Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> --- Documentation/filesystems/overlayfs.txt | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/Documentation/filesystems/overlayfs.txt b/Documentation/filesystems/overlayfs.txt index 634d03e..c9e884b 100644 --- a/Documentation/filesystems/overlayfs.txt +++ b/Documentation/filesystems/overlayfs.txt @@ -21,12 +21,19 @@ from accessing the corresponding object from the original filesystem. This is most obvious from the 'st_dev' field returned by stat(2). While directories will report an st_dev from the overlay-filesystem, -all non-directory objects will report an st_dev from the lower or +non-directory objects may report an st_dev from the lower filesystem or upper filesystem that is providing the object. Similarly st_ino will only be unique when combined with st_dev, and both of these can change over the lifetime of a non-directory object. Many applications and tools ignore these values and will not be affected. +In the special case of all overlay layers on the same underlying +filesystem, all objects will report an st_dev from the overlay +filesystem and st_ino from the underlying filesystem. This will +make the overlay mount more compliant with filesystem scanners and +overlay objects will be distinguishable from the corresponding +objects in the original filesystem. + Upper and Lower --------------- -- 2.7.4
