Re: [PATCH v8 03/10] mm: Provide a helper to drop a pin/ref on a page

From: Christoph Hellwig
Date: Tue Jan 24 2023 - 09:53:16 EST


On Tue, Jan 24, 2023 at 02:41:33PM +0000, David Howells wrote:
> Yes. Christoph insisted that the bio conversion patch be split up. That
> means there's an interval where you can get FOLL_GET from that.

The only place where we have both is in the block layer. It never gets
set by bio_set_cleanup_mode.

Instead we can just keep using put_page dirctly for the BIO_PAGE_REFFED
case in the callers of bio_release_page and in bio_release_pages itself,
and then do away with bio_to_gup_flags and bio_release_page entirely.