- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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

MFC r256746:

Remove redundant redeclaration of gdtset in sys/xen/xen-os.h, to silence
a gcc warning.

Approved by: re (glebius)

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

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

Merge Xen PVHVM support into the GENERIC kernel config for both
amd64 and i386.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
MFC after: 2 weeks

sys/amd64/amd64/mp_machdep.c:
sys/amd64/include/cpu.h:
sys/i386/i386/mp_machdep.c:
sys/i386/include/cpu.h:
- Introduce two new CPU hooks for initialization and resume
purposes. This allows us to get rid of the XENHVM ifdefs in
mp_machdep, and also sets some hooks into common code that can be
used by other hypervisor implementations.

sys/amd64/conf/XENHVM:
sys/i386/conf/XENHVM:
- Remove these configs now that GENERIC has builtin support for Xen
HVM.

sys/kern/subr_smp.c:
- Make sure there are no pending IPIs when suspending a system.

sys/x86/xen/hvm.c:
- Add cpu init and resume vectors that are called from mp_machdep
using the new hooks.
- Only clear the vcpu_info mapping data on resume. It is already
clear for the BSP on a cold boot and is set correctly as APs
are started.
- Gate xen_hvm_init_cpu only to systems running under Xen.

sys/x86/xen/xen_intr.c:
- Gate the setup of event channels only to systems running under Xen.

Add support for suspend/resume/migration operations when running as a
Xen PVHVM guest.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Reviewed by: gibbs
Approved by: re (blanket Xen)
MFC after: 2 weeks

sys/amd64/amd64/mp_machdep.c:
sys/i386/i386/mp_machdep.c:
- Make sure that are no MMU related IPIs pending on migration.
- Reset pending IPI_BITMAP on resume.
- Init vcpu_info on resume.

sys/amd64/include/intr_machdep.h:
sys/i386/include/intr_machdep.h:
sys/x86/acpica/acpi_wakeup.c:
sys/x86/x86/intr_machdep.c:
sys/x86/isa/atpic.c:
sys/x86/x86/io_apic.c:
sys/x86/x86/local_apic.c:
- Add a "suspend_cancelled" parameter to pic_resume(). For the
Xen PIC, restoration of interrupt services differs between
the aborted suspend and normal resume cases, so we must provide
this information.

sys/dev/acpica/acpi_timer.c:
sys/dev/xen/timer/timer.c:
sys/timetc.h:
- Don't swap out "suspend safe" timers across a suspend/resume
cycle. This includes the Xen PV and ACPI timers.

sys/dev/xen/control/control.c:
- Perform proper suspend/resume process for PVHVM:
- Suspend all APs before going into suspension, this allows us
to reset the vcpu_info on resume for each AP.
- Reset shared info page and callback on resume.

sys/dev/xen/timer/timer.c:
- Implement suspend/resume support for the PV timer. Since FreeBSD
doesn't perform a per-cpu resume of the timer, we need to call
smp_rendezvous in order to correctly resume the timer on each CPU.

sys/dev/xen/xenpci/xenpci.c:
- Don't reset the PCI interrupt on each suspend/resume.

sys/kern/subr_smp.c:
- When suspending a PVHVM domain make sure there are no MMU IPIs
in-flight, or we will get a lockup on resume due to the fact that
pending event channels are not carried over on migration.
- Implement a generic version of restart_cpus that can be used by
suspended and stopped cpus.

sys/x86/xen/hvm.c:
- Implement resume support for the hypercall page and shared info.
- Clear vcpu_info so it can be reset by APs when resuming from
suspension.

sys/dev/xen/xenpci/xenpci.c:
sys/x86/xen/hvm.c:
sys/x86/xen/xen_intr.c:
- Support UP kernel configurations.

sys/x86/xen/xen_intr.c:
- Properly rebind per-cpus VIRQs and IPIs on resume.

Implement PV IPIs for PVHVM guests and further converge PV and HVM
IPI implmementations.

