On Sat, 2017-06-24 at 04:59 -0700, Christoph Hellwig wrote: > On Tue, Jun 20, 2017 at 01:44:44PM -0400, Jeff Layton wrote: > > In order to query for errors with errseq_t, you need a previously- > > sampled point from which to check. When you call > > filemap_write_and_wait_range though you don't have a struct file and so > > no previously-sampled value. > > So can we simply introduce variants of them that take a struct file? > That would be: > > a) less churn > b) less code > c) less chance to get data integrity wrong Yeah, I had that thought after I sent the reply to you earlier. The main reason I didn't do that before was that I had myself convinced that we needed to do the check_and_advance as late as possible in the fsync process, after the metadata had been written. Now that I think about it more, I think you're probably correct. As long as we do the check and advance at some point after doing the write_and_wait, we're fine here and shouldn't violate exactly once semantics on the fsync return. -- Jeff Layton <jlayton@xxxxxxxxxx>