> nr_pages = (fi.offset + fi.length - 1) / PAGE_SIZE -
> fi.offset / PAGE_SIZE + 1;
> + bio_release_folio(bio, fi.folio, nr_pages);
> }
> }
> EXPORT_SYMBOL_GPL(__bio_release_pages);
> diff --git a/block/blk.h b/block/blk.h
> index 0c8857fe4079..18520b05c6ce 100644
> --- a/block/blk.h
> +++ b/block/blk.h
> @@ -548,6 +548,13 @@ static inline void bio_release_page(struct bio *bio, struct page *page)
> unpin_user_page(page);
> }
>
> +static inline void bio_release_folio(struct bio *bio, struct folio *folio,
> + unsigned long npages)
> +{
> + if (bio_flagged(bio, BIO_PAGE_PINNED))
> + unpin_user_folio(folio, npages);
> +}
This is only used in __bio_release_pages, and given that
__bio_release_pages is only called when BIO_PAGE_PINNED is set there
is no need to check it inside the loop again.
Also this means we know the loop doesn't do anything if mark_dirty is
false, which is another trivial check that can move into
bio_release_pages. As this optimization already applies as-is I'll
send a prep patch for it.
so that we can avoid the npages calculation for the !BIO_PAGE_PINNED
case. Morover having the BIO_PAGE_PINNED knowledge there means we
can skip the entire loop for !BIO_PAGE_PINNED &&
> +/**
> + * unpin_user_folio() - release pages of a folio
> + * @folio: pointer to folio to be released
> + * @npages: number of pages of same folio
> + *
> + * Release npages of the folio
> + */
> +void unpin_user_folio(struct folio *folio, unsigned long npages)
> +{
> + gup_put_folio(folio, npages, FOLL_PIN);
> +}
> +EXPORT_SYMBOL(unpin_user_folio);
Please don't hide a new MM API inside a block patch, but split it out
with a mm prefix.
