gvisor/pkg/sentry/syscalls/linux/vfs2/sync.go

88 lines
2.5 KiB
Go

// Copyright 2020 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 vfs2
import (
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/sentry/arch"
"gvisor.dev/gvisor/pkg/sentry/kernel"
"gvisor.dev/gvisor/pkg/syserror"
)
// Sync implements Linux syscall sync(2).
func Sync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
return 0, nil, t.Kernel().VFS().SyncAllFilesystems(t)
}
// Syncfs implements Linux syscall syncfs(2).
func Syncfs(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
fd := args[0].Int()
file := t.GetFileVFS2(fd)
if file == nil {
return 0, nil, syserror.EBADF
}
defer file.DecRef()
return 0, nil, file.SyncFS(t)
}
// Fsync implements Linux syscall fsync(2).
func Fsync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
fd := args[0].Int()
file := t.GetFileVFS2(fd)
if file == nil {
return 0, nil, syserror.EBADF
}
defer file.DecRef()
return 0, nil, file.Sync(t)
}
// Fdatasync implements Linux syscall fdatasync(2).
func Fdatasync(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
// TODO(gvisor.dev/issue/1897): Avoid writeback of unnecessary metadata.
return Fsync(t, args)
}
// SyncFileRange implements Linux syscall sync_file_range(2).
func SyncFileRange(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
fd := args[0].Int()
offset := args[1].Int64()
nbytes := args[2].Int64()
flags := args[3].Uint()
if offset < 0 {
return 0, nil, syserror.EINVAL
}
if nbytes < 0 {
return 0, nil, syserror.EINVAL
}
if flags&^(linux.SYNC_FILE_RANGE_WAIT_BEFORE|linux.SYNC_FILE_RANGE_WRITE|linux.SYNC_FILE_RANGE_WAIT_AFTER) != 0 {
return 0, nil, syserror.EINVAL
}
file := t.GetFileVFS2(fd)
if file == nil {
return 0, nil, syserror.EBADF
}
defer file.DecRef()
// TODO(gvisor.dev/issue/1897): Avoid writeback of data ranges outside of
// [offset, offset+nbytes).
return 0, nil, file.Sync(t)
}