On Mon, Mar 6, 2017 at 4:59 PM, J. R. Okajima <hooanon05g@xxxxxxxxx> wrote: > Amir Goldstein: >> Factor out some common vfs bits from do_tmpfile() >> to be used by overlayfs for concurrent copy up. > > Hmm, just to copy-up. > I have no objection this factoring-out, but do you have any specific > reason for overlayfs NOT to support i_op->tmpfile()? No reason. Just someone has to do the leg work. > > If you try supporting it in the future, then the parameter open_flag may > become a problem. I guess that you will make ovl_tmpfile() (currently > not exist) to call vfs_tmpfile(), and pass dummy 0 as open_flag as > overlayfs copy-up does. But such dummy parameter will make the created > tmpfile un-linkable by a user I am afraid. > I don't think that's going to be a problem. ovl_link() can probably make sure that I_LINKABLE is propagated to upper inode before calling vfs_link() for a tmpfile.
