On Thu, Sep 10, 2020 at 01:15:41PM -0400, Mike Snitzer wrote: > > I'll move it to blk_register_queue, which should work just fine. > > That'll work for initial DM table load as part of DM device creation > (dm_setup_md_queue). But it won't account for DM table reloads that > might change underlying devices on a live DM device (done using > __bind). > > Both dm_setup_md_queue() and __bind() call dm_table_set_restrictions() > to set/update queue_limits. It feels like __bind() will need to call a > new block helper to set/update parts of queue_limits (e.g. ra_pages and > io_pages). > > Any chance you're open to factoring out that block function as an > exported symbol for use by blk_register_queue() and code like DM's > __bind()? I agree with the problem statement. OTOH adding an exported helper for two trivial assignments seems a little silly.. For now I'll just keep the open coded ->io_pages assignment in dm. Note that dm doesn't currently update the ->ra_pages value based on the underlying devices, so an incremental patch to do that might be useful as well.
