On Fri, Feb 03, 2017 at 09:54:50AM +0100, Hannes Reinecke wrote:
> From: Johannes Thumshirn <[email protected]>
>
> Check for a valid direction before starting the request, otherwise we risk
> running into an assertion in the scsi midlayer checking for vaild requests.
Good idea, but..
> +static bool sg_is_valid_direction(int dxfer_direction)
> +{
> + switch (dxfer_direction) {
> + case SG_DXFER_NONE:
> + case SG_DXFER_TO_DEV:
> + case SG_DXFER_FROM_DEV:
> + case SG_DXFER_TO_FROM_DEV:
This isn't strictly valid as sg doesn't actually handle real bidi
commands, but we work around it.
It might be a good idea to move the warning about it from sg_write
to here and use printk_ratelimited instead of the hand-rolled
per-thread warning there.
> + case SG_DXFER_UNKNOWN:
> + return true;
And how valid is this one (Question to Doug I guess): for a 0-sized
transfer we should be fine, but otherwise it should probably be
rejected.
