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See http://www.infradead.org/rpr.html X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 0472F140005 X-Stat-Signature: q3gicmgrextobai4ia96kebfi9omw5ck X-HE-Tag: 1685089572-264829 X-HE-Meta: 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 QTLH6teU 8J5ol6SFJQYkGDowoY7KnHTtglWosN6Y1lVp7mfA3h/y/e9SI9hmWKcY4lphXMIufSDNUuGvWg23RGXxKG5X7mz8a+8J3kq0KQbJH6PFDRJue7KnRr53d9kFs7mg6L5E6GGGHj8oXZbpV84ScrhoUQH3uIaBTpKmCkXoAMBlOmkZevwGB7wJpsMUhVuuhkvJtFCZxNqX2OJb7RKQpVmsggXnlNYPNTIaHrPtJHalWcEDbC6T1X4iUREQy/ZbXyQaWmgtkTbDfyNnu0ZzCkdoB9nSZ92Bkq+M0Wnx87zPlCQ4F7RkWb/EdlzGdP5uF7fQiVhnrqaBEhZITxh9wn++/bZ8IswFD86vOlHFdLtGS1IeVHgRSJx/SKNlBe2ZKzx6mMHS1g7NdN7DneEFs/jeG6D3qguPEE0GOkIzq6k/XaU8gyXVU0oM5jHwV+g== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Thu, May 25, 2023 at 11:39:53PM +0100, David Howells wrote: > Change the old block-based direct-I/O code to use iov_iter_extract_pages() > to pin user pages or leave kernel pages unpinned rather than taking refs > when submitting bios. > > This makes use of the preceding patches to not take pins on the zero page > (thereby allowing insertion of zero pages in with pinned pages) and to get > additional pins on pages, allowing an extracted page to be used in multiple > bios without having to re-extract it. I'm not seeing where we skip the unpin of the zero page, as commented in patch 1 (but maybe I'm not reviewing carefully enough as I'm at a conference right now). Otherwise my only rather cosmetic comment right now is that I'd called the "need_unpin" member is_pinned.