Matthew Wilcox <willy@xxxxxxxxxxxxx> writes: > On Wed, Mar 13, 2024 at 12:05:07PM +0100, Andreas Hindborg wrote: >> - Adopted the folio abstraction where applicable > > I don't think this was the correct move. The memory you're managing > with folios is only used for storing the data being stored in the blkdev. > It's not mapped to userspace, it doesn't make use of the flags (locked, > uptodate, writeback, etc), it doesn't need an LRU list, a mapping, > an index, a refcount or memcg. > > I think you should use pages instead of folios to keep a handle on > this memory. Apologies for the confusion; we're in the middle of a > years-long transition from the overly complex and overused struct page > to splitting it into different data types for different purposes. Ok, thanks. I'll swap it back. I was under the impression that using folios also give the advantage that handles are always head pages. No need to worry about head/tail pages. If the driver moves to use higher order pages for larger block sizes, would it then make sense with folios, or are page still preferred? > More detail on this here, if you're interested: > https://kernelnewbies.org/MatthewWilcox/Memdescs Thanks, that is useful. Best regards, Andreas
