bhyve: Use vm_get_highmem_base() instead of hard-coding the value

This reduces the coupling between libvmmapi (which creates the highmem
segment) and bhyve, in preparation for the arm64 port.

No functional change intended.

Reviewed by: corvink, jhb
MFC after: 2 weeks
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40992

bhyve: increase SNAPSHOT_BUFFER_SIZE

After commit fb51ddb20d57, suspending a vm fails with the error:
vm_snapshot_buf: buffer too small

Sponsored by: vStack
Reviewed by: markj, rew
Fixes: fb51ddb20d57 ("bhyve: increase fbuf display resolution limit")
Differential Revision: https://reviews.freebsd.org/D43218

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

bhyve: Remove init_snapshot() and initialize static vars

vCPU threads are starting before init_snapshot() is called. That can lead
to corruption of vcpu_lock userspace mutex (snapshot.c) and then VM hangs
in acquiring that mutex.

init_snapshot() initializes only static variables (mutex, cv) and that
code can be optimized and removed.

Fixes: 9a9a248964696 ("bhyve: init checkput before caph_enter")
Reviewed by: markj
MFC after: 1 week
Sponsored by: vStack

bhyve: Replace many fprintf(stderr, ...) calls with EPRINTLN

EPRINTLN handles newlines appropriately when stdout/stderr have been
reused as the backend for a serial port.

For bhyverun.c itself, the rule this attempts to follow is to use
regular fprintf/perror/warn/err prior to init_pci() (which is when
serial ports are configured) and to switch to EPRINTLN afterwards.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D42182

bhyve: Remove some unneeded includes from snapshot.c

MFC after: 1 week
Sponsored by: Innovate UK

bhyve: Move more amd64-specific code under amd64/

mptable and the e820 are both rather amd64-specific and can be moved
easily.

In the case of e820, move the registration with qemu_fwcfg into e820.c,
as it simplifies bhyverun.c a bit and I can't see any downsides.

No functional change intended.

Reviewed by: corvink, jhb, emaste
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40552

bhyve: Move some more amd64-specific drivers to their own subdir

No functional change intended.

Reviewed by: corvink, jhb, emaste
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40551

bhyve: Start moving machine-dependent code into subdirectories

In preparation for an arm64 port, make an easy change which puts some
machine-dependent code in its own directory.

Going forward, code which is only used on one platform should live in a
MD directory. We should strive to layer modules in such a way as to
avoid polluting shared code with lots of ifdefs. For some existing
files this will take some effort.

task_switch.c and fwctl.c are an easy place to start: the former is very
x86-specific, and the latter provides an I/O port interface which can't
be used on anything other than x86. (fwcfg as implemented has the same
problem, but QEMU also supports a MMIO fwcfg interface.) So I propose
that we start by simply making those files conditional.

Reviewed by: corvink, jhb
MFC after: 1 week
Sponsored by: Innovate UK
Differential Revision: https://reviews.freebsd.org/D40501

Remove $FreeBSD$: one-line .c pattern

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

Revert "bhyve: add command line parameter and parsing for migration"

Unfortunately, this feature didn't receive much feedback in the past.
However, after committing this, some people came up and complain that
this feature requires some more discussion before upstreaming it.
Additionally, it wasn't a good idea to start this new feature by adding
a new command line parameter as it fixes the user interface.

This reverts commit c9fdd4f3cc18c03683de85318ba8d318f96b58c4.

bhyve: Remove some unneeded includes of segments.h

They are not needed and are specific to x86. No functional change
intended.

MFC after: 1 week
Sponsored by: Innovate UK

bhyve: add command line parameter and parsing for migration

This covers warm and live migration.

Reviewed by: corvink
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D34717

bhyve: use pci_next() to save/restore pci devices

Current snapshot implementation doesn't support multiple devices with
similar type. For example, two virtio-blk or two CD-ROM-s, etc.

So the following configuration cannot be restored.

bhyve \
-s 3,virtio-blk,disk.img \
-s 4,virtio-blk,disk2.img

In some cases it is restored silently, but doesn't work. In some cases
it fails during restore stage.

This commit fixes that issue.

Reviewed by: corvink, rew
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D40109

bhyve: rename 'user_dev' with 'devices'

Bhyve don't use 'user' specifier for emulated devices. And
using 'user' adds duality.

Reviewed by: corvink, rew
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D40106

bhyve: simplify restore of kernel structs

Both devices and kernel struct can use the same 'lookup_dev'
function instead of having duplicated code.

