32 lines
1.0 KiB
Go
32 lines
1.0 KiB
Go
// Copyright 2019 The gVisor Authors.
|
|
//
|
|
// 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 gofer
|
|
|
|
import (
|
|
"gvisor.dev/gvisor/pkg/usermem"
|
|
)
|
|
|
|
// This are equivalent to usermem.Addr.RoundDown/Up, but without the
|
|
// potentially truncating conversion to usermem.Addr. This is necessary because
|
|
// there is no way to define generic "PageRoundDown/Up" functions in Go.
|
|
|
|
func pageRoundDown(x uint64) uint64 {
|
|
return x &^ (usermem.PageSize - 1)
|
|
}
|
|
|
|
func pageRoundUp(x uint64) uint64 {
|
|
return pageRoundDown(x + usermem.PageSize - 1)
|
|
}
|