Disintegrate kernel.TaskResources.

This allows us to call kernel.FDMap.DecRef without holding mutexes
cleanly.

PiperOrigin-RevId: 211139657
Change-Id: Ie59d5210fb9282e1950e2e40323df7264a01bcec

1 files changed, 0 insertions, 132 deletions

diff --git a/pkg/sentry/kernel/task_resources.go b/pkg/sentry/kernel/task_resources.go
deleted file mode 100644
index 0832bf989..000000000
--- a/pkg/sentry/kernel/task_resources.go
+++ /dev/null
@@ -1,132 +0,0 @@
-// 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 kernel
-
-import (
-	"gvisor.googlesource.com/gvisor/pkg/abi/linux"
-	"gvisor.googlesource.com/gvisor/pkg/sentry/fs"
-)
-
-// TaskResources is the subset of a task's data provided by its creator that is
-// not provided by the loader.
-//
-// +stateify savable
-type TaskResources struct {
-	// SignalMask is the set of signals whose delivery is currently blocked.
-	//
-	// FIXME: Determine if we also need RealSignalMask
-	SignalMask linux.SignalSet
-
-	// FSContext is the filesystem context.
-	*FSContext
-
-	// FDMap provides access to files to the task.
-	*FDMap
-
-	// Tracks abstract sockets that are in use.
-	AbstractSockets *AbstractSocketNamespace
-}
-
-// newTaskResources returns a new TaskResources, taking an additional reference
-// on fdm.
-func newTaskResources(fdm *FDMap, fc *FSContext) *TaskResources {
-	fdm.IncRef()
-	return &TaskResources{
-		FDMap:           fdm,
-		FSContext:       fc,
-		AbstractSockets: NewAbstractSocketNamespace(),
-	}
-}
-
-// release releases all resources held by the TaskResources. release is called
-// by the task when it exits.
-func (tr *TaskResources) release() {
-	tr.FDMap.DecRef()
-	tr.FDMap = nil
-	tr.FSContext.DecRef()
-	tr.FSContext = nil
-	tr.AbstractSockets = nil
-}
-
-// Fork returns a duplicate of tr.
-//
-// FIXME: Preconditions: When tr is owned by a Task, that task's
-// signal mutex must be locked, or Fork must be called by the task's goroutine.
-func (tr *TaskResources) Fork(shareFiles bool, shareFSContext bool) *TaskResources {
-	var fdmap *FDMap
-	if shareFiles {
-		fdmap = tr.FDMap
-		fdmap.IncRef()
-	} else {
-		fdmap = tr.FDMap.Fork()
-	}
-
-	var fsc *FSContext
-	if shareFSContext {
-		fsc = tr.FSContext
-		fsc.IncRef()
-	} else {
-		fsc = tr.FSContext.Fork()
-	}
-
-	return &TaskResources{
-		SignalMask:      tr.SignalMask,
-		FDMap:           fdmap,
-		FSContext:       fsc,
-		AbstractSockets: tr.AbstractSockets,
-	}
-}
-
-// FDMap returns t's FDMap.
-//
-// Preconditions: The caller must be running on the task goroutine, or t.mu
-// must be locked.
-func (t *Task) FDMap() *FDMap {
-	return t.tr.FDMap
-}
-
-// FSContext returns t's FSContext.
-//
-// Preconditions: The caller must be running on the task goroutine, or t.mu
-// must be locked.
-func (t *Task) FSContext() *FSContext {
-	return t.tr.FSContext
-}
-
-// MountNamespace returns t's MountNamespace. MountNamespace does not take an additional
-// reference on the returned MountNamespace.
-func (t *Task) MountNamespace() *fs.MountNamespace {
-	return t.k.mounts
-}
-
-// AbstractSockets returns t's AbstractSocketNamespace.
-func (t *Task) AbstractSockets() *AbstractSocketNamespace {
-	return t.tr.AbstractSockets
-}
-
-// IsChrooted returns true if the root directory of t's FSContext is not the
-// root directory of t's MountNamespace.
-//
-// Preconditions: The caller must be running on the task goroutine, or t.mu
-// must be locked.
-func (t *Task) IsChrooted() bool {
-	realRoot := t.k.mounts.Root()
-	defer realRoot.DecRef()
-	root := t.tr.FSContext.RootDirectory()
-	if root != nil {
-		defer root.DecRef()
-	}
-	return root != realRoot
-}