Commit 9774b391 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: mark __bio_try_merge_page static 



Mark __bio_try_merge_page static and move it up a bit to avoid the need
for a forward declaration.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20211012161804.991559-7-hch@lst.de


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 9a6083be

block/bio.c

+38 −39
Original line number Diff line number Diff line
@@ -808,6 +808,44 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, 
	return (bv->bv_page + bv_end / PAGE_SIZE) == (page + off / PAGE_SIZE);

}



/**

 * __bio_try_merge_page - try appending data to an existing bvec.

 * @bio: destination bio

 * @page: start page to add

 * @len: length of the data to add

 * @off: offset of the data relative to @page

 * @same_page: return if the segment has been merged inside the same page

 *

 * Try to add the data at @page + @off to the last bvec of @bio.  This is a

 * useful optimisation for file systems with a block size smaller than the

 * page size.

 *

 * Warn if (@len, @off) crosses pages in case that @same_page is true.

 *

 * Return %true on success or %false on failure.

 */

static bool __bio_try_merge_page(struct bio *bio, struct page *page,

		unsigned int len, unsigned int off, bool *same_page)

{

	if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))

		return false;



	if (bio->bi_vcnt > 0) {

		struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];



		if (page_is_mergeable(bv, page, len, off, same_page)) {

			if (bio->bi_iter.bi_size > UINT_MAX - len) {

				*same_page = false;

				return false;

			}

			bv->bv_len += len;

			bio->bi_iter.bi_size += len;

			return true;

		}

	}

	return false;

}



/*

 * Try to merge a page into a segment, while obeying the hardware segment

 * size limit.  This is not for normal read/write bios, but for passthrough
@@ -939,45 +977,6 @@ int bio_add_zone_append_page(struct bio *bio, struct page *page, 
}

EXPORT_SYMBOL_GPL(bio_add_zone_append_page);



/**

 * __bio_try_merge_page - try appending data to an existing bvec.

 * @bio: destination bio

 * @page: start page to add

 * @len: length of the data to add

 * @off: offset of the data relative to @page

 * @same_page: return if the segment has been merged inside the same page

 *

 * Try to add the data at @page + @off to the last bvec of @bio.  This is a

 * useful optimisation for file systems with a block size smaller than the

 * page size.

 *

 * Warn if (@len, @off) crosses pages in case that @same_page is true.

 *

 * Return %true on success or %false on failure.

 */

bool __bio_try_merge_page(struct bio *bio, struct page *page,

		unsigned int len, unsigned int off, bool *same_page)

{

	if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))

		return false;



	if (bio->bi_vcnt > 0) {

		struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1];



		if (page_is_mergeable(bv, page, len, off, same_page)) {

			if (bio->bi_iter.bi_size > UINT_MAX - len) {

				*same_page = false;

				return false;

			}

			bv->bv_len += len;

			bio->bi_iter.bi_size += len;

			return true;

		}

	}

	return false;

}

EXPORT_SYMBOL_GPL(__bio_try_merge_page);



/**

 * __bio_add_page - add page(s) to a bio in a new segment

 * @bio: destination bio

include/linux/bio.h

+0 −2
Original line number Diff line number Diff line
@@ -425,8 +425,6 @@ extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, 
			   unsigned int, unsigned int);

int bio_add_zone_append_page(struct bio *bio, struct page *page,

			     unsigned int len, unsigned int offset);

bool __bio_try_merge_page(struct bio *bio, struct page *page,

		unsigned int len, unsigned int off, bool *same_page);

void __bio_add_page(struct bio *bio, struct page *page,

		unsigned int len, unsigned int off);

int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);