On Mon, Jan 21, 2019 at 11:17:31AM +0000, Avri Altman wrote: > > > > On Thu, Jan 10, 2019 at 05:53:03PM +0200, Avri Altman wrote: > > > Allow to read descriptors via raw upiu. This in fact was forbidden just > > > as a precaution, as ufs-bsg actually enforces which functionality is > > > supported. > > > > This still looks rather odd. Why is this using a buffer after the > > bsg_request? Nornally you'd directly pass down the pages that bsg > > locked down to the low-level driver to work on. > Right. All this is done in ufs-bsg as ufshcd has no concept of bsg job - > See the next patch. Well, I still don't understand what you are actually doing in this patch then. The second and third hunks are pretty obvious, they remove the previous restriction on UPIU_QUERY_OPCODE_WRITE_DESC with a non-NULL buffer, and seem to vaguely match the patch description. The first hunk on the other hand adds new code for the UPIU_QUERY_OPCODE_READ_DESC case which copies data to the passed in buffer from the hardware, that goes into the ->reply field of the bsg buffer, which basically is the scsi sense buffer, that is out of line return information. But why are we returning information in the out of line reply buffer, and not the in-line data buffer? Maybe there is a good explanation for that, but it clear is not documented in the commit log. > > Thanks, > Avri ---end quoted text---
