48 lines
1.6 KiB
Go
48 lines
1.6 KiB
Go
// Copyright 2018 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 usermem
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import (
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"sync/atomic"
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"unsafe"
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"gvisor.dev/gvisor/pkg/atomicbitops"
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"gvisor.dev/gvisor/pkg/context"
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)
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// SwapUint32 implements IO.SwapUint32.
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func (b *BytesIO) SwapUint32(ctx context.Context, addr Addr, new uint32, opts IOOpts) (uint32, error) {
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if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil {
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return 0, rngErr
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}
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return atomic.SwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), new), nil
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}
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// CompareAndSwapUint32 implements IO.CompareAndSwapUint32.
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func (b *BytesIO) CompareAndSwapUint32(ctx context.Context, addr Addr, old, new uint32, opts IOOpts) (uint32, error) {
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if _, rngErr := b.rangeCheck(addr, 4); rngErr != nil {
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return 0, rngErr
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}
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return atomicbitops.CompareAndSwapUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)])), old, new), nil
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}
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// LoadUint32 implements IO.LoadUint32.
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func (b *BytesIO) LoadUint32(ctx context.Context, addr Addr, opts IOOpts) (uint32, error) {
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if _, err := b.rangeCheck(addr, 4); err != nil {
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return 0, err
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}
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return atomic.LoadUint32((*uint32)(unsafe.Pointer(&b.Bytes[int(addr)]))), nil
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}
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