On Mon, Jun 12, 2023 at 09:28:40AM +0300, Amir Goldstein wrote: > 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? Most users of file_dentry are inside file systems and will never see the overlayfs path. > > 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(). Yeah, that makes this comment kinda irrelevant.