Submitted by: Roger Pau Monné
Sponsored by: Citrix Systems R&D
Submitted by: gibbs (misc cleanup, table driven config)
Reviewed by: gibbs
MFC after: 2 weeks

sys/amd64/include/cpufunc.h:
sys/amd64/amd64/pmap.c:
Move invltlb_globpcid() into cpufunc.h so that it can be
used by the Xen HVM version of tlb shootdown IPI handlers.

sys/x86/xen/xen_intr.c:
sys/xen/xen_intr.h:
Rename xen_intr_bind_ipi() to xen_intr_alloc_and_bind_ipi(),
and remove the ipi vector parameter. This api allocates
an event channel port that can be used for ipi services,
but knows nothing of the actual ipi for which that port
will be used. Removing the unused argument and cleaning
up the comments surrounding its declaration helps clarify
its actual role.

sys/amd64/amd64/mp_machdep.c:
sys/amd64/include/cpu.h:
sys/i386/i386/mp_machdep.c:
sys/i386/include/cpu.h:
Implement a generic framework for amd64 and i386 that allows
the implementation of certain CPU management functions to
be selected at runtime. Currently this is only used for
the ipi send function, which we optimize for Xen when running
on a Xen hypervisor, but can easily be expanded to support
more operations.

sys/x86/xen/hvm.c:
Implement Xen PV IPI handlers and operations, replacing native
send IPI.

sys/amd64/include/pcpu.h:
sys/i386/include/pcpu.h:
sys/i386/include/smp.h:
Remove NR_VIRQS and NR_IPIS from FreeBSD headers. NR_VIRQS
is defined already for us in the xen interface files.
NR_IPIS is only needed in one file per Xen platform and is
easily inferred by the IPI vector table that is defined in
those files.

sys/i386/xen/mp_machdep.c:
Restructure to more closely match the HVM implementation by
performing table driven IPI setup.

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.

Replace kernel virtual address space allocation with vmem. This provides
transparent layering and better fragmentation.

- Normalize functions that allocate memory to use kmem_*
- Those that allocate address space are named kva_*
- Those that operate on maps are named kmap_*
- Implement recursive allocation handling for kmem_arena in vmem.

Reviewed by: alc
Tested by: pho
Sponsored by: EMC / Isilon Storage Division

Adjust i386 Xen PV support for updated Xen interface files.

sys/i386/include/xen/xenvar.h:
sys/i386/xen/xen_machdep.c:
sys/xen/interface/foreign/structs.py:
sys/xen/evtchn/evtchn.c:
MAX_VIRT_CPUS => XEN_LEGACY_MAX_VCPUS

Submitted by: Roger Pau Monné
Reviewed by: gibbs

Upgrade Xen interface headers to Xen 4.2.1.

Move FreeBSD from interface version 0x00030204 to 0x00030208.
Updates are required to our grant table implementation before we
can bump this further.

sys/xen/hvm.h:
Replace the implementation of hvm_get_parameter(), formerly located
in sys/xen/interface/hvm/params.h. Linux has a similar file which
primarily stores this function.

sys/xen/xenstore/xenstore.c:
Include new xen/hvm.h header file to get hvm_get_parameter().

sys/amd64/include/xen/xen-os.h:
sys/i386/include/xen/xen-os.h:
Correctly protect function definition and variables from being
included into assembly files in xen-os.h

Xen memory barriers are now prefixed with "xen_" to avoid conflicts
with OS native primatives. Define Xen memory barriers in terms of
the native FreeBSD primatives.

Sponsored by: Spectra Logic Corporation
Reviewed by: Roger Pau Monné
Tested by: Roger Pau Monné
Obtained from: Roger Pau Monné (bug fixes)

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

xenstore/xenstore.c:
Prevent access to invalid memory region when listing an empty
directory in the XenStore.

Reported by: Bei Guan
MFC after: 1 week

Move the corresponding MTX_SYSINIT() next to their struct mtx declaration
to make their relationship more obvious as done with the other such mutexs.

Make xen python scripts work with python3

Approved by: cperciva
MFC after: 3 days

blkif interface comment cleanups. No functional changes

sys/xen/interface/io/blkif.h:
o Insert space in "Red Hat".
o Fix typo "discard-aligment" -> "discard-alignment"
o Fix typo "unamp" -> "unmap"
o Fix typo "formated" -> "formatted"
o Clarify the text for "params".
o Clarify the text for "sector-size".
o Clarify the text for "max-requests" in the backend section.

