Fixed MSI interrupt allocation and handling.
Fixed a DMA mapping leak that occurs when defragmenting packet chains.

Approved by:	davidch (mentor)
MFC after:	1 week
amd64/i386: switch IPI handlers to C code.

Move asm IPIs handlers to C code, so both Xen and native IPI handlers
share the same code.

Reviewed by: jhb
Approved by: gibbs
Sponsored by: Citrix Systems R&D

amd64/amd64/apic_vector.S:
i386/i386/apic_vector.s:
 - Remove asm coded IPI handlers and instead call the newly introduced
   C variants.

amd64/amd64/mp_machdep.c:
i386/i386/mp_machdep.c:
 - Add C coded clones to the asm IPI handlers (moved from
   x86/xen/hvm.c).

i386/include/smp.h:
amd64/include/smp.h:
 - Add prototypes for the C IPI handlers.

x86/xen/hvm.c:
 - Move the C IPI handlers to mp_machdep and call those in the Xen IPI
   handlers.

i386/xen/mp_machdep.c:
 - Add dummy IPI handlers to the i386 Xen PV port (this port doesn't
   support SMP).
xen: add PV/PVH kernel entry point

Add the PV/PVH entry point and the low level functions for PVH
early initialization.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

amd64/amd64/genassym.c:
 - Add __FreeBSD_version define to assym.s so it can be used for the
   Xen notes.

amd64/amd64/locore.S:
 - Make bootstack global so it can be used from Xen kernel entry
   point.

amd64/amd64/xen-locore.S:
 - Add Xen notes to the kernel.
 - Add the Xen PV entry point, that is going to call hammer_time_xen.

amd64/include/asmacros.h:
 - Add ELFNOTE macros.

i386/xen/xen_machdep.c:
 - Define HYPERVISOR_start_info for the XEN i386 PV port, which is
   going to be used in some shared code between PV and PVH.

x86/xen/hvm.c:
 - Define HYPERVISOR_start_info for the PVH port.

x86/xen/pv.c:
 - Introduce hammer_time_xen which is going to perform early setup for
   Xen PVH:
    - Setup shared Xen variables start_info, shared_info and
      xen_store.
    - Set guest type.
    - Create initial page tables as FreeBSD expects to find them.
    - Call into native init function (hammer_time).

xen/xen-os.h:
 - Declare HYPERVISOR_start_info.

conf/files.amd64:
 - Add amd64/amd64/locore.S and x86/xen/pv.c to the list of files.
xen: add macro to detect if running as Dom0

Approved by: gibbs
Sponsored by: Citrix Systems R&D

xen/xen-os.h:
 - Add macro to detect if running as Dom0.
xen: add and enable Xen console for PVH guests

This adds and enables the PV console used on XEN kernels to
GENERIC/XENHVM kernels in order for it to be used on PVH.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

dev/xen/console/console.c:
 - Define console_page.
 - Move xc_printf debug function from i386 XEN code to generic console
   code.
 - Rework xc_printf.
 - Use xen_initial_domain instead of open-coded checks for Dom0.
 - Gate the attach of the PV console to PV(H) guests.

dev/xen/console/xencons_ring.c:
 - Allow the PV Xen console to output earlier by directly signaling
   the event channel in start_info if the event channel is not yet
   initialized.
 - Use HYPERVISOR_start_info instead of xen_start_info.

i386/include/xen/xen-os.h:
 - Remove prototype for xc_printf since it's now declared in global
   xen-os.h

i386/xen/xen_machdep.c:
 - Remove previous version of xc_printf.
 - Remove definition of console_page (now it's defined in the console
   itself).
 - Fix some printf formatting errors.

x86/xen/pv.c:
 - Add some early boot debug messages using xc_printf.
 - Set console_page based on the value passed in start_info.

xen/xen-os.h:
 - Declare console_page and add prototype for xc_printf.
howto_names: unify declaration

