On Fri, Oct 21, 2016 at 12:30 PM, Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > On Fri, Oct 21, 2016 at 11:13 AM, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > >> I think it would be a good idea in general to stabilize the overlay ino/dev >> throughout copy-up, same as Miklos suggested to do for directories, to >> all files: >> pure upper uses upper ino + overlayfs dev >> non-pure upper uses lower ino + overlayfs dev > > Making st_ino, st_dev and d_ino behave consistently would be the next big step. > > The above scheme only works if lower and upper are on the same > filesystem. Otherwise there can be collisions between the lower and > upper inode numbers. Perhaps you meant: > > - pure upper uses upper ino + upper dev > - non-pure upper uses lower ino + overlayfs dev > > It works for the single lower layer case, but again breaks if there > are multiple lower layers. And d_ino in a merged directory could > still get us into trouble. And find -xdev would not do what you'd > expect with a "normal" filesystem. > > So there doesn't appear to be any easy solutions to this... > Not for the general case there isn't, but I was actually thinking of the docker case and there is a lot that can be done for the use case of lower and upper on the same fs to make overlayfs more compliant. Since it's quite a common use case, perhaps its worth the special treatment. Amir. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
