frostfs-s3-gw/legacy/fallocate_linux.go
2020-07-09 12:28:51 +03:00

35 lines
1.2 KiB
Go

// +build linux
/*
* MinIO Cloud Storage, (C) 2016 MinIO, Inc.
*
* 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 legacy
import "syscall"
// Fallocate uses the linux Fallocate syscall, which helps us to be
// sure that subsequent writes on a file just created will not fail,
// in addition, file allocation will be contigous on the disk
func Fallocate(fd int, offset int64, len int64) error {
// No need to attempt fallocate for 0 length.
if len == 0 {
return nil
}
// Don't extend size of file even if offset + len is
// greater than file size from <bits/fcntl-linux.h>.
fallocFLKeepSize := uint32(1)
return syscall.Fallocate(fd, fallocFLKeepSize, offset, len)
}