Fix "_" vs. "-" typo in a comment. No functional changes.

Enhance documentation, improve interoperability, and fix defects in
FreeBSD's front and back Xen blkif interface drivers.

sys/dev/xen/blkfront/block.h:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
Replace FreeBSD specific multi-page ring impelementation with
support for both the Citrix and Amazon/RedHat versions of this
extension.

sys/dev/xen/blkfront/blkfront.c:
o Add a per-instance sysctl tree that exposes all negotiated
transport parameters (ring pages, max number of requests,
max request size, max number of segments).
o In blkfront_vdevice_to_unit() add a missing return statement
so that we properly identify the unit number for high numbered
xvd devices.

sys/dev/xen/blkback/blkback.c:
o Add static dtrace probes for several events in this driver.
o Defer connection shutdown processing until the front-end
enters the closed state. This avoids prematurely tearing
down the connection when buggy front-ends transition to the
closing state, even though the device is open and they
veto the close request from the tool stack.
o Add nodes for maximum request size and the number of active
ring pages to the exising, per-instance, sysctl tree.
o Miscelaneous style cleanup.

sys/xen/interface/io/blkif.h:
o Add extensive documentation of the XenStore nodes used to
implement the blkif interface.
o Document the startup sequence between a front and back driver.
o Add structures and documenatation for the "discard" feature
(AKA Trim).
o Cleanup some definitions related to FreeBSD's request
number/size/segment-limit extension.

sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
sys/xen/xenbus/xenbusvar.h:
Add the convenience function xenbus_get_otherend_state() and
use it to simplify some logic in both block-front and block-back.

MFC after: 1 day

Add the GSO prefix descriptor define.

MFC after: 3 days

Xen netback driver rewrite.

share/man/man4/Makefile,
share/man/man4/xnb.4,
sys/dev/xen/netback/netback.c,
sys/dev/xen/netback/netback_unit_tests.c:

Rewrote the netback driver for xen to attach properly via newbus
and work properly in both HVM and PVM mode (only HVM is tested).
Works with the in-tree FreeBSD netfront driver or the Windows
netfront driver from SuSE. Has not been extensively tested with
a Linux netfront driver. Does not implement LRO, TSO, or
polling. Includes unit tests that may be run through sysctl
after compiling with XNB_DEBUG defined.

sys/dev/xen/blkback/blkback.c,
sys/xen/interface/io/netif.h:

Comment elaboration.

sys/kern/uipc_mbuf.c:

Fix page fault in kernel mode when calling m_print() on a
null mbuf. Since m_print() is only used for debugging, there
are no performance concerns for extra error checking code.

sys/kern/subr_scanf.c:

Add the "hh" and "ll" width specifiers from C99 to scanf().
A few callers were already using "ll" even though scanf()
was handling it as "l".

Submitted by: Alan Somers <alans@spectralogic.com>
Submitted by: John Suykerbuyk <johns@spectralogic.com>
Sponsored by: Spectra Logic
MFC after: 1 week
Reviewed by: ken

s/timout/timeout

Use C99 initializers for members of evtchn_devsw.

Submitted by: arundel

- There's no need to overwrite the default device method with the default
one. Interestingly, these are actually the default for quite some time
(bus_generic_driver_added(9) since r52045 and bus_generic_print_child(9)
since r52045) but even recently added device drivers do this unnecessarily.
Discussed with: jhb, marcel
- While at it, use DEVMETHOD_END.
Discussed with: jhb
- Also while at it, use __FBSDID.

Properly handle suspend/resume events in the Xen device
framework.

Sponsored by: BQ Internet

sys/xen/xenbus/xenbusb.c:
o In xenbusb_resume(), publish the state transition of the
resuming device into XenbusStateIntiailising so that the
remote peer can see it. Recording the state locally is
not sufficient to trigger a re-connect sequence.
o In xenbusb_resume(), defer new-bus resume processing until
after the remote peer's XenStore address has been updated.
The drivers may need to refer to this information during
resume processing.

sys/xen/xenbus/xenbusb_back.c:
sys/xen/xenbus/xenbusb_front.c:
Register xenbusb_resume() rather than bus_generic_resume()
as the handler for device_resume events.

sys/xen/xenstore/xenstore.c:
o Fix grammer in a comment.
o In xs_suspend(), pass suspend events on to the child
devices (e.g. xenbusb_front/back, that are attached
to the XenStore.

