khenaidoo | 59ce9dd | 2019-11-11 13:05:32 -0500 | [diff] [blame^] | 1 | // Copyright 2016 The etcd Authors |
| 2 | // |
| 3 | // Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | // you may not use this file except in compliance with the License. |
| 5 | // You may obtain a copy of the License at |
| 6 | // |
| 7 | // http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | // |
| 9 | // Unless required by applicable law or agreed to in writing, software |
| 10 | // distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | // See the License for the specific language governing permissions and |
| 13 | // limitations under the License. |
| 14 | |
| 15 | // +build linux |
| 16 | |
| 17 | package fileutil |
| 18 | |
| 19 | import ( |
| 20 | "os" |
| 21 | "syscall" |
| 22 | ) |
| 23 | |
| 24 | func preallocExtend(f *os.File, sizeInBytes int64) error { |
| 25 | // use mode = 0 to change size |
| 26 | err := syscall.Fallocate(int(f.Fd()), 0, 0, sizeInBytes) |
| 27 | if err != nil { |
| 28 | errno, ok := err.(syscall.Errno) |
| 29 | // not supported; fallback |
| 30 | // fallocate EINTRs frequently in some environments; fallback |
| 31 | if ok && (errno == syscall.ENOTSUP || errno == syscall.EINTR) { |
| 32 | return preallocExtendTrunc(f, sizeInBytes) |
| 33 | } |
| 34 | } |
| 35 | return err |
| 36 | } |
| 37 | |
| 38 | func preallocFixed(f *os.File, sizeInBytes int64) error { |
| 39 | // use mode = 1 to keep size; see FALLOC_FL_KEEP_SIZE |
| 40 | err := syscall.Fallocate(int(f.Fd()), 1, 0, sizeInBytes) |
| 41 | if err != nil { |
| 42 | errno, ok := err.(syscall.Errno) |
| 43 | // treat not supported as nil error |
| 44 | if ok && errno == syscall.ENOTSUP { |
| 45 | return nil |
| 46 | } |
| 47 | } |
| 48 | return err |
| 49 | } |