32 lines
1.0 KiB
Go
32 lines
1.0 KiB
Go
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// Copyright 2019 The gVisor Authors.
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//
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package gofer
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import (
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"gvisor.dev/gvisor/pkg/usermem"
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)
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// This are equivalent to usermem.Addr.RoundDown/Up, but without the
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// potentially truncating conversion to usermem.Addr. This is necessary because
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// there is no way to define generic "PageRoundDown/Up" functions in Go.
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func pageRoundDown(x uint64) uint64 {
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return x &^ (usermem.PageSize - 1)
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}
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func pageRoundUp(x uint64) uint64 {
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return pageRoundDown(x + usermem.PageSize - 1)
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}
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