Approved by: re
MFC after: 1 week

Monitor and emit events for XenStore changes to XenBus trees
of the devices we manage. These changes can be due to writes
we make ourselves or due to changes made by the control domain.
The goal of these changes is to insure that all state transitions
can be detected regardless of their source and to allow common
device policies (e.g. "onlined" backend devices) to be centralized
in the XenBus bus code.

sys/xen/xenbus/xenbusvar.h:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_if.m:
Add a new method for XenBus drivers "localend_changed".
This method is invoked whenever a write is detected to
a device's XenBus tree. The default implementation of
this method is a no-op.

sys/xen/xenbus/xenbus_if.m:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkback/blkback.c:
Change the signature of the "otherend_changed" method.
This notification cannot fail, so it should return void.

sys/xen/xenbus/xenbusb_back.c:
Add "online" device handling to the XenBus Back Bus
support code. An online backend device remains active
after a front-end detaches as a reconnect is expected
to occur in the near future.

sys/xen/interface/io/xenbus.h:
Add comment block further explaining the meaning and
driver responsibilities associated with the XenBus
Closed state.

sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
sys/xen/xenbus/xenbusb_back.c:
sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusb_if.m:
o Register a XenStore watch against the local XenBus tree
for all devices.
o Cache the string length of the path to our local tree.
o Allow the xenbus front and back drivers to hook/filter both
local and otherend watch processing.
o Update the device ivar version of "state" when we detect
a XenStore update of that node.

sys/dev/xen/control/control.c:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
sys/xen/xenbus/xenbusvar.h:
sys/xen/xenstore/xenstorevar.h:
Allow clients of the XenStore watch mechanism to attach
a single uintptr_t worth of client data to the watch.
This removes the need to carefully place client watch
data within enclosing objects so that a cast or offsetof
calculation can be used to convert from watch to enclosing
object.

Sponsored by: Spectra Logic Corporation
MFC after: 1 week

Fix a few more SYSCTL_PROC() that were missing a CTLFLAG type specifier.

Add xenpic_dynirq_disable_intr and set it as the .pic_disable_intr method
for xenpic_dynirq_template. This fixes a panic when a virtual disk is
removed, since that results in an interrupt channel being disabled and
NULL isn't very good function for disabling interrupts.

We should probably have a xenpic_pirq_disable_intr as well; I'm not adding
that here because (a) I'm not sure what uses pirqs so I don't have a test
case, and (b) the xenpic_pirq_enable_intr code is significantly more
complex than the xenpic_dynirq_enable_intr code, so I'm not sure what
should go into a xenpic_pirq_disable_intr routine.

PR: kern/153511
MFC after: 3 days

Fix a typo in a comment.

Noticed by: Attila Nagy <bra@fsn.hu>

Remove spurious printf left over from debugging our XenStore support.

Postpone the unmasking of event channels (aka. interrupts) until after
the interrupt handlers have been registered. NULL isn't a very good
interrupt handler.

Improve the Xen para-virtualized device infrastructure of FreeBSD:

o Add support for backend devices (e.g. blkback)
o Implement extensions to the Xen para-virtualized block API to allow
for larger and more outstanding I/Os.
o Import a completely rewritten block back driver with support for fronting
I/O to both raw devices and files.
o General cleanup and documentation of the XenBus and XenStore support code.
o Robustness and performance updates for the block front driver.
o Fixes to the netfront driver.

