62 lines
1.8 KiB
Go
62 lines
1.8 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 vfs2
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import (
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"gvisor.dev/gvisor/pkg/abi/linux"
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"gvisor.dev/gvisor/pkg/sentry/arch"
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"gvisor.dev/gvisor/pkg/sentry/fsimpl/eventfd"
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"gvisor.dev/gvisor/pkg/sentry/kernel"
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"gvisor.dev/gvisor/pkg/syserror"
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)
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// Eventfd2 implements linux syscall eventfd2(2).
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func Eventfd2(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
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initVal := uint64(args[0].Uint())
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flags := uint(args[1].Uint())
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allOps := uint(linux.EFD_SEMAPHORE | linux.EFD_NONBLOCK | linux.EFD_CLOEXEC)
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if flags & ^allOps != 0 {
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return 0, nil, syserror.EINVAL
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}
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vfsObj := t.Kernel().VFS()
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fileFlags := uint32(linux.O_RDWR)
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if flags&linux.EFD_NONBLOCK != 0 {
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fileFlags |= linux.O_NONBLOCK
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}
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semMode := flags&linux.EFD_SEMAPHORE != 0
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eventfd, err := eventfd.New(vfsObj, initVal, semMode, fileFlags)
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if err != nil {
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return 0, nil, err
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}
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defer eventfd.DecRef()
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fd, err := t.NewFDFromVFS2(0, eventfd, kernel.FDFlags{
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CloseOnExec: flags&linux.EFD_CLOEXEC != 0,
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})
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if err != nil {
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return 0, nil, err
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}
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return uintptr(fd), nil, nil
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}
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// Eventfd implements linux syscall eventfd(2).
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func Eventfd(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
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args[1].Value = 0
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return Eventfd2(t, args)
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}
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