tree f1c850d39be6b1670e50eaf8baf92d4cc95831e6
parent 651b0e702981304f77091b82870a01480705f4fe
author Trond Myklebust <trond.myklebust@primarydata.com> 1466891140 -0400
committer Trond Myklebust <trond.myklebust@primarydata.com> 1467760266 -0400

NFS: Getattr doesn't require data sync semantics

When retrieving stat() information, NFS unfortunately does require us to
sync writes to disk in order to ensure that mtime and ctime are up to
date. However we shouldn't have to ensure that those writes are persisted.

Relaxing that requirement does mean that we may see an mtime/ctime change
if the server reboots and forces us to replay all writes.

The exception to this rule are pNFS clients that are required to send
layoutcommit, however that is dealt with by the call to pnfs_sync_inode()
in _nfs_revalidate_inode().

Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>