Approved by: gibbs
Sponsored by: Citrix Systems R&D

boot/i386/efi/bootinfo.c:
boot/i386/libi386/bootinfo.c:
boot/ia64/common/bootinfo.c:
boot/powerpc/ofw/metadata.c:
boot/powerpc/ps3/metadata.c:
boot/sparc64/loader/metadata.c:
boot/uboot/common/metadata.c:
boot/userboot/userboot/bootinfo.c:
i386/xen/xen_machdep.c:
 - Include sys/boot.h
 - Remove custom definition of howto_names.

sys/boot.h:
 - Define howto_names.

x86/xen/pv.c:
 - Include sys/boot.h
amd64: introduce hook for custom preload metadata parsers

Add hooks to amd64 in order to have diverging implementations, since
on Xen PV the metadata is passed to the kernel in a different form.

Approbed by: gibbs
Sponsored by: Citrix Systems R&D

amd64/amd64/machdep.c:
 - Define init_ops for native.
 - Put native code inside of native_parse_preload_data hook.
 - Call the parse_preload_data in order to fill the metadata info.

x86/include/init.h:
 - Declare the init_ops struct.

x86/xen/pv.c:
 - Declare xen_init_ops that contains the Xen PV implementation of
   init_ops.
 - Implement the parse_preload_data for Xen PVH, the info is fetched
   from HYPERVISOR_start_info->cmd_line as provided by Xen.
xen: rework xen timer so it can be used early in boot process

This should not introduce any functional change, and makes the
functions suitable to be called before we have actually mapped the
vcpu_info struct on a per-cpu basis.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

dev/xen/timer/timer.c:
 - Remove citrical_{enter/exit}, the clock code will already be called
   with preemption disabled when needed. Add a comment to that regard
   in xentimer_get_timecount.
 - Allow xen_fetch_vcpu_time to be called with a specifc vcpu_info
   that will be used to fetch current time.
 - Assert that xentimer_et_start will always be called with preemption
   disabled.
xen: implement an early timer for Xen PVH

When running as a PVH guest, there's no emulated i8254, so we need to
use the Xen PV timer as the early source for DELAY. This change allows
for different implementations of the early DELAY function and
implements a Xen variant for it.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

dev/xen/timer/timer.c:
dev/xen/timer/timer.h:
 - Implement Xen early delay functions using the PV timer and declare
   them.

x86/include/init.h:
 - Add hooks for early clock source initialization and early delay
   functions.

i386/i386/machdep.c:
pc98/pc98/machdep.c:
amd64/amd64/machdep.c:
 - Set early delay hooks to use the i8254 on bare metal.
 - Use clock_init (that will in turn make use of init_ops) to
   initialize the early clock source.

amd64/include/clock.h:
i386/include/clock.h:
 - Declare i8254_delay and clock_init.

i386/xen/clock.c:
 - Rename DELAY to i8254_delay.

x86/isa/clock.c:
 - Introduce clock_init that will take care of initializing the early
   clock by making use of the init_ops hooks.
 - Move non ISA related delay functions to the newly introduced delay
   file.

x86/x86/delay.c:
 - Add moved delay related functions.
 - Implement generic DELAY function that will use the init_ops hooks.

x86/xen/pv.c:
 - Set PVH hooks for the early delay related functions in init_ops.

conf/files.amd64:
conf/files.i386:
conf/files.pc98:
 - Add delay.c to the kernel build.
xen: implement hook to fetch and parse e820 memory map

e820 memory map is fetched using a hypercall under Xen PVH, so add a
hook to init_ops in oder to diverge from bare metal and implement a
Xen variant.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

x86/include/init.h:
 - Add a parse_memmap hook to init_ops, that will be called to fetch
   and parse the memory map.

amd64/amd64/machdep.c:
 - Decouple the fetch and the parse of the memmap, so the parse
   function can be shared with Xen code.
 - Move code around in order to implement the parse_memmap hook.

amd64/include/pc/bios.h:
 - Declare bios_add_smap_entries (implemented in machdep.c).

