Check in gVisor.

PiperOrigin-RevId: 194583126
Change-Id: Ica1d8821a90f74e7e745962d71801c598c652463

1 files changed, 71 insertions, 0 deletions

diff --git a/pkg/sentry/platform/ring0/kernel.go b/pkg/sentry/platform/ring0/kernel.go
new file mode 100644
index 000000000..b0471ab9a
--- /dev/null
+++ b/pkg/sentry/platform/ring0/kernel.go
@@ -0,0 +1,71 @@
+// Copyright 2018 Google Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package ring0
+
+// New creates a new kernel.
+//
+// N.B. that constraints on KernelOpts must be satisfied.
+//
+// Init must have been called.
+func New(opts KernelOpts) *Kernel {
+	k := new(Kernel)
+	k.init(opts)
+	return k
+}
+
+// NewCPU creates a new CPU associated with this Kernel.
+//
+// Note that execution of the new CPU must begin at Start, with constraints as
+// documented. Initialization is not completed by this method alone.
+//
+// See also Init.
+func (k *Kernel) NewCPU() *CPU {
+	c := new(CPU)
+	c.Init(k)
+	return c
+}
+
+// Halt halts execution.
+func Halt()
+
+// Current returns the current CPU.
+//
+// Its use is only legal in the KernelSyscall and KernelException contexts,
+// which must all be guarded go:nosplit.
+func Current() *CPU
+
+// defaultSyscall is the default syscall hook.
+//
+//go:nosplit
+func defaultSyscall() { Halt() }
+
+// defaultException is the default exception hook.
+//
+//go:nosplit
+func defaultException(Vector) { Halt() }
+
+// Init allows the initialization of a CPU from a kernel without allocation.
+// The same constraints as NewCPU apply.
+//
+// Init allows embedding in other objects.
+func (c *CPU) Init(k *Kernel) {
+	c.self = c   // Set self reference.
+	c.kernel = k // Set kernel reference.
+	c.init()     // Perform architectural init.
+
+	// Defaults.
+	c.KernelSyscall = defaultSyscall
+	c.KernelException = defaultException
+}