On Fri, Sep 08, 2017 at 09:25:43AM +1000, Dave Chinner wrote: > > Okay, so other ideas (which you have also probably already though of) include: > > > > 1) Just return -EBUSY if anyone tries to change the DAX flag of an inode with > > open mappings or any open file handles. > > You have to have an open fd to change the flag. :) What if we only allow the S_DAX flag to be *set*, when i_size and i_blocks is zero? We could also require that only one file descriptor be open against the inode, and that it be opened O_RDONLY. - Ted