Sponsored by: Spectra Logic Corporation

sys/xen/xenbus/init.txt:
Deleted: This file explains the Linux method for XenBus device
enumeration and thus does not apply to FreeBSD's NewBus approach.

sys/xen/xenbus/xenbus_probe_backend.c:
Deleted: Linux version of backend XenBus service routines. It
was never ported to FreeBSD. See xenbusb.c, xenbusb_if.m,
xenbusb_front.c xenbusb_back.c for details of FreeBSD's XenBus
support.

sys/xen/xenbus/xenbusvar.h:
sys/xen/xenbus/xenbus_xs.c:
sys/xen/xenbus/xenbus_comms.c:
sys/xen/xenbus/xenbus_comms.h:
sys/xen/xenstore/xenstorevar.h:
sys/xen/xenstore/xenstore.c:
Split XenStore into its own tree. XenBus is a software layer built
on top of XenStore. The old arrangement and the naming of some
structures and functions blurred these lines making it difficult to
discern what services are provided by which layer and at what times
these services are available (e.g. during system startup and shutdown).

sys/xen/xenbus/xenbus_client.c:
sys/xen/xenbus/xenbus.c:
sys/xen/xenbus/xenbus_probe.c:
sys/xen/xenbus/xenbusb.c:
sys/xen/xenbus/xenbusb.h:
Split up XenBus code into methods available for use by client
drivers (xenbus.c) and code used by the XenBus "bus code" to
enumerate, attach, detach, and service bus drivers.

sys/xen/reboot.c:
sys/dev/xen/control/control.c:
Add a XenBus front driver for handling shutdown, reboot, suspend, and
resume events published in the XenStore. Move all PV suspend/reboot
support from reboot.c into this driver.

sys/xen/blkif.h:
New file from Xen vendor with macros and structures used by
a block back driver to service requests from a VM running a
different ABI (e.g. amd64 back with i386 front).

sys/conf/files:
Adjust kernel build spec for new XenBus/XenStore layout and added
Xen functionality.

sys/dev/xen/balloon/balloon.c:
sys/dev/xen/netfront/netfront.c:
sys/dev/xen/blkfront/blkfront.c:
sys/xen/xenbus/...
sys/xen/xenstore/...
o Rename XenStore APIs and structures from xenbus_* to xs_*.
o Adjust to use of M_XENBUS and M_XENSTORE malloc types for allocation
of objects returned by these APIs.
o Adjust for changes in the bus interface for Xen drivers.

sys/xen/xenbus/...
sys/xen/xenstore/...
Add Doxygen comments for these interfaces and the code that
implements them.

sys/dev/xen/blkback/blkback.c:
o Rewrite the Block Back driver to attach properly via newbus,
operate correctly in both PV and HVM mode regardless of domain
(e.g. can be in a DOM other than 0), and to deal with the latest
metadata available in XenStore for block devices.

o Allow users to specify a file as a backend to blkback, in addition
to character devices. Use the namei lookup of the backend path
to automatically configure, based on file type, the appropriate
backend method.

The current implementation is limited to a single outstanding I/O
at a time to file backed storage.

sys/dev/xen/blkback/blkback.c:
sys/xen/interface/io/blkif.h:
sys/xen/blkif.h:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
Extend the Xen blkif API: Negotiable request size and number of
requests.

This change extends the information recorded in the XenStore
allowing block front/back devices to negotiate for optimal I/O
parameters. This has been achieved without sacrificing backward
compatibility with drivers that are unaware of these protocol
enhancements. The extensions center around the connection protocol
which now includes these additions:

o The back-end device publishes its maximum supported values for,
request I/O size, the number of page segments that can be
associated with a request, the maximum number of requests that
can be concurrently active, and the maximum number of pages that
can be in the shared request ring. These values are published
before the back-end enters the XenbusStateInitWait state.

o The front-end waits for the back-end to enter either the InitWait
or Initialize state. At this point, the front end limits it's
own capabilities to the lesser of the values it finds published
by the backend, it's own maximums, or, should any back-end data
be missing in the store, the values supported by the original
protocol. It then initializes it's internal data structures
including allocation of the shared ring, publishes its maximum
capabilities to the XenStore and transitions to the Initialized
state.

o The back-end waits for the front-end to enter the Initalized
state. At this point, the back end limits it's own capabilities
to the lesser of the values it finds published by the frontend,
it's own maximums, or, should any front-end data be missing in
the store, the values supported by the original protocol. It
then initializes it's internal data structures, attaches to the
shared ring and transitions to the Connected state.

o The front-end waits for the back-end to enter the Connnected
state, transitions itself to the connected state, and can
commence I/O.

