On Tue, May 26, 2020 at 01:51:15PM -0600, Jens Axboe wrote: > Normally waiting for a page to become unlocked, or locking the page, > requires waiting for IO to complete. Add support for lock_page_async() > and wait_on_page_locked_async(), which are callback based instead. This wait_on_page_locked_async() is actually in the next patch, requiring some back and forth to review. I wonder if this and the next patch could be merged to have the new API and callers introduced together? > allows a caller to get notified when a page becomes unlocked, rather > than wait for it. > > We add a new iocb field, ki_waitq, to pass in the necessary data for this > to happen. We can unionize this with ki_cookie, since that is only used > for polled IO. Polled IO can never co-exist with async callbacks, as it is > (by definition) polled completions. struct wait_page_key is made public, > and we define struct wait_page_async as the interface between the caller > and the core. > > Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
