On Fri, 27 Oct 2023 at 15:17, Josef Bacik <josef@xxxxxxxxxxxxxx> wrote: > I have to support this file system in the real world, with real world stupidity > happening that I can't control. I wholeheartedly agree that the statx fields > are not a direct fix, it's a comprimise. It's a way forward to let the users > who care about the distinction be able to get the information they need to make > better decisions about what to do when they run into btrfs's weirdness. It > doesn't solve the st_dev problem today, or even for a couple of years, but it > gives us a way to eventually change the st_dev thing. Thanks, This is very similar to the problem that overlayfs is trying hard to work around: unifying more than one st_ino namespace into a single st_ino namespace. Btrfs used st_dev, overlayfs is using the high bits of st_ino. Both of these are hacks. Adding one more 64bit field doesn't look like a proper solution: now overlayfs will have to fit multiple 128bit namespace into a single 128bit namespace. Not sure what's the right answer, but file handles come to mind, since they have some nice properties: - not reused after unlink - variable length Thanks, Miklos
