On Mon, Jun 12, 2023 at 7:36 AM Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > On Sun, Jun 11, 2023 at 04:27:31PM +0300, Amir Goldstein wrote: > > Overlayfs knows the real path of underlying dentries. Add an optional > > struct vfsmount out argument to ->d_real(), so callers could compose the > > real path. > > > > Add a helper f_real_path() that uses this new interface to return the > > real path of f_inode, for overlayfs internal files whose f_path if a > > "fake" overlayfs path and f_inode is the underlying real inode. > > I really don't like this ->d_real nagic. Most callers of it > really can't ever be on overlayfs. Which callers are you referring to? > So I'd suggest we do an audit > of the callers of file_dentry and drop all the pointless ones > first, and improve the documentation on when to use it. Well, v3 is trying to reduce ->d_real() magic and the step after introducing the alternative path container is to convert file_dentry() to use the stored real_path instead of ->d_real(). But I agree that the documentation about this black magic is missing. Will try to improve that with the move to the "fake" file container. Thanks, Amir.
