Re: [PATCH 2/7] block: add a new helper bdev_{is_zone_start, offset_from_zone_start}

Damien Le Moal
2023-01-06T11:01:05Z

On 1/6/23 17:33, Pankaj Raghav wrote:
> Instead of open coding to check for zone start, add a helper to improve
> readability and store the logic in one place.
>
> bdev_offset_from_zone_start() will be used later in the series.
>
> Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
> ---
> block/blk-core.c | 2 +-
> block/blk-zoned.c | 4 ++--
> include/linux/blkdev.h | 18 ++++++++++++++++++
> 3 files changed, 21 insertions(+), 3 deletions(-)
>
> diff --git a/block/blk-core.c b/block/blk-core.c
> index 9321767470dc..0405b3144e7a 100644
> --- a/block/blk-core.c
> +++ b/block/blk-core.c
> @@ -573,7 +573,7 @@ static inline blk_status_t blk_check_zone_append(struct request_queue *q,
> return BLK_STS_NOTSUPP;
>
> /* The bio sector must point to the start of a sequential zone */
> - if (bio->bi_iter.bi_sector & (bdev_zone_sectors(bio->bi_bdev) - 1) ||
> + if (!bdev_is_zone_start(bio->bi_bdev, bio->bi_iter.bi_sector) ||
> !bio_zone_is_seq(bio))
> return BLK_STS_IOERR;
>
> diff --git a/block/blk-zoned.c b/block/blk-zoned.c
> index db829401d8d0..614b575be899 100644
> --- a/block/blk-zoned.c
> +++ b/block/blk-zoned.c
> @@ -277,10 +277,10 @@ int blkdev_zone_mgmt(struct block_device *bdev, enum req_op op,
> return -EINVAL;
>
> /* Check alignment (handle eventual smaller last zone) */
> - if (sector & (zone_sectors - 1))
> + if (!bdev_is_zone_start(bdev, sector))
> return -EINVAL;
>
> - if ((nr_sectors & (zone_sectors - 1)) && end_sector != capacity)
> + if (!bdev_is_zone_start(bdev, nr_sectors) && end_sector != capacity)
> return -EINVAL;
>
> /*
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index 0e40b014c40b..04b7cbfd7a2a 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -715,6 +715,7 @@ static inline unsigned int disk_zone_no(struct gendisk *disk, sector_t sector)
> {
> return 0;
> }
> +

whiteline change

> static inline unsigned int bdev_max_open_zones(struct block_device *bdev)
> {
> return 0;
> @@ -1304,6 +1305,23 @@ static inline sector_t bdev_zone_sectors(struct block_device *bdev)
> return q->limits.chunk_sectors;
> }
>
> +static inline sector_t bdev_offset_from_zone_start(struct block_device *bdev,
> + sector_t sec)
> +{
> + if (!bdev_is_zoned(bdev))

this helper should never be called outside of code supporting zones. So
why this check ?

> + return 0;
> +
> + return sec & (bdev_zone_sectors(bdev) - 1);
> +}
> +
> +static inline bool bdev_is_zone_start(struct block_device *bdev, sector_t sec)
> +{
> + if (!bdev_is_zoned(bdev))
> + return false;

Same here.

> +
> + return bdev_offset_from_zone_start(bdev, sec) == 0;
> +}
> +
> static inline int queue_dma_alignment(const struct request_queue *q)
> {
> return q ? q->limits.dma_alignment : 511;

--
Damien Le Moal
Western Digital Research