On Sat, Sep 10, 2022 at 08:50:56AM +0200, Christoph Hellwig wrote: > btrfs compressed reads try to always read the entire compressed chunk, > even if only a subset is requested. Currently this is covered by the > magic PSI accounting underneath submit_bio, but that is about to go > away. Instead add manual psi_memstall_{enter,leave} annotations. > > Note that for readahead this really should be using readahead_expand, > but the additionals reads are also done for plain ->read_folio where > readahead_expand can't work, so this overall logic is left as-is for > now. > > Signed-off-by: Christoph Hellwig <hch@xxxxxx> Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>