usr.sbin: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

libvmmapi: Add a struct vcpu and use it in most APIs.

This replaces the 'struct vm, int vcpuid' tuple passed to most API
calls and is similar to the changes recently made in vmm(4) in the
kernel.

struct vcpu is an opaque type managed by libvmmapi. For now it stores
a pointer to the VM context and an integer id.

As an immediate effect this removes the divergence between the kernel
and userland for the instruction emulation code introduced by the
recent vmm(4) changes.

Since this is a major change to the vmmapi API, bump VMMAPI_VERSION to
0x200 (2.0) and the shared library major version.

While here (and since the major version is bumped), remove unused
vcpu argument from vm_setup_pptdev_msi*().

Add new functions vm_suspend_all_cpus() and vm_resume_all_cpus() for
use by the debug server. The underyling ioctl (which uses a vcpuid of
-1) remains unchanged, but the userlevel API now uses separate
functions for global CPU suspend/resume.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D38124

bhyve: Mark variables and functions as static where appropriate

Mark them const as well when it makes sense to do so. No functional
change intended.

MFC after: 1 week
Sponsored by: The FreeBSD Foundation

bhyve: Allocate mmio_hint array based on number of guest CPUs.

This avoids an instance of hardcoding VM_MAXCPU in userspace.

Reviewed by: grehan
Differential Revision: https://reviews.freebsd.org/D34489

bhyve: clean up trailing whitespaces

Clean up trailing whitespaces. No functional changes.

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D33681

bhyve: enhance debug info for memory range clash

Explain what the two clashing regions are.

Reivewed by: grehan, jhb
Differential Revision: https://reviews.freebsd.org/D29696
Pull Request: https://github.com/freebsd/freebsd-src/pull/463

Add support for writing to guest memory in the debug server.

- Add a write_mem counterpart to read_mem to handle writes to MMIO.
- Add support for the GDB 'M' packet to write bytes to the guest's
memory. For MMIO writes, attempt to batch writes up into words.
This is imprecise, but if you write a single 2 or 4-byte aligned
word, it should be treated as a single MMIO write operation.
- While here, tidy up the parsing of the 'm' command used for reading
memory to match 'M'.

Reviewed by: markj, Scott Phillips <d.scott.phillips@intel.com>
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D20307

While I was investigating CID 1194192 related with a resource leak on mrp memory
allocation, I could identify that actually we use this pointer on pci_emul.c as
well as on vga.c source file.

I have reworked the logic here to make it more readable and also add a warn to
explicit show the function where the memory allocation error could happen,
also sort headers.

Also CID 1194192 was marked as "Intentional".

Obtained from: TrueOS
MFC after: 4 weeks.
Sponsored by: iXsystems Inc.

pthread_rwlock_unlock(3) returns 0 if successful, otherwise an error number
will be returned to indicate the error, so I'm applying an assert(3) to do
a sanity check of the return value.

Reported by: Coverity CID: 1391235, 1193654 and 1193651
Reviewed by: grehan
MFC after: 4 weeks.
Sponsored by: iXsystems Inc.
Differential Revision: https://reviews.freebsd.org/D15533

Initial debug server for bhyve.

This commit adds a new debug server to bhyve. Unlike the existing -g
option which provides an efficient connection to a debug server
running in the guest OS, this debug server permits inspection and
control of the guest from within the hypervisor itself without
requiring any cooperation from the guest. It is similar to the debug
server provided by qemu.

To avoid conflicting with the existing -g option, a new -G option has
been added that accepts a TCP port. An IPv4 socket is bound to this
port and listens for connections from debuggers. In addition, if the
port begins with the character 'w', the hypervisor will pause the
guest at the first instruction until a debugger attaches and
explicitly continues the guest. Note that only a single debugger can
attach to a guest at a time.

Virtual CPUs are exposed to the remote debugger as threads. General
purpose register values can be read for each virtual CPU. Other
registers cannot currently be read, and no register values can be
changed by the debugger.

The remote debugger can read guest memory but not write to guest
memory. To facilitate source-level debugging of the guest, memory
addresses from the debugger are treated as virtual addresses (rather
than physical addresses) and are resolved to a physical address using
the active virtual address translation of the current virtual CPU.
Memory reads should honor memory mapped I/O regions, though the debug
server does not attempt to honor any alignment or size constraints
when accessing MMIO.

The debug server provides limited support for controlling the guest.
The guest is suspended when a debugger is attached and resumes when a
debugger detaches. A debugger can suspend a guest by sending a Ctrl-C
request (e.g. via Ctrl-C in GDB). A debugger can also continue a
suspended guest while remaining attached. Breakpoints are not yet
supported. Single stepping is supported on Intel CPUs that support
MTRAP VM exits, but is not available on other systems.

While the current debug server has limited functionality, it should
at least be usable for basic debugging now. It is also a useful
checkpoint to serve as a base for adding additional features.

Reviewed by: grehan
Differential Revision: https://reviews.freebsd.org/D15022

various: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Support PCI extended config space in bhyve.

Add the ACPI MCFG table to advertise the extended config memory window.

Introduce a new flag MEM_F_IMMUTABLE for memory ranges that cannot be deleted
or moved in the guest's address space. The PCI extended config space is an
example of an immutable memory range.

Add emulation for the "movzw" instruction. This instruction is used by FreeBSD
to read a 16-bit extended config space register.

CR: https://phabric.freebsd.org/D505
Reviewed by: jhb, grehan
Requested by: tychon

Emulate instructions emitted by OpenBSD/i386 version 5.5:
- CMP REG, r/m
- MOV AX/EAX/RAX, moffset
- MOV moffset, AX/EAX/RAX
- PUSH r/m

Consolidate all the information needed by the guest page table walker into
'struct vm_guest_paging'.

Check for canonical addressing in vmm_gla2gpa() and inject a protection
fault into the guest if a violation is detected.

If the page table walk is restarted in vmm_gla2gpa() then reset 'ptpphys' to
point to the root of the page tables.

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

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