x86/xen/pv.c:
 - Implement fetching of e820 memmap when running as a PVH guest by
   using the XENMEM_memory_map hypercall.
xen: use the same hypercall mechanism for XEN and XENHVM

Currently XEN (PV) and XENHVM (PVHVM) ports use different ways to
issue hypercalls, unify this by filling the hypercall_page under HVM
also.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

amd64/include/xen/hypercall.h:
 - Unify Xen hypercall code by always using the PV way.

i386/i386/locore.s:
 - Define hypercall_page on i386 XENHVM.

x86/xen/hvm.c:
 - Fill hypercall_page on XENHVM kernels using the HVM method (only
   when running as an HVM guest).
xen: add an apic_enumerator for PVH

On PVH there's no ACPI, so the CPU enumeration must be implemented
using Xen hypercalls.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

x86/xen/pvcpu_enum.c:
 - Enumerate avaiable vCPUs on PVH by using the VCPUOP_is_up
   hypercall.
 - Set vcpu_id for PVH guests.

conf/files.amd64:
 - Include the PV CPU enumerator in the XENHVM build.
xen: add hook for AP bootstrap memory reservation

This hook will only be implemented for bare metal, Xen doesn't require
any bootstrap code since APs are started in long mode with paging
enabled.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

amd64/amd64/machdep.c:
 - Set mp_bootaddress hook for bare metal.

x86/include/init.h:
 - Define mp_bootaddress in init_ops.
xen: changes to hvm code in order to support PVH guests

On PVH we don't need to init the shared info page, or disable emulated
devices. Also, make sure PV IPIs are set before starting the APs.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

x86/xen/hvm.c:
 - Return early from functions that are no-ops on Xen PVH guests.
 - In order to make sure PV IPIs are setup before AP startup,
   initialize them in SI_SUB_SMP-1.
xen: add a hook to perform AP startup

AP startup on PVH follows the PV method, so we need to add a hook in
order to diverge from bare metal.

Approved by: gibbs
Sponsored by: Citrix Systems R&D

amd64/amd64/machdep.c:
 - Add hook for start_all_aps on native (using native_start_all_aps
   defined in mp_machdep).

amd64/amd64/mp_machdep.c:
 - Make some variables global because they will also be used by the
   Xen PVH AP startup code.
 - Use the start_all_aps hook to start APs.
 - Rename start_all_aps to native_start_all_aps.

amd64/include/smp.h:
 - Add declaration for native_start_all_aps.

x86/include/init.h:
 - Declare start_all_aps hook in init_ops.

x86/xen/pv.c:
 - Pick external declarations from mp_machdep.
 - Introduce Xen PV code to start APs on PVH.
 - Set start_all_aps init hook to use the Xen PVH implementation.
Support Last-Modified behind proxies which return UTC instead of GMT.

The standard states that GMT must be used, but that UTC is equivalent. Still
parse UTC as otherwise this causes problems for pkg(8). It will refetch
the repository every time 'pkg update' or other remote operations
are used behind these proxies.

RFC2616: "All HTTP date/time stamps MUST be represented in Greenwich Mean
Time (GMT), without exception. For the purposes of HTTP, GMT is exactly equal
to UTC (Coordinated Universal Time).""

Approved by:	bapt (mentor)
Reviewed by:	des, peter
Sponsored by:	EMC / Isilon Storage Division
MFC after:	1 week
Remove some unnecessary indirection and jump right to the handler functions.
No functional changes.  Rewrite comments, use tabs consistantly, reorder
some of the functions so that similar things are grouped together.
Use panic rather than printf to "handle" an arm26 address exception
(should never happen on arm32).  Pass the right arguments to panic for
the reset exception (which also should never happen).
Replace the userspace atpic stub with a more functional vmm.ko model.

New ioctls VM_ISA_ASSERT_IRQ, VM_ISA_DEASSERT_IRQ and VM_ISA_PULSE_IRQ
can be used to manipulate the pic, and optionally the ioapic, pin state.

Reviewed by:	jhb, neel
Approved by:	neel (co-mentor)