fusefrontend: doWrite: no need to take HeaderLock.RLock()

Other writers are blocked by ContentLock already.
This commit is contained in:
Jakob Unterwurzacher 2018-07-15 12:40:23 +02:00
parent bbf5b72fff
commit 55bb22bad6
1 changed files with 4 additions and 8 deletions

View File

@ -266,13 +266,13 @@ func (f *File) Read(buf []byte, off int64) (resultData fuse.ReadResult, code fus
//
// Empty writes do nothing and are allowed.
func (f *File) doWrite(data []byte, off int64) (uint32, fuse.Status) {
// Read header from disk, create a new one if the file is empty
f.fileTableEntry.HeaderLock.RLock()
// If the file ID is not cached, read it from disk
if f.fileTableEntry.ID == nil {
f.fileTableEntry.HeaderLock.RUnlock()
// Somebody else may write the header here, but this would do no harm.
// Block other readers while we mess with the file header. Other writers
// are blocked by ContentLock already.
f.fileTableEntry.HeaderLock.Lock()
tmpID, err := f.readFileID()
// Write a new file header if the file is empty
if err == io.EOF {
tmpID, err = f.createHeader()
}
@ -282,11 +282,7 @@ func (f *File) doWrite(data []byte, off int64) (uint32, fuse.Status) {
}
f.fileTableEntry.ID = tmpID
f.fileTableEntry.HeaderLock.Unlock()
// The file ID may change in here. This does no harm because we
// re-read it after the RLock().
f.fileTableEntry.HeaderLock.RLock()
}
defer f.fileTableEntry.HeaderLock.RUnlock()
// Handle payload data
dataBuf := bytes.NewBuffer(data)
blocks := f.contentEnc.ExplodePlainRange(uint64(off), uint64(len(data)))