Re: [PATCH block v2 1/3] block: Add @flags argument to bdev_write_zeroes_sectors()

[Bob Liu]

On 1/16/20 8:35 PM, Kirill Tkhai wrote:
> This is a preparation for next patch, which introduces
> a new flag BLKDEV_ZERO_ALLOCATE for calls, which need
> only allocation of blocks and don't need actual blocks
> zeroing.
> 
> CC: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
> Signed-off-by: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
> ---
>  block/blk-lib.c                     |    6 +++---
>  drivers/md/dm-kcopyd.c              |    2 +-
>  drivers/target/target_core_iblock.c |    4 ++--
>  include/linux/blkdev.h              |    3 ++-
>  4 files changed, 8 insertions(+), 7 deletions(-)
> 

Looks good to me.
Reviewed-by: Bob Liu <bob.liu@xxxxxxxxxx>

> diff --git a/block/blk-lib.c b/block/blk-lib.c
> index 5f2c429d4378..3e38c93cfc53 100644
> --- a/block/blk-lib.c
> +++ b/block/blk-lib.c
> @@ -224,7 +224,7 @@ static int __blkdev_issue_write_zeroes(struct block_device *bdev,
>  		return -EPERM;
>  
>  	/* Ensure that max_write_zeroes_sectors doesn't overflow bi_size */
> -	max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev);
> +	max_write_zeroes_sectors = bdev_write_zeroes_sectors(bdev, 0);
>  
>  	if (max_write_zeroes_sectors == 0)
>  		return -EOPNOTSUPP;
> @@ -362,7 +362,7 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
>  	sector_t bs_mask;
>  	struct bio *bio;
>  	struct blk_plug plug;
> -	bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev);
> +	bool try_write_zeroes = !!bdev_write_zeroes_sectors(bdev, 0);
>  
>  	bs_mask = (bdev_logical_block_size(bdev) >> 9) - 1;
>  	if ((sector | nr_sects) & bs_mask)
> @@ -391,7 +391,7 @@ int blkdev_issue_zeroout(struct block_device *bdev, sector_t sector,
>  			try_write_zeroes = false;
>  			goto retry;
>  		}
> -		if (!bdev_write_zeroes_sectors(bdev)) {
> +		if (!bdev_write_zeroes_sectors(bdev, 0)) {
>  			/*
>  			 * Zeroing offload support was indicated, but the
>  			 * device reported ILLEGAL REQUEST (for some devices
> diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
> index 1bbe4a34ef4c..f1b8e7926dd4 100644
> --- a/drivers/md/dm-kcopyd.c
> +++ b/drivers/md/dm-kcopyd.c
> @@ -831,7 +831,7 @@ void dm_kcopyd_copy(struct dm_kcopyd_client *kc, struct dm_io_region *from,
>  		 */
>  		job->rw = REQ_OP_WRITE_ZEROES;
>  		for (i = 0; i < job->num_dests; i++)
> -			if (!bdev_write_zeroes_sectors(job->dests[i].bdev)) {
> +			if (!bdev_write_zeroes_sectors(job->dests[i].bdev, 0)) {
>  				job->rw = WRITE;
>  				break;
>  			}
> diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
> index 51ffd5c002de..73a63e197bf5 100644
> --- a/drivers/target/target_core_iblock.c
> +++ b/drivers/target/target_core_iblock.c
> @@ -117,7 +117,7 @@ static int iblock_configure_device(struct se_device *dev)
>  	 * Enable write same emulation for IBLOCK and use 0xFFFF as
>  	 * the smaller WRITE_SAME(10) only has a two-byte block count.
>  	 */
> -	max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd);
> +	max_write_zeroes_sectors = bdev_write_zeroes_sectors(bd, 0);
>  	if (max_write_zeroes_sectors)
>  		dev->dev_attrib.max_write_same_len = max_write_zeroes_sectors;
>  	else
> @@ -468,7 +468,7 @@ iblock_execute_write_same(struct se_cmd *cmd)
>  		return TCM_INVALID_CDB_FIELD;
>  	}
>  
> -	if (bdev_write_zeroes_sectors(bdev)) {
> +	if (bdev_write_zeroes_sectors(bdev, 0)) {
>  		if (!iblock_execute_zero_out(bdev, cmd))
>  			return 0;
>  	}
> diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
> index c45779f00cbd..4cd69552df9a 100644
> --- a/include/linux/blkdev.h
> +++ b/include/linux/blkdev.h
> @@ -1418,7 +1418,8 @@ static inline unsigned int bdev_write_same(struct block_device *bdev)
>  	return 0;
>  }
>  
> -static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev)
> +static inline unsigned int bdev_write_zeroes_sectors(struct block_device *bdev,
> +						     unsigned int flags)
>  {
>  	struct request_queue *q = bdev_get_queue(bdev);
>  
> 
>