Re: [PATCH v3 5/5] target/file: enable WRITE SAME when protection info is enabled

[Sagi Grimberg <sagig@dev.mellanox.co.il>]

On 4/25/2015 5:33 PM, Akinobu Mita wrote:
> Now we can generate correct PI for WRITE SAME command, so it is
> unnecessary to disallow WRITE SAME when protection info is enabled.
>
> Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
> Cc: Nicholas Bellinger <nab@linux-iscsi.org>
> Cc: Sagi Grimberg <sagig@mellanox.com>
> Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
> Cc: Christoph Hellwig <hch@lst.de>
> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
> Cc: target-devel@vger.kernel.org
> Cc: linux-scsi@vger.kernel.org
> ---
> * No change from v2
>
>   drivers/target/target_core_file.c | 18 +++++++++++++-----
>   1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/target/target_core_file.c b/drivers/target/target_core_file.c
> index 829817a..fe98f58 100644
> --- a/drivers/target/target_core_file.c
> +++ b/drivers/target/target_core_file.c
> @@ -376,16 +376,12 @@ fd_execute_write_same(struct se_cmd *cmd)
>   	struct bio_vec *bvec;
>   	unsigned int len = 0, i;
>   	ssize_t ret;
> +	sense_reason_t rc;
>
>   	if (!nolb) {
>   		target_complete_cmd(cmd, SAM_STAT_GOOD);
>   		return 0;
>   	}
> -	if (cmd->prot_op) {
> -		pr_err("WRITE_SAME: Protection information with FILEIO"
> -		       " backends not supported\n");
> -		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
> -	}
>
>   	if (cmd->t_data_nents > 1 ||
>   	    cmd->t_data_sg[0].length != cmd->se_dev->dev_attrib.block_size) {
> @@ -397,6 +393,10 @@ fd_execute_write_same(struct se_cmd *cmd)
>   		return TCM_INVALID_CDB_FIELD;
>   	}
>
> +	rc = sbc_dif_verify(cmd, cmd->t_task_lba, nolb, 0, cmd->t_prot_sg, 0);
> +	if (rc)
> +		return rc;
> +
>   	bvec = kcalloc(nolb, sizeof(struct bio_vec), GFP_KERNEL);
>   	if (!bvec)
>   		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
> @@ -418,6 +418,14 @@ fd_execute_write_same(struct se_cmd *cmd)
>   		return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
>   	}
>
> +	if (cmd->prot_op) {
> +		ret = fd_do_rw(cmd, fd_dev->fd_prot_file, se_dev->prot_length,
> +				cmd->t_prot_sg, cmd->t_prot_nents,
> +				cmd->prot_length, 1);
> +		if (ret < 0)
> +			return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE;
> +	}
> +
>   	target_complete_cmd(cmd, SAM_STAT_GOOD);
>   	return 0;
>   }
>

This looks good,

iblock is needed too though. I think you just need a missing call to
iblock_alloc_bip() and you're good to go (you can use scsi_debug with
dif/dix to test it). I think it belongs in the same patch.

Sagi.