Re: [PATCH v9 0/3] mm/gup: disallow GUP writing to file-backed mappings by default

On Wed, May 17, 2023 at 08:40:26AM +0100, Lorenzo Stoakes wrote:

quoted

I'm not sure what you mean by "total flexibility" here. In my opinion it is
also about how HW performs checksumming etc.

I mean to say *_ops allow a lot of flexibility in how things are
handled. Certainly checksumming is a great example but in theory an
arbitrary filesystem could be doing, well, anything and always assuming
that only userland mappings should be modifying the underlying data.

File systems need a wait to track when a page is dirtied so that it can
be written back.  Not much to do with flexbility.