Commit aa261f20 authored by Bart Van Assche's avatar Bart Van Assche Committed by Jens Axboe
Browse files

block: Constify most queue limits pointers 



Document which functions do not modify the queue limits.

Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: default avatarBart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20221025191755.1711437-3-bvanassche@acm.org


Reviewed-by: default avatarKeith Busch <kbusch@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b179c98f

block/blk-map.c

+1 −1
Original line number Diff line number Diff line
@@ -555,7 +555,7 @@ static int blk_rq_map_user_bvec(struct request *rq, const struct iov_iter *iter) 
	size_t nr_iter = iov_iter_count(iter);

	size_t nr_segs = iter->nr_segs;

	struct bio_vec *bvecs, *bvprvp = NULL;

	struct queue_limits *lim = &q->limits;

	const struct queue_limits *lim = &q->limits;

	unsigned int nsegs = 0, bytes = 0;

	struct bio *bio;

	size_t i;

block/blk-merge.c

+16 −13
Original line number Diff line number Diff line
@@ -100,12 +100,13 @@ static inline bool req_gap_front_merge(struct request *req, struct bio *bio) 
 * is defined as 'unsigned int', meantime it has to be aligned to with the

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

 */

static unsigned int bio_allowed_max_sectors(struct queue_limits *lim)

static unsigned int bio_allowed_max_sectors(const struct queue_limits *lim)

{

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

}



static struct bio *bio_split_discard(struct bio *bio, struct queue_limits *lim,

static struct bio *bio_split_discard(struct bio *bio,

				     const struct queue_limits *lim,

				     unsigned *nsegs, struct bio_set *bs)

{

	unsigned int max_discard_sectors, granularity;
@@ -146,7 +147,8 @@ static struct bio *bio_split_discard(struct bio *bio, struct queue_limits *lim, 
}



static struct bio *bio_split_write_zeroes(struct bio *bio,

		struct queue_limits *lim, unsigned *nsegs, struct bio_set *bs)

					  const struct queue_limits *lim,

					  unsigned *nsegs, struct bio_set *bs)

{

	*nsegs = 0;

	if (!lim->max_write_zeroes_sectors)
@@ -165,7 +167,7 @@ static struct bio *bio_split_write_zeroes(struct bio *bio, 
 * aligned to a physical block boundary.

 */

static inline unsigned get_max_io_size(struct bio *bio,

		struct queue_limits *lim)

				       const struct queue_limits *lim)

{

	unsigned pbs = lim->physical_block_size >> SECTOR_SHIFT;

	unsigned lbs = lim->logical_block_size >> SECTOR_SHIFT;
@@ -184,7 +186,7 @@ static inline unsigned get_max_io_size(struct bio *bio, 
	return max_sectors & ~(lbs - 1);

}



static inline unsigned get_max_segment_size(struct queue_limits *lim,

static inline unsigned get_max_segment_size(const struct queue_limits *lim,

		struct page *start_page, unsigned long offset)

{

	unsigned long mask = lim->seg_boundary_mask;
@@ -219,9 +221,9 @@ static inline unsigned get_max_segment_size(struct queue_limits *lim, 
 * *@nsegs segments and *@sectors sectors would make that bio unacceptable for

 * the block driver.

 */

static bool bvec_split_segs(struct queue_limits *lim, const struct bio_vec *bv,

		unsigned *nsegs, unsigned *bytes, unsigned max_segs,

		unsigned max_bytes)

static bool bvec_split_segs(const struct queue_limits *lim,

		const struct bio_vec *bv, unsigned *nsegs, unsigned *bytes,

		unsigned max_segs, unsigned max_bytes)

{

	unsigned max_len = min(max_bytes, UINT_MAX) - *bytes;

	unsigned len = min(bv->bv_len, max_len);
@@ -267,7 +269,7 @@ static bool bvec_split_segs(struct queue_limits *lim, const struct bio_vec *bv, 
 * responsible for ensuring that @bs is only destroyed after processing of the

 * split bio has finished.