Reviewed by: corvink, rew
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D40105

bhyve: rename 'structs' snapshot key with 'kern_structs'

Using key 'structs' is ambiguous. This section contains data
related to the kernel. It should use a more informative naming.

Reviewed by: corvink, rew
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D40104

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

bhyve: use directory file descriptor for checkpoint

This is required to enable capsicum for the snapshot code.

Reviewed by: corvink
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D38858

bhyve: Remove vmctx member from struct vm_snapshot_meta.

This is a userland-only pointer that isn't relevant to the kernel and
doesn't belong in the ioctl structure shared between userland and the
kernel. For the kernel, the old structure for the ioctl is still
supported under COMPAT_FREEBSD13.

This changes vm_snapshot_req() in libvmmapi to accept an explicit
vmctx argument.

It also changes vm_snapshot_guest2host_addr to take an explicit vmctx
argument. As part of this change, move the declaration for this
function and its wrapper macro from vmm_snapshot.h to snapshot.h as it
is a userland-only API.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D38125

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: add cap limits for ipc socket

Reviewed by: corvink, markj
MFC after: 1 week
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D38856

bhyve: fix restore of kernel structs

vmx_snapshot() and svm_snapshot() do not save any data and error occurs at
resume:

Restoring kernel structs...
vm_restore_kern_struct: Kernel struct size was 0 for: vmx
Failed to restore kernel structs.

Reviewed by: corvink, markj
Fixes: 39ec056e6dbd89e26ee21d2928dbd37335de0ebc ("vmm: Rework snapshotting of CPU-specific per-vCPU data.")
MFC after: 2 weeks
Sponsored by: vStack
Differential Revision: https://reviews.freebsd.org/D38476

bhyve: Remove vmctx argument from PCI device model methods.

Most of these arguments were unused. Device models which do need
access to the vmctx in one of these methods can obtain it from the
pi_vmctx member of the pci_devinst argument instead.

Reviewed by: corvink, markj
Differential Revision: https://reviews.freebsd.org/D38096

bhyve: Drop volatile qualifiers from snapshot code

They accomplish nothing since the qualifier is casted away in calls to
memcpy() and copyin()/copyout(). No functional change intended.

MFC after: 2 weeks
Reviewed by: corvink, jhb
Differential Revision: https://reviews.freebsd.org/D37292

bhyve: Address some signed/unsigned comparison warnings

MFC after: 1 week

bhyve: Fix some warnings in the snapshot code

- Qualify unexported symbols with "static".
- Drop some unnecessary and incorrect casts.
- Avoid arithmetic on void pointers.
- Avoid signed/unsigned comparisons in loops which use nitems() as a
bound.

No functional change intended.

MFC after: 1 week

bhyve: Avoid arithmetic on void pointers

No functional change intended.

MFC after: 1 week

bhyve: Annotate unused function parameters

MFC after: 1 week

bhyve/snapshot: ..back to SOCK_STREAM

Now that nvlist_send()/nvlist_recv() are being used, ditch the datagram
socket.

Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D34863

bhyve: use linker set for ipc commands

Reviewed by: markj, jhb
Differential Revision: https://reviews.freebsd.org/D34760

bhyve: sweep MAX_VMNAME

MAX_VMNAME is no longer used.

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D34292

bhyve/snapshot: limit snapshot filename to NAME_MAX

NAME_MAX is a better fit since strcat_extension() constructs the
filename of the snapshot file.

Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D34291

libvmm: constify vm_get_name()

Allows callers of vm_get_name() to retrieve the vm name without having
to allocate a buffer.

While in the vicinity, do minor cleanup in vm_snapshot_basic_metadata().

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D34290

bhyve/snapshot: use a string for cmd element in the nvlist

The nvlist for a checkpoint request will now look like:

{ cmd="checkpoint", suspend="true/false", filename="afilename" }

Reviewed by: jhb
Suggested by: jhb
Differential Revision: https://reviews.freebsd.org/D34237

bhyve/snapshot: switch to nvlist for snapshot requests

Switch to using an nvlist with nvlist_send()/nvlist_recv() to
communicate from bhyvectl(8) to bhyve(8).

The idea is that a bhyve process receives a command with with a set of
arguments. The nvlist here is structured to reflect that premise.

For example, to snapshot the vm, the expected nvlist looks like:

{ cmd=START_CHECKPOINT, filename="filename" }

Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D33977

bhyve/snapshot: fix pthread_create() error check

pthread_create() returns 0 on success or an error number on failure.

