1config OVERLAY_FS 2 tristate "Overlay filesystem support" 3 help 4 An overlay filesystem combines two filesystems - an 'upper' filesystem 5 and a 'lower' filesystem. When a name exists in both filesystems, the 6 object in the 'upper' filesystem is visible while the object in the 7 'lower' filesystem is either hidden or, in the case of directories, 8 merged with the 'upper' object. 9 10 For more information see Documentation/filesystems/overlayfs.txt 11 12config OVERLAY_FS_REDIRECT_DIR 13 bool "Overlayfs: turn on redirect dir feature by default" 14 depends on OVERLAY_FS 15 help 16 If this config option is enabled then overlay filesystems will use 17 redirects when renaming directories by default. In this case it is 18 still possible to turn off redirects globally with the 19 "redirect_dir=off" module option or on a filesystem instance basis 20 with the "redirect_dir=off" mount option. 21 22 Note, that redirects are not backward compatible. That is, mounting 23 an overlay which has redirects on a kernel that doesn't support this 24 feature will have unexpected results. 25