On 2024/02/29 9:23, Bart Van Assche wrote:
> READ(10) and WRITE(10) are sufficient for zoned UFS devices. UFS device
> manufacturers prefer to minimize the size of their firmware and hence
> also the number of SCSI commands that are supported. Hence this patch
> that switches from READ(16)/WRITE(16)/SYNCHRONIZE CACHE(16) to READ(10)/
> WRITE(10)/SYNCHRONIZE CACHE(10) for zoned UFS devices. The 16-byte
> commands are still used for zoned devices with more than 2**32 logical
> blocks because of the following code in sd_read_capacity():
>
> if (sdkp->capacity > 0xffffffff)
> sdp->use_16_for_rw = 1;
>
> Cc: Damien Le Moal <dlemoal@xxxxxxxxxx>
> Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
> ---
> drivers/ata/libata-scsi.c | 10 ++++++++--
> drivers/scsi/sd_zbc.c | 5 -----
> 2 files changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
> index 0a0f483124c3..a196dce4bbc3 100644
> --- a/drivers/ata/libata-scsi.c
> +++ b/drivers/ata/libata-scsi.c
> @@ -986,8 +986,14 @@ static void ata_gen_ata_sense(struct ata_queued_cmd *qc)
>
> void ata_scsi_sdev_config(struct scsi_device *sdev)
> {
> - sdev->use_10_for_rw = 1;
> - sdev->use_10_for_ms = 1;
> + if (sdev->type == TYPE_ZBC) {
> + /* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
> + sdev->use_16_for_rw = 1;
> + sdev->use_16_for_sync = 1;
scsi_add_lun() sets use_10_for_rw to "1" so can we clear it to "0" here again
like was done in the sd_zbc.c hunk below that you removed ?
> + } else {
> + sdev->use_10_for_rw = 1;
> + sdev->use_10_for_ms = 1;
> + }
> sdev->no_write_same = 1;
>
> /* Schedule policy is determined by ->qc_defer() callback and
> diff --git a/drivers/scsi/sd_zbc.c b/drivers/scsi/sd_zbc.c
> index 26af5ab7d7c1..bcdb21706d3f 100644
> --- a/drivers/scsi/sd_zbc.c
> +++ b/drivers/scsi/sd_zbc.c
> @@ -924,11 +924,6 @@ int sd_zbc_read_zones(struct scsi_disk *sdkp, u8 buf[SD_BUF_SIZE])
> return 0;
> }
>
> - /* READ16/WRITE16/SYNC16 is mandatory for ZBC devices */
> - sdkp->device->use_16_for_rw = 1;
> - sdkp->device->use_10_for_rw = 0;
> - sdkp->device->use_16_for_sync = 1;
> -
> /* Check zoned block device characteristics (unconstrained reads) */
> ret = sd_zbc_check_zoned_characteristics(sdkp, buf);
> if (ret)
--
Damien Le Moal
Western Digital Research
