- 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

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

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

Remove obsolete comment about lack of locking for MMIO range lookup.

Pointed out by: Tycho Nightingale (tycho.nightingale@plurisbusnetworks.com)

Change name of variable from 'rwlock' to more descriptive 'mmio_rwlock'

Requested by: grehan
Obtained from: NetApp

Improve PCI BAR emulation:
- Respect the MEMEN and PORTEN bits in the command register
- Allow the guest to reprogram the address decoded by the BAR

Submitted by: Gopakumar T
Obtained from: NetApp

Add the ability to have a 'fallback' search for memory ranges.
These set of ranges will be looked at if a standard memory
range isn't found, and won't be installed in the cache.
Use this to implement the memory behaviour of the PCI hole on
x86 systems, where writes are ignored and reads always return -1.
This allows breakpoints to be set when issuing a 'boot -d', which
has the side effect of accessing the PCI hole when changing the
PTE protection on kernel code, since the pmap layer hasn't been
initialized (a bug, but present in existing FreeBSD releases so
has to be handled).

Reviewed by: neel
Obtained from: NetApp

Merge projects/bhyve to head.

'bhyve' was developed by grehan@ and myself at NetApp (thanks!).

Special thanks to Peter Snyder, Joe Caradonna and Michael Dexter for their
support and encouragement.

Obtained from: NetApp

Cleanup the user-space paging exit handler now that the unified instruction
emulation is in place.

Obtained from: NetApp

Revamp the x86 instruction emulation in bhyve.

On a nested page table fault the hypervisor will:
- fetch the instruction using the guest %rip and %cr3
- decode the instruction in 'struct vie'
- emulate the instruction in host kernel context for local apic accesses
- any other type of mmio access is punted up to user-space (e.g. ioapic)

The decoded instruction is passed as collateral to the user-space process
that is handling the PAGING exit.

The emulation code is fleshed out to include more addressing modes (e.g. SIB)
and more types of operands (e.g. imm8). The source code is unified into a
single file (vmm_instruction_emul.c) that is compiled into vmm.ko as well
as /usr/sbin/bhyve.

Reviewed by: grehan
Obtained from: NetApp

Rework how guest MMIO regions are dealt with.

- New memory region interface. An RB tree holds the regions,
with a last-found per-vCPU cache to deal with the common case
of repeated guest accesses to MMIO registers in the same page.

- Support memory-mapped BARs in PCI emulation.

mem.c/h - memory region interface

instruction_emul.c/h - remove old region interface.
Use gpa from EPT exit to avoid a tablewalk to
determine operand address. Determine operand size
and use when calling through to region handler.

fbsdrun.c - call into region interface on paging
exit. Distinguish between instruction emul error
and region not found

pci_emul.c/h - implement new BAR callback api.
Split BAR alloc routine into routines that
require/don't require the BAR phys address.

ioapic.c
pci_passthru.c
pci_virtio_block.c
pci_virtio_net.c
pci_uart.c - update to new BAR callback i/f

Reviewed by: neel
Obtained from: NetApp