[$] A way to do atomic writes

<p>Finding a way for applications to do atomic writes to files, so that eitherthe old or new data is present after a crash and not a combination of thetwo, was the topic of a session led by Christoph Hellwig at the 2019 Linux Storage, Filesystem, andMemory-Management Summit (LSFMM).Application developers hate the fact that when they update files in place,a crash can leave them with old or new data-or sometimes a combination ofboth. He discussed some implementation ideasthat he has for atomic writes for XFS and wanted to see what the otherfilesystem developers thought about it.