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

[Kirill Tkhai]

On 19.01.2020 04:46, Bob Liu wrote:
> 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>

Thanks, Bob.
 
>> 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);
>>  
>>
>>
>