On Thu, Aug 22, 2024 at 01:41:49AM GMT, Al Viro wrote: > Once we'd opened the file, nd->path and file->f_path have the > same contents. Rather than having both pinned and nd->path > dropped by terminate_walk(), let's have them share the > references from the moment when FMODE_OPENED is set and > clear nd->path just before the terminate_walk() in such case. > > To do that, we > * add a variant of vfs_open() that does *not* do conditional > path_get() (vfs_open_borrow()); use it in do_open(). > * don't grab f->f_path.mnt in finish_open() - only > f->f_path.dentry. Have atomic_open() drop the child dentry > in FMODE_OPENED case and return f->path.dentry without grabbing it. > * adjust vfs_tmpfile() for finish_open() change (it > is called from ->tmpfile() instances). > * make do_o_path() use vfs_open_borrow(), collapse path_put() > there with the conditional path_get() we would've get in vfs_open(). > * in FMODE_OPENED case clear nd->path before calling > terminate_walk(). > > Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx> > --- Reviewed-by: Christian Brauner <brauner@xxxxxxxxxx>
