On Fri, Sep 15, 2023 at 10:51:12PM +0100, Matthew Wilcox wrote: > On Fri, Sep 15, 2023 at 02:32:44PM -0700, Luis Chamberlain wrote: > > However, an issue is that disabling CONFIG_BUFFER_HEAD in practice is not viable > > for many Linux distributions since it also means disabling support for most > > filesystems other than btrfs and XFS. So we either support larger order folios > > on buffer-heads, or we draw up a solution to enable co-existence. Since at LSFMM > > 2023 it was decided we would not support larger order folios on buffer-heads, > > Um, I didn't agree to that. Coverage on sunsetting buffer-heads talk by LWN: https://lwn.net/Articles/931809/ "the apparent conclusion from the session: the buffer-head layer will be converted to use folios internally while minimizing changes visible to the filesystems using it. Only single-page folios will be used within this new buffer-head layer. Any other desires, he said, can be addressed later after this problem has been solved." And so I think we're at the later part of this. I'm happy to see efforts for buffer-heads support with large order folio support, and so at this point I think it would be wise to look for commonalities and colalborate on what things could / should be shared. Luis