On Tue, Jan 30, 2024 at 04:42:07PM +0800, zhaoyang.huang wrote: > +static __maybe_unused > +bool act_bio_add_folio(struct bio *bio, struct folio *folio, size_t len, > + size_t off) No, stop this. What the filesystem needs to do is not s/bio_add_folio/act_bio_add_folio/. There needs to be an API to set the bio prio; something like: bio_set_active_prio(bio, folio); and then you can do whatever gunk is needed in bio_set_active_prio() to end up calling bio_set_prio().