this file to match those from
	NetBSD.  Implementing this interface will be necessary for
	Dom0 support.

sys/xen/evtchn/evtchnvar.h:
	Add a header file for implemenation internal APIs related
	to managing event channels event delivery.  This is used
	to allow, for example, the event channel userland device
	driver to access low-level routines that typical kernel
	consumers of event channel services should never access.

sys/xen/interface/event_channel.h:
sys/xen/xen_intr.h:
	Standardize on the evtchn_port_t type for referring to
	an event channel port id.  In order to prevent low-level
	event channel APIs from leaking to kernel consumers who
	should not have access to this data, the type is defined
	twice: Once in the Xen provided event_channel.h, and again
	in xen/xen_intr.h.  The double declaration is protected by
	__XEN_EVTCHN_PORT_DEFINED__ to ensure it is never declared
	twice within a given compilation unit.

sys/xen/xen_intr.h:
sys/xen/evtchn/evtchn.c:
sys/x86/xen/xen_intr.c:
sys/dev/xen/xenpci/evtchn.c:
sys/dev/xen/xenpci/xenpcivar.h:
	New implementation of Xen interrupt services.  This is
	similar in many respects to the i386 PV implementation with
	the exception that events for bound to event channel ports
	(i.e. not IPI, virtual IRQ, or physical IRQ) are further
	optimized to avoid mask/unmask operations that aren't
	necessary for these edge triggered events.

	Stubs exist for supporting physical IRQ binding, but will
	need additional work before this implementation can be
	fully shared between PV and HVM.

sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
sys/i386/xen/mp_machdep.c
sys/x86/xen/hvm.c:
	Add support for placing vcpu_info into an arbritary memory
	page instead of using HYPERVISOR_shared_info->vcpu_info.
	This allows the creation of domains with more than 32 vcpus.

sys/i386/i386/machdep.c:
sys/i386/xen/clock.c:
sys/i386/xen/xen_machdep.c:
sys/i386/xen/exception.s:
	Add support for new event channle implementation.
Clarify confusions between atomic_t and bitmap.  Fix bitmap operations
accordingly.
Fix the incomplete conversion from atomic_t to long for test_bit().
Bump up the default timeouts for move commands in the ch(4) driver
to 15 minutes, and 5 minutes for things like READ ELEMENT STATUS.

This is needed to account for the worst case scenarios on at least
some Spectra Logic tape libraries.

Sponsored by:	Spectra Logic
MFC after:	3 days
Partially revert r254880.  The bitmap operations actually use long type now.
'u_long' is consistently spelled 'unsigned long' in this file.  Fix it.
Introduce a new, HVM compatible, paravirtualized timer driver for Xen.
Use this new driver for both PV and HVM instances.

This driver requires a Xen hypervisor that supports vector callbacks,
VCPUOP hypercalls, and reports that it has a "safe PV clock".

New timer driver:
Submitted by: will
Sponsored by: Spectra Logic Corporation

PV port to new driver, and bug fixes:
Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D

sys/dev/xen/timer/timer.c:
	- Register a PV timer device driver which (currently)
	  implements device_{identify,probe,attach} and stubs
	  device_detach.  The detach routine requires functionality
	  not provided by timecounters(4).  The suspend and resume
	  routines need additional work (due to Xen requiring that
	  the hypercalls be executed on the target VCPU), and aren't
	  needed for our purposes.

	- Make sure there can only be one device instance of this
	  driver, and that it only registers one eventtimers(4) and
	  one timecounters(4) device interface.  Make both interfaces
	  use PCPU data as needed.

	- Match, with a few style cleanups & API differences, the
	  Xen versions of the "fetch time" functions.

	- Document the magic scale_delta() better for the i386 version.

	- When registering the event timer, bind a separate event
	  channel for the timer VIRQ to the device's event timer
	  interrupt handler for each active VCPU.  Describe each
	  interrupt as "xen_et:c%d", so they can be identified per
	  CPU in "vmstat -i" or "show intrcnt" in KDB.

	- When scheduling a timer into the hypervisor, try up to
	  60 times if the hypervisor rejects the time as being in
	  the past.  In the common case, this retry shouldn't happen,
	  and if it does, it should only happen once.  This is
	  because the event timer advertises a minimum period of
	  100usec, which is only less than the usual hypercall round
	  trip time about 1 out of every 100 tries.  (Unlike other
	  similar drivers, this one actually checks whether the
	  hypervisor accepted the singleshot timer set hypercall.)

	- Implement a RTC PV clock based on the hypervisor wallclock.

sys/conf/files:
	- Add dev/xen/timer/timer.c if the kernel configuration
	  includes either the XEN or XENHVM options.

sys/conf/files.i386:
sys/i386/include/xen/xen_clock_util.h:
sys/i386/xen/clock.c:
sys/i386/xen/xen_clock_util.c:
sys/i386/xen/mp_machdep.c:
sys/i386/xen/xen_rtc.c:
	- Remove previous PV timer used in i386 XEN PV kernels, the
	  new timer introduced in this change is used instead (so
	  we share the same code between PVHVM and PV).

MFC after: 2 weeks
Add a routine for attaching an mbuf to a buffer with an external
refcount.  This one is willing to work with buffers that may already be
referenced.  MEXTADD/m_extadd are suitable only for the first attachment
to a cluster -- they initialize the refcount to 1.
- Fix LOCAL_MTREE so it properly handles multiple files and quotes
  its value into submakes

PR:		conf/179466
Submitted by:	Garrett Cooper <yaneurabeya@gmail.com>
Approved by:	bapt
MFC after:	2 weeks
Sponsored by:	EMC / Isilon Storage Division
Implement support for rx buffer packing.  Enable it by default for T5
cards.

This is a T4 and T5 chip feature which lets the chip deliver multiple
Ethernet frames in a single buffer.  This is more efficient within the
chip, in the driver, and reduces wastage of space in rx buffers.

- Always allocate rx buffers from the jumbop zone, no matter what the
  MTU is.  Do not use the normal cluster refcounting mechanism.
- Reserve space for an mbuf and a refcount in the cluster itself and let
  the chip DMA multiple frames in the rest.
- Use the embedded mbuf for the first frame and allocate mbufs on the
  fly for any additional frames delivered in the cluster.  Each of these
  mbufs has a reference on the underlying cluster.