Although an updated front-end driver must be aware of the back-end's
InitWait state, the back-end has been coded such that it can
tolerate a front-end that skips this step and transitions directly
to the Initialized state without waiting for the back-end.

sys/xen/interface/io/blkif.h:
o Increase BLKIF_MAX_SEGMENTS_PER_REQUEST to 255. This is
the maximum number possible without changing the blkif
request header structure (nr_segs is a uint8_t).

o Add two new constants:
BLKIF_MAX_SEGMENTS_PER_HEADER_BLOCK, and
BLKIF_MAX_SEGMENTS_PER_SEGMENT_BLOCK. These respectively
indicate the number of segments that can fit in the first
ring-buffer entry of a request, and for each subsequent
(sg element only) ring-buffer entry associated with the
"header" ring-buffer entry of the request.

o Add the blkif_request_segment_t typedef for segment
elements.

o Add the BLKRING_GET_SG_REQUEST() macro which wraps the
RING_GET_REQUEST() macro and returns a properly cast
pointer to an array of blkif_request_segment_ts.

o Add the BLKIF_SEGS_TO_BLOCKS() macro which calculates the
number of ring entries that will be consumed by a blkif
request with the given number of segments.

sys/xen/blkif.h:
o Update for changes in interface/io/blkif.h macros.

o Update the BLKIF_MAX_RING_REQUESTS() macro to take the
ring size as an argument to allow this calculation on
multi-page rings.

o Add a companion macro to BLKIF_MAX_RING_REQUESTS(),
BLKIF_RING_PAGES(). This macro determines the number of
ring pages required in order to support a ring with the
supplied number of request blocks.

sys/dev/xen/blkback/blkback.c:
sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
o Negotiate with the other-end with the following limits:
Reqeust Size: MAXPHYS
Max Segments: (MAXPHYS/PAGE_SIZE) + 1
Max Requests: 256
Max Ring Pages: Sufficient to support Max Requests with
Max Segments.

o Dynamically allocate request pools and segemnts-per-request.

o Update ring allocation/attachment code to support a
multi-page shared ring.

o Update routines that access the shared ring to handle
multi-block requests.

sys/dev/xen/blkfront/blkfront.c:
o Track blkfront allocations in a blkfront driver specific
malloc pool.

o Strip out XenStore transaction retry logic in the
connection code. Transactions only need to be used when
the update to multiple XenStore nodes must be atomic.
That is not the case here.

o Fully disable blkif_resume() until it can be fixed
properly (it didn't work before this change).

o Destroy bus-dma objects during device instance tear-down.

o Properly handle backend devices with powef-of-2 sector
sizes larger than 512b.

sys/dev/xen/blkback/blkback.c:
Advertise support for and implement the BLKIF_OP_WRITE_BARRIER
and BLKIF_OP_FLUSH_DISKCACHE blkif opcodes using BIO_FLUSH and
the BIO_ORDERED attribute of bios.

sys/dev/xen/blkfront/blkfront.c:
sys/dev/xen/blkfront/block.h:
Fix various bugs in blkfront.

o gnttab_alloc_grant_references() returns 0 for success and
non-zero for failure. The check for < 0 is a leftover
Linuxism.

o When we negotiate with blkback and have to reduce some of our
capabilities, print out the original and reduced capability before
changing the local capability. So the user now gets the correct
information.

o Fix blkif_restart_queue_callback() formatting. Make sure we hold
the mutex in that function before calling xb_startio().

o Fix a couple of KASSERT()s.

o Fix a check in the xb_remove_* macro to be a little more specific.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
Define GNTTAB_LIST_END publicly as GRANT_REF_INVALID.

sys/dev/xen/netfront/netfront.c:
Use GRANT_REF_INVALID instead of driver private definitions of the
same constant.

sys/xen/gnttab.h:
sys/xen/gnttab.c:
Add the gnttab_end_foreign_access_references() API.

This API allows a client to batch the release of an array of grant
references, instead of coding a private for loop. The implementation
takes advantage of this batching to reduce lock overhead to one
acquisition and release per-batch instead of per-freed grant reference.

