Re: [PATCH v2] sd: Consider max_xfer_blocks if opt_xfer_blocks is unusable

From: Martin K. Petersen
Date: Wed Mar 29 2017 - 22:37:51 EST


Fam Zheng <famz@xxxxxxxxxx> writes:

Fam,

> diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
> index fcfeddc..a5c7e67 100644
> --- a/drivers/scsi/sd.c
> +++ b/drivers/scsi/sd.c
> @@ -2957,6 +2957,7 @@ static int sd_revalidate_disk(struct gendisk *disk)
> rw_max = logical_to_sectors(sdp, sdkp->opt_xfer_blocks);
> } else
> rw_max = BLK_DEF_MAX_SECTORS;
> + rw_max = min_not_zero(rw_max, logical_to_sectors(sdp, dev_max));
>
> /* Combine with controller limits */
> q->limits.max_sectors = min(rw_max, queue_max_hw_sectors(q));

Instead of updating rw_max twice, how about:

} else
rw_max = min_not_zero(logical_to_sectors(sdp, dev_max),
BLK_DEF_MAX_SECTORS);

?

--
Martin K. Petersen Oracle Linux Engineering