Files
gotgt/pkg/scsi/backingstore/common.go
chessman 22d47a9212 enable UNMAP when LUN is thin provisioned
- support Block Limits VPD page (0xB0)
 - add UNMAP to REPORT SUPPORTED OPERATION CODES
 - READ CAPACITY(16): set LBPME when Thin provisioning is enabled
 - move Thinprovisioning and BlockShift to config
 - add Unmap to BackingStore
2019-05-28 13:53:06 +03:00

120 lines
2.6 KiB
Go

/*
Copyright 2017 The GoStor Authors All rights reserved.
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 backingstore
import (
"fmt"
"os"
log "github.com/Sirupsen/logrus"
"github.com/gostor/gotgt/pkg/api"
"github.com/gostor/gotgt/pkg/scsi"
"github.com/gostor/gotgt/pkg/util"
)
const (
FileBackingStorage = "file"
)
func init() {
scsi.RegisterBackingStore(FileBackingStorage, new)
}
type FileBackingStore struct {
scsi.BaseBackingStore
file *os.File
}
func new() (api.BackingStore, error) {
return &FileBackingStore{
BaseBackingStore: scsi.BaseBackingStore{
Name: FileBackingStorage,
DataSize: 0,
OflagsSupported: 0,
},
}, nil
}
func (bs *FileBackingStore) Open(dev *api.SCSILu, path string) error {
if finfo, err := os.Stat(path); err != nil {
return err
} else {
bs.DataSize = uint64(finfo.Size())
}
f, err := os.OpenFile(path, os.O_RDWR, os.ModePerm)
bs.file = f
return err
}
func (bs *FileBackingStore) Close(dev *api.SCSILu) error {
return bs.file.Close()
}
func (bs *FileBackingStore) Init(dev *api.SCSILu, Opts string) error {
return nil
}
func (bs *FileBackingStore) Exit(dev *api.SCSILu) error {
return nil
}
func (bs *FileBackingStore) Size(dev *api.SCSILu) uint64 {
return bs.DataSize
}
func (bs *FileBackingStore) Read(offset, tl int64) ([]byte, error) {
if bs.file == nil {
return nil, fmt.Errorf("Backend store is nil")
}
tmpbuf := make([]byte, tl)
length, err := bs.file.ReadAt(tmpbuf, offset)
if err != nil {
return nil, err
}
if length != len(tmpbuf) {
return nil, fmt.Errorf("read is not same length of length")
}
return tmpbuf, nil
}
func (bs *FileBackingStore) Write(wbuf []byte, offset int64) error {
length, err := bs.file.WriteAt(wbuf, offset)
if err != nil {
log.Error(err)
return err
}
if length != len(wbuf) {
return fmt.Errorf("write is not same length of length")
}
return nil
}
func (bs *FileBackingStore) DataSync() error {
return util.Fdatasync(bs.file)
}
func (bs *FileBackingStore) DataAdvise(offset, length int64, advise uint32) error {
return util.Fadvise(bs.file, offset, length, advise)
}
func (bs *FileBackingStore) Unmap() error {
return nil
}