While here, reduce the duration the gnttab_list_lock is held during
gnttab_free_grant_references() operations. The search to find the
tail of the incoming free list does not rely on global state and so
can be performed without holding the lock.

sys/dev/xen/xenpci/evtchn.c:
sys/dev/xen/evtchn/evtchn.c:
sys/xen/xen_intr.h:
o Implement the bind_interdomain_evtchn_to_irqhandler API for HVM mode.
This allows an HVM domain to serve back end devices to other domains.
This API is already implemented for PV mode.

o Synchronize the API between HVM and PV.

sys/dev/xen/xenpci/xenpci.c:
o Scan the full region of CPUID space in which the Xen VMM interface
may be implemented. On systems using SuSE as a Dom0 where the
Viridian API is also exported, the VMM interface is above the region
we used to search.

o Pass through bus_alloc_resource() calls so that XenBus drivers
attaching on an HVM system can allocate unused physical address
space from the nexus. The block back driver makes use of this
facility.

sys/i386/xen/xen_machdep.c:
Use the correct type for accessing the statically mapped xenstore
metadata.

sys/xen/interface/hvm/params.h:
sys/xen/xenstore/xenstore.c:
Move hvm_get_parameter() to the correct global header file instead
of as a private method to the XenStore.

sys/xen/interface/io/protocols.h:
Sync with vendor.

sys/xeninterface/io/ring.h:
Add macro for calculating the number of ring pages needed for an N
deep ring.

To avoid duplication within the macros, create and use the new
__RING_HEADER_SIZE() macro. This macro calculates the size of the
ring book keeping struct (producer/consumer indexes, etc.) that
resides at the head of the ring.

Add the __RING_PAGES() macro which calculates the number of shared
ring pages required to support a ring with the given number of
requests.

These APIs are used to support the multi-page ring version of the
Xen block API.

sys/xeninterface/io/xenbus.h:
Add Comments.

sys/xen/xenbus/...
o Refactor the FreeBSD XenBus support code to allow for both front and
backend device attachments.

o Make use of new config_intr_hook capabilities to allow front and back
devices to be probed/attached in parallel.

o Fix bugs in probe/attach state machine that could cause the system to
hang when confronted with a failure either in the local domain or in
a remote domain to which one of our driver instances is attaching.

o Publish all required state to the XenStore on device detach and
failure. The majority of the missing functionality was for serving
as a back end since the typical "hot-plug" scripts in Dom0 don't
handle the case of cleaning up for a "service domain" that is not
itself.

o Add dynamic sysctl nodes exposing the generic ivars of
XenBus devices.

o Add doxygen style comments to the majority of the code.

o Cleanup types, formatting, etc.

sys/xen/xenbus/xenbusb.c:
Common code used by both front and back XenBus busses.

sys/xen/xenbus/xenbusb_if.m:
Method definitions for a XenBus bus.

sys/xen/xenbus/xenbusb_front.c:
sys/xen/xenbus/xenbusb_back.c:
XenBus bus specialization for front and back devices.

MFC after: 1 month

don't hold spin lock across free

Remove extraneous semicolons, no functional changes.

Submitted by: Marc Balmer <marc@msys.ch>
MFC after: 1 week

Correct bug introduced while purging the -ERRNO Linuxism from the
grant table API. Valid grant refs are in the range of positive 32bit
integers. ENOSPACE, being 29, is also a positive integer. Return
GNTTAB_LIST_END (-1) instead when gnttab_claim_grant_reference() fails.

Temporarily revert the new-bus locking for 8.0 release. It will be
reintroduced after HEAD is reopened for commits by re@.

Approved by: re (kib), attilio

Purge mergeinfo in sys/ that is either empty or a subset of the parent
mergeinfo on sys/ itself.

Approved by: re (mergeinfo blanket)

Make the newbus subsystem Giant free by adding the new newbus sxlock.
The newbus lock is responsible for protecting newbus internIal structures,
device states and devclass flags. It is necessary to hold it when all
such datas are accessed. For the other operations, softc locking should
ensure enough protection to avoid races.

