Commit e4581105 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: rename __bio_add_pc_page to bio_add_hw_page 



Rename __bio_add_pc_page() to bio_add_hw_page() and explicitly pass in a
max_sectors argument.

This max_sectors argument can be used to specify constraints from the
hardware.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
[ jth: rebased and made public for blk-map.c ]
Signed-off-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarDaniel Wagner <dwagner@suse.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarHannes Reinecke <hare@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 02992df8

block/bio.c

+40 −25
Original line number Diff line number Diff line
@@ -748,9 +748,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, 
	return true;

}



static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio,

		struct page *page, unsigned len, unsigned offset,

		bool *same_page)

/*

 * 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

 * or Zone Append operations that we can't split.

 */

static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio,

				 struct page *page, unsigned len,

				 unsigned offset, bool *same_page)

{

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

	unsigned long mask = queue_segment_boundary(q);
@@ -765,38 +770,32 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, 
}



/**

 *	__bio_add_pc_page	- attempt to add page to passthrough bio

 * bio_add_hw_page - attempt to add a page to a bio with hw constraints

 * @q: the target queue

 * @bio: destination bio

 * @page: page to add

 * @len: vec entry length

 * @offset: vec entry offset

 *	@same_page: return if the merge happen inside the same page

 *

 *	Attempt to add a page to the bio_vec maplist. This can fail for a

 *	number of reasons, such as the bio being full or target block device

 *	limitations. The target block device must allow bio's up to PAGE_SIZE,

 *	so it is always possible to add a single page to an empty bio.

 * @max_sectors: maximum number of sectors that can be added

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

 *

 *	This should only be used by passthrough bios.

 * Add a page to a bio while respecting the hardware max_sectors, max_segment

 * and gap limitations.

 */

int __bio_add_pc_page(struct request_queue *q, struct bio *bio,

int bio_add_hw_page(struct request_queue *q, struct bio *bio,

		struct page *page, unsigned int len, unsigned int offset,

		bool *same_page)

		unsigned int max_sectors, bool *same_page)

{

	struct bio_vec *bvec;



	/*

	 * cloned bio must not modify vec list

	 */

	if (unlikely(bio_flagged(bio, BIO_CLONED)))

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

		return 0;



	if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q))

	if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors)

		return 0;



	if (bio->bi_vcnt > 0) {

		if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page))

		if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page))

			return len;



		/*
@@ -823,11 +822,27 @@ int __bio_add_pc_page(struct request_queue *q, struct bio *bio, 
	return len;

}



/**

 * bio_add_pc_page	- attempt to add page to passthrough bio

 * @q: the target queue

 * @bio: destination bio

 * @page: page to add

 * @len: vec entry length

 * @offset: vec entry offset

 *

 * Attempt to add a page to the bio_vec maplist. This can fail for a

 * number of reasons, such as the bio being full or target block device

 * limitations. The target block device must allow bio's up to PAGE_SIZE,

 * so it is always possible to add a single page to an empty bio.

 *

 * This should only be used by passthrough bios.

 */

int bio_add_pc_page(struct request_queue *q, struct bio *bio,

		struct page *page, unsigned int len, unsigned int offset)

{

	bool same_page = false;

	return __bio_add_pc_page(q, bio, page, len, offset, &same_page);

	return bio_add_hw_page(q, bio, page, len, offset,

			queue_max_hw_sectors(q), &same_page);

}

EXPORT_SYMBOL(bio_add_pc_page);

block/blk-map.c

+3 −2
Original line number Diff line number Diff line
@@ -257,6 +257,7 @@ out_bmd: 
static struct bio *bio_map_user_iov(struct request_queue *q,

		struct iov_iter *iter, gfp_t gfp_mask)

{

	unsigned int max_sectors = queue_max_hw_sectors(q);

	int j;

	struct bio *bio;

	int ret;
@@ -294,8 +295,8 @@ static struct bio *bio_map_user_iov(struct request_queue *q, 
				if (n > bytes)

					n = bytes;



				if (!__bio_add_pc_page(q, bio, page, n, offs,

						&same_page)) {

				if (!bio_add_hw_page(q, bio, page, n, offs,

						     max_sectors, &same_page)) {

					if (same_page)

						put_page(page);

					break;

block/blk.h

+2 −2
Original line number Diff line number Diff line
@@ -452,8 +452,8 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size) 


struct request_queue *__blk_alloc_queue(int node_id);



int __bio_add_pc_page(struct request_queue *q, struct bio *bio,

int bio_add_hw_page(struct request_queue *q, struct bio *bio,

		struct page *page, unsigned int len, unsigned int offset,

		bool *same_page);

		unsigned int max_sectors, bool *same_page);



#endif /* BLK_INTERNAL_H */

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