Question about clone_range() metadata stability

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi all

A quick question about clone_range() and guarantees around metadata
stability.

Are users required to call fsync/fsync_range() after calling
clone_range() in order to guarantee that the cloned range metadata is
persisted? I'm assuming that it is required in order to guarantee that
data is persisted.

I'm asking because knfsd currently just does a call to
vfs_clone_file_range() when parsing a NFSv4.2 CLONE operation. It does
not call fsync()/fsync_range() on the destination file, and since the
NFSv4.2 protocol does not require you to perform any other operation in
order to persist data/metadata, I'm worried that we may be corrupting
the cloned file if the NFS server crashes at the wrong moment after the
client has been told the clone completed.

Cheers
  Trond
-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@xxxxxxxxxxxxxxx






[Index of Archives]     [Linux Filesystem Development]     [Linux USB Development]     [Linux Media Development]     [Video for Linux]     [Linux NILFS]     [Linux Audio Users]     [Yosemite Info]     [Linux SCSI]

  Powered by Linux