Re: [PATCH v10 08/33] scsi: Use separate buf for START_STOP in sd_spinup_disk

[John Garry <john.g.garry@oracle.com>]

On 14/07/2023 22:33, Mike Christie wrote:
> We currently re-use the cmd buffer for the TUR and START_STOP commands
> which requires us to reset the buffer when retrying. This has us use
> separate buffers for the 2 commands so we can make them const and I think
> it makes it easier to handle for retries but does not add too much extra
> to the stack use.
> 
> Signed-off-by: Mike Christie <michael.christie@oracle.com>
> Reviewed-by: Christoph Hellwig <hch@lst.de>

Reviewed-by: John Garry <john.g.garry@oracle.com>

> ---
>   drivers/scsi/sd.c | 13 ++++++-------
>   1 file changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index 245419fe9358..f75e2d7a864c 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -2267,14 +2267,13 @@ sd_spinup_disk(struct scsi_disk *sdkp)
>   			 * Issue command to spin up drive when not ready
>   			 */
>   			if (!spintime) {
> +				/* Return immediately and start spin cycle */
> +				const u8 start_cmd[10] = { START_STOP, 1, 0, 0,
> +					sdkp->device->start_stop_pwr_cond ?
> +					0x11 : 1 };

same comment as previous patch

> +
>   				sd_printk(KERN_NOTICE, sdkp, "Spinning up disk...");
> -				cmd[0] = START_STOP;
> -				cmd[1] = 1;	/* Return immediately */
> -				memset((void *) &cmd[2], 0, 8);
> -				cmd[4] = 1;	/* Start spin cycle */
> -				if (sdkp->device->start_stop_pwr_cond)
> -					cmd[4] |= 1 << 4;
> -				scsi_execute_cmd(sdkp->device, cmd,
> +				scsi_execute_cmd(sdkp->device, start_cmd,
>   						 REQ_OP_DRV_IN, NULL, 0,
>   						 SD_TIMEOUT, sdkp->max_retries,
>   						 &exec_args);