Newbus lock is automatically held when virtual operations on the device
and bus are invoked when loading the driver or when the suspend/resume
take place. For other 'spourious' operations trying to access/modify
the newbus topology, newbus lock needs to be automatically acquired and
dropped.

For the moment Giant is also acquired in some key point (modules subsystem)
in order to avoid problems before the 8.0 release as module handlers could
make assumptions about it. This Giant locking should go just after
the release happens.

Please keep in mind that the public interface can be expanded in order
to provide more support, if there are really necessities at some point
and also some bugs could arise as long as the patch needs a bit of
further testing.

Bump __FreeBSD_version in order to reflect the newbus lock introduction.

Reviewed by: ed, hps, jhb, imp, mav, scottl
No answer by: ariff, thompsa, yongari
Tested by: pho,
G. Trematerra <giovanni dot trematerra at gmail dot com>,
Brandon Gooch <jamesbrandongooch at gmail dot com>
Sponsored by: Yahoo! Incorporated
Approved by: re (ksmith)

Catch up with r195249, "Improve the handling of cpuset with interrupts."
Specifically, update the return type of xenpic_assign_cpu() so that this
file compiles again.

Approved by: re (kib)

Make ipi_cpu() function as intended.

IPI's in Xen are implemented through hypervisor event channels.
The MP code creates a pair of IRQs for each base IPI per CPU
(one for IPI function dispatch calls, one for IPI bitmap dispatch calls.)
Using PCPU_GET() was returning the IRQ of the IPI handler for the
current CPU; thus calls to ipi_cpu() were sending itself a message.
Instead, looking up the IPI in the target CPU ipi-to-irq map is needed.

Note: This doesn't fix Xen SMP (far from it!) but it at least
sends IPI's to the right places. Next - sending IPIs..

PR: 135069

Don't call the watch callback if its NULL.

I'm not sure what series of events is leading up to this watch event
being received with no callback info and it should be investigated.
I'm triggering it somehow by registering an RTC device (which will
show up in a subsequent commit.)

Remove bogus prop

Remove pointeless mergeinfo that crept in from r190633.

Implement an ipfw action to reassemble ip packets: reass.

Fix the Xen build for i386 PV mode.

Integrate user/mav/ata branch:

Add ch_suspend/ch_resume methods for PCI controllers and implement them
for AHCI. Refactor AHCI channel initialization according to it.

Fix Port Multipliers operation. It is far from perfect yet, but works now.
Tested with JMicron JMB363 AHCI + SiI 3726 PMP pair.
Previous version was also tested with SiI 4726 PMP.

Hardware sponsored by: Vitsch Electronics / VEHosting.nl

Merge in support for Xen HVM on amd64 architecture.

merge 186535, 186537, and 186538 from releng_7_xen

Log:
- merge in latest xenbus from dfr's xenhvm
- fix race condition in xs_read_reply by converting tsleep to mtx_sleep

Log:
unmask evtchn in bind_{virq, ipi}_to_irq

Log:
- remove code for handling case of not being able to sleep
- eliminate tsleep - make sleeps atomic

Integrate 185578 from dfr
Use newbus to managed devices

merge fix for boot-time hang on centos' xen

Fix evtchn initialization on SMP

Fix IPI support

move ipi_pcpu to evtchn.c

Update xen/interface includes to the latest in mercurial

MFC after: 1 month

partial update to interface headers to 3.2

MFC after: 1 month

- add more debug cruft to xenbus
- probe backend
- separate probing from initialization
- add xenbus_strstate
- replace pause with tsleep (which should probably be cv_wait)

Check for watch events when doing inline message processing

MFC after: 1 month

Xen 3.2 now interleaves watch events with regular message notifications.
More graciously handle processing messages and watch events inline prior
to threads being up and running.

MFC after: 1 month

avoid evtchn_init name collision in gdb

MFC after: 1 month

Make sure we don't lose the most significant bits of the frame number on PAE or 64-bit

MFC after: 1 month

Import check for xen features.

MFC after: 1 month

Compile fixes for xen build.

MFC after: 1 month.

Import OS interfaces to Xen services.

MFC after: 2 weeks