Commit fa0bdd45 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: add a BIO_MAX_SIZE constant and use it 



Currently the only constant for the maximum bio size is BIO_MAX_SECTORS,
which is in units of 512-byte sectors, but a lot of user need a byte
limit.

Add a BIO_MAX_SIZE constant, redefine BIO_MAX_SECTORS in terms of it, and
switch all bio-related uses of UINT_MAX for the maximum size to use the
symbolic names instead.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Reviewed-by: default avatarAnuj Gupta <anuj20.g@samsung.com>
Reviewed-by: default avatarJohannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: default avatarDamien Le Moal <dlemoal@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 7c746eb7

block/bio.c

+5 −5
Original line number Diff line number Diff line
@@ -924,7 +924,7 @@ static inline bool bio_full(struct bio *bio, unsigned len) 
{

	if (bio->bi_vcnt >= bio->bi_max_vecs)

		return true;

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

	if (bio->bi_iter.bi_size > BIO_MAX_SIZE - len)

		return true;

	return false;

}
@@ -1030,7 +1030,7 @@ int bio_add_page(struct bio *bio, struct page *page, 
{

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

		return 0;

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

	if (bio->bi_iter.bi_size > BIO_MAX_SIZE - len)

		return 0;



	if (bio->bi_vcnt > 0) {
@@ -1057,7 +1057,7 @@ void bio_add_folio_nofail(struct bio *bio, struct folio *folio, size_t len, 
{

	unsigned long nr = off / PAGE_SIZE;



	WARN_ON_ONCE(len > UINT_MAX);

	WARN_ON_ONCE(len > BIO_MAX_SIZE);

	__bio_add_page(bio, folio_page(folio, nr), len, off % PAGE_SIZE);

}

EXPORT_SYMBOL_GPL(bio_add_folio_nofail);
@@ -1081,7 +1081,7 @@ bool bio_add_folio(struct bio *bio, struct folio *folio, size_t len, 
{

	unsigned long nr = off / PAGE_SIZE;



	if (len > UINT_MAX)

	if (len > BIO_MAX_SIZE)

		return false;

	return bio_add_page(bio, folio_page(folio, nr), len, off % PAGE_SIZE) > 0;

}
@@ -1238,7 +1238,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) 
		extraction_flags |= ITER_ALLOW_P2PDMA;



	size = iov_iter_extract_pages(iter, &pages,

				      UINT_MAX - bio->bi_iter.bi_size,

				      BIO_MAX_SIZE - bio->bi_iter.bi_size,

				      nr_pages, extraction_flags, &offset);

	if (unlikely(size <= 0))

		return size ? size : -EFAULT;

block/blk-lib.c

+4 −5
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ static sector_t bio_discard_limit(struct block_device *bdev, sector_t sector) 
	 * Align the bio size to the discard granularity to make splitting the bio

	 * at discard granularity boundaries easier in the driver if needed.

	 */

	return round_down(UINT_MAX, discard_granularity) >> SECTOR_SHIFT;

	return round_down(BIO_MAX_SIZE, discard_granularity) >> SECTOR_SHIFT;

}



struct bio *blk_alloc_discard_bio(struct block_device *bdev,
@@ -107,8 +107,7 @@ static sector_t bio_write_zeroes_limit(struct block_device *bdev) 
{

	sector_t bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;



	return min(bdev_write_zeroes_sectors(bdev),

		(UINT_MAX >> SECTOR_SHIFT) & ~bs_mask);

	return min(bdev_write_zeroes_sectors(bdev), BIO_MAX_SECTORS & ~bs_mask);

}



/*
@@ -337,8 +336,8 @@ int blkdev_issue_secure_erase(struct block_device *bdev, sector_t sector, 
	int ret = 0;



	/* make sure that "len << SECTOR_SHIFT" doesn't overflow */

	if (max_sectors > UINT_MAX >> SECTOR_SHIFT)

		max_sectors = UINT_MAX >> SECTOR_SHIFT;

	if (max_sectors > BIO_MAX_SECTORS)

		max_sectors = BIO_MAX_SECTORS;

	max_sectors &= ~bs_mask;



	if (max_sectors == 0)

block/blk-merge.c

+4 −4
Original line number Diff line number Diff line
@@ -95,13 +95,13 @@ static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 
}



/*

 * The max size one bio can handle is UINT_MAX becasue bvec_iter.bi_size

 * is defined as 'unsigned int', meantime it has to be aligned to with the

 * The maximum size that a bio can fit has to be aligned down to the

 * logical block size, which is the minimum accepted unit by hardware.

 */

static unsigned int bio_allowed_max_sectors(const struct queue_limits *lim)

{

	return round_down(UINT_MAX, lim->logical_block_size) >> SECTOR_SHIFT;

	return round_down(BIO_MAX_SIZE, lim->logical_block_size) >>

			SECTOR_SHIFT;

}



/*
@@ -502,7 +502,7 @@ unsigned int blk_recalc_rq_segments(struct request *rq) 


	rq_for_each_bvec(bv, rq, iter)

		bvec_split_segs(&rq->q->limits, &bv, &nr_phys_segs, &bytes,

				UINT_MAX, UINT_MAX);

				UINT_MAX, BIO_MAX_SIZE);

	return nr_phys_segs;

}

include/linux/blk_types.h

+2 −1
Original line number Diff line number Diff line
@@ -281,7 +281,8 @@ struct bio { 
};



#define BIO_RESET_BYTES		offsetof(struct bio, bi_max_vecs)

#define BIO_MAX_SECTORS		(UINT_MAX >> SECTOR_SHIFT)

#define BIO_MAX_SIZE		UINT_MAX /* max value of bi_iter.bi_size */

#define BIO_MAX_SECTORS		(BIO_MAX_SIZE >> SECTOR_SHIFT)



static inline struct bio_vec *bio_inline_vecs(struct bio *bio)

{