 */

static struct bio *bio_split_rw(struct bio *bio, struct queue_limits *lim,

static struct bio *bio_split_rw(struct bio *bio, const struct queue_limits *lim,

		unsigned *segs, struct bio_set *bs, unsigned max_bytes)

{

	struct bio_vec bv, bvprv, *bvprvp = NULL;
@@ -331,7 +333,8 @@ static struct bio *bio_split_rw(struct bio *bio, struct queue_limits *lim, 
 * The split bio is allocated from @q->bio_split, which is provided by the

 * block layer.

 */

struct bio *__bio_split_to_limits(struct bio *bio, struct queue_limits *lim,

struct bio *__bio_split_to_limits(struct bio *bio,

				  const struct queue_limits *lim,

				  unsigned int *nr_segs)

{

	struct bio_set *bs = &bio->bi_bdev->bd_disk->bio_split;
@@ -377,7 +380,7 @@ struct bio *__bio_split_to_limits(struct bio *bio, struct queue_limits *lim, 
 */

struct bio *bio_split_to_limits(struct bio *bio)

{

	struct queue_limits *lim = &bdev_get_queue(bio->bi_bdev)->limits;

	const struct queue_limits *lim = &bdev_get_queue(bio->bi_bdev)->limits;

	unsigned int nr_segs;



	if (bio_may_exceed_limits(bio, lim))

block/blk-settings.c

+3 −3
Original line number Diff line number Diff line
@@ -481,7 +481,7 @@ void blk_queue_io_opt(struct request_queue *q, unsigned int opt) 
}

EXPORT_SYMBOL(blk_queue_io_opt);



static int queue_limit_alignment_offset(struct queue_limits *lim,

static int queue_limit_alignment_offset(const struct queue_limits *lim,

		sector_t sector)

{

	unsigned int granularity = max(lim->physical_block_size, lim->io_min);
@@ -491,8 +491,8 @@ static int queue_limit_alignment_offset(struct queue_limits *lim, 
	return (granularity + lim->alignment_offset - alignment) % granularity;

}



static unsigned int queue_limit_discard_alignment(struct queue_limits *lim,

		sector_t sector)

static unsigned int queue_limit_discard_alignment(

		const struct queue_limits *lim, sector_t sector)

{

	unsigned int alignment, granularity, offset;

block/blk.h

+6 −5
Original line number Diff line number Diff line
@@ -104,7 +104,7 @@ static inline bool biovec_phys_mergeable(struct request_queue *q, 
	return true;

}



static inline bool __bvec_gap_to_prev(struct queue_limits *lim,

static inline bool __bvec_gap_to_prev(const struct queue_limits *lim,

		struct bio_vec *bprv, unsigned int offset)

{

	return (offset & lim->virt_boundary_mask) ||
@@ -115,7 +115,7 @@ static inline bool __bvec_gap_to_prev(struct queue_limits *lim, 
 * Check if adding a bio_vec after bprv with offset would create a gap in

 * the SG list. Most drivers don't care about this, but some do.

 */

static inline bool bvec_gap_to_prev(struct queue_limits *lim,

static inline bool bvec_gap_to_prev(const struct queue_limits *lim,

		struct bio_vec *bprv, unsigned int offset)

{

	if (!lim->virt_boundary_mask)
@@ -297,7 +297,7 @@ ssize_t part_timeout_store(struct device *, struct device_attribute *, 
				const char *, size_t);



static inline bool bio_may_exceed_limits(struct bio *bio,

		struct queue_limits *lim)

					 const struct queue_limits *lim)

{

	switch (bio_op(bio)) {

	case REQ_OP_DISCARD:
@@ -320,7 +320,8 @@ static inline bool bio_may_exceed_limits(struct bio *bio, 
		bio->bi_io_vec->bv_len + bio->bi_io_vec->bv_offset > PAGE_SIZE;

}



struct bio *__bio_split_to_limits(struct bio *bio, struct queue_limits *lim,

struct bio *__bio_split_to_limits(struct bio *bio,

				  const struct queue_limits *lim,

				  unsigned int *nr_segs);

int ll_back_merge_fn(struct request *req, struct bio *bio,

		unsigned int nr_segs);