On Fri, Nov 24, 2023 at 08:11:41AM +0000, Al Viro wrote: > On Fri, Nov 24, 2023 at 09:37:16AM +0200, Amir Goldstein wrote: > > > Since you like pre-git archeology... > > > > Mind digging up what this comment in fs.h is about: > > > > /* needed for stackable file system support */ > > extern loff_t default_llseek(struct file *file, loff_t offset, int whence); > > Umm... I think it was about ecryptfs and its ilk, but it was a long > time ago... > > <looks> > > 2.3.99pre6, along with exporting it: > -/* for stackable file systems (lofs, wrapfs, etc.) */ > -EXPORT_SYMBOL(add_to_page_cache); > +/* for stackable file systems (lofs, wrapfs, cryptfs, etc.) */ > +EXPORT_SYMBOL(default_llseek); > +EXPORT_SYMBOL(dentry_open); > > Back then ->llseek == NULL used to mean default_llseek; that had > been changed much later. And that was before vfs_llseek() as well, > so any layered filesystem had to open-code it - which required > default_llseek(). > > The comment is certainly stale, though - stackable filesystems do *not* > need it (vfs_llseek() is there), but every file_operation that used > to have NULL ->llseek does. > > > Or we can just remove it without digging up what the comment used > > to refer to ;) > > Too late - it will have to be removed with that ;-) BTW, there's this, covering more than just BK times: git://git.kernel.org/pub/scm/linux/kernel/git/history/history.git/
