RE: [PATCH v6 1/5] scsi: Adjust DBD setting in mode sense for caching mode page per LLD

[Avri Altman <Avri.Altman@wdc.com>]

> 
> UFS JEDEC standards require DBD field to be set to 1 in mode sense command.
> This patch allows LLD to define the setting of DBD if required.
> 
> Signed-off-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Avri Altman <avri.altman@wdc.com>

> ---
>  drivers/scsi/scsi_lib.c    | 2 ++
>  include/scsi/scsi_device.h | 1 +
>  2 files changed, 3 insertions(+)
> 
> diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index
> 5447738..3812e90 100644
> --- a/drivers/scsi/scsi_lib.c
> +++ b/drivers/scsi/scsi_lib.c
> @@ -2108,6 +2108,8 @@ void scsi_exit_queue(void)
> 
>         memset(data, 0, sizeof(*data));
>         memset(&cmd[0], 0, 12);
> +
> +       dbd = sdev->set_dbd_for_ms ? 8 : dbd;
>         cmd[1] = dbd & 0x18;    /* allows DBD and LLBA bits */
>         cmd[2] = modepage;
> 
> diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index
> 3ed836d..f8312a3 100644
> --- a/include/scsi/scsi_device.h
> +++ b/include/scsi/scsi_device.h
> @@ -172,6 +172,7 @@ struct scsi_device {
>                                      * because we did a bus reset. */
>         unsigned use_10_for_rw:1; /* first try 10-byte read / write */
>         unsigned use_10_for_ms:1; /* first try 10-byte mode sense/select */
> +       unsigned set_dbd_for_ms:1; /* Set "DBD" field in mode sense */
>         unsigned no_report_opcodes:1;   /* no REPORT SUPPORTED OPERATION
> CODES */
>         unsigned no_write_same:1;       /* no WRITE SAME command */
>         unsigned use_16_for_rw:1; /* Use read/write(16) over read/write(10) */
> --
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