On Fri, Nov 07, 2014 at 11:09:59AM -0800, Christoph Hellwig wrote: > The overlayfs merge introduces a new rename flag to create to whiteouts. > Should be a fairly easy to implement. > > Miklos, do you have any good documentation and/or test cases for this? So overlayfs uses some weird char dev hack to implement whiteout inodes in directories? Why do we need a whiteout inode on disk? what information is actually stored in the whiteout inode that overlayfs actually needs? Only readdir and lookup care about whiteouts, and AFAICT nothing of the inode is ever used except checking the chrdev/whiteoutdev hack via ovl_is_whiteout(dentry). Indeed, whatever happened to just storing the whiteout in the dirent via DT_WHT and using that information on lookup in the lower filesystem to mark the dentry returned appropriately without needing to lookup a real inode? Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