Reviewed by: khng, markj
Differential Revision: https://reviews.freebsd.org/D33930

bhyve/snapshot: split up mutex/cond initialization from socket creation

Move initialization of the mutex/condition variables required by the
save/restore feature to their own function.

The unix domain socket that facilitates communication between bhyvectl
and bhyve doesn't rely on these variables in order to be functional.

Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D30281

bhyve/snapshot: provide a way to send other messages/data to bhyve

This is a step towards sending messages (other than suspend/checkpoint)
from bhyvectl to bhyve.

Introduce a new struct, ipc_message - this struct stores the type of
message and a union containing message specific structures for the type
of message being sent.

Reviewed by: grehan
Differential Revision: https://reviews.freebsd.org/D30221

bhyve/snapshot: use SOCK_DGRAM instead of SOCK_STREAM

The save/restore feature uses a unix domain socket to send messages
from bhyvectl(8) to a bhyve(8) process. A datagram socket will suffice
for this.

An added benefit of using a datagram socket is simplified code. For
bhyve, the listen/accept calls are dropped; and for bhyvectl, the
connect() call is dropped.

EPRINTLN handles raw mode for bhyve(8), use it to print error messages.

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D28983

bhyve/snapshot: drop mkdir when creating the unix domain socket

Add /var/run/bhyve/ to BSD.var.dist so we don't have to call mkdir when
creating the unix domain socket for a given bhyve vm.

The path to the unix domain socket for a bhyve vm will now be
/var/run/bhyve/vmname instead of /var/run/bhyve/checkpoint/vmname

Move BHYVE_RUN_DIR from snapshot.c to snapshot.h so it can be shared
to bhyvectl(8).

Reviewed by: jhb
Differential Revision: https://reviews.freebsd.org/D28783

Remove bvmconsole and bvmdebug.

Now that bhyve(8) supports UART, bvmconsole and bvmdebug are no longer needed.

This also removes the '-b' and '-g' flag from bhyve(8). These two flags were
marked deprecated in r368519.

Reviewed by: grehan, kevans
Approved by: kevans (mentor)
Differential Revision: https://reviews.freebsd.org/D27490

Suspend I/O on ahci-cd devices during a snapshot.

Submitted by: Vitaliy Gusev <gusev.vitaliy@gmail.com>

bhyve: Add snapshot support for virtio-rnd.

This uses the same snapshot routine as other VirtIO devices.

Submitted by: Vitaliy Gusev <gusev.vitaliy@gmail.com>
Differential Revision: https://reviews.freebsd.org/D26265

Initial support for bhyve save and restore.

Save and restore (also known as suspend and resume) permits a snapshot
to be taken of a guest's state that can later be resumed. In the
current implementation, bhyve(8) creates a UNIX domain socket that is
used by bhyvectl(8) to send a request to save a snapshot (and
optionally exit after the snapshot has been taken). A snapshot
currently consists of two files: the first holds a copy of guest RAM,
and the second file holds other guest state such as vCPU register
values and device model state.

To resume a guest, bhyve(8) must be started with a matching pair of
command line arguments to instantiate the same set of device models as
well as a pointer to the saved snapshot.

While the current implementation is useful for several uses cases, it
has a few limitations. The file format for saving the guest state is
tied to the ABI of internal bhyve structures and is not
self-describing (in that it does not communicate the set of device
models present in the system). In addition, the state saved for some
device models closely matches the internal data structures which might
prove a challenge for compatibility of snapshot files across a range
of bhyve versions. The file format also does not currently support
versioning of individual chunks of state. As a result, the current
file format is not a fixed binary format and future revisions to save
and restore will break binary compatiblity of snapshot files. The
goal is to move to a more flexible format that adds versioning,
etc. and at that point to commit to providing a reasonable level of
compatibility. As a result, the current implementation is not enabled
by default. It can be enabled via the WITH_BHYVE_SNAPSHOT=yes option
for userland builds, and the kernel option BHYVE_SHAPSHOT.

Submitted by: Mihai Tiganus, Flavius Anton, Darius Mihai
Submitted by: Elena Mihailescu, Mihai Carabas, Sergiu Weisz
Relnotes: yes
Sponsored by: University Politehnica of Bucharest
Sponsored by: Matthew Grooms (student scholarships)
Sponsored by: iXsystems
Differential Revision: https://reviews.freebsd.org/D19495