From: Jeff Layton [mailto:jlayton@xxxxxxxxxxxxxxx] > On Thu, 2017-06-29 at 10:11 -0700, Darrick J. Wong wrote: > > On Thu, Jun 29, 2017 at 09:19:48AM -0400, jlayton@xxxxxxxxxx wrote: > > > +Handling errors during writeback > > > +-------------------------------- > > > +Most applications that utilize the pagecache will periodically call > > > +fsync to ensure that data written has made it to the backing store. > > > > /me wonders if this sentence ought to be worded more strongly, e.g. > > > > "Applications that utilize the pagecache must call a data > > synchronization syscall such as fsync, fdatasync, or msync to ensure > > that data written has made it to the backing store." > > Well...only if they care about the data. There are some that don't. :) Also, applications don't "utilize the pagecache"; filesystems use the pagecache. Applications may or may not use cached I/O. How about this: Applications which care about data integrity and use cached I/O will periodically call fsync(), msync() or fdatasync() to ensure that their data is durable. > What should we do about sync_file_range here? It doesn't currently call > any filesystem operations directly, so we don't have a good way to make > it selectively use errseq_t handling there. > > I could resurrect the FS_* flag for that, though I don't really like > that. Should I just go ahead and convert it over to use errseq_t under > the theory that most callers will eventually want that anyway? I think so.
