Re: [PATCH 1/4] target: Add target_submit_cmd_map_mem for SGL fabric memory passthrough

["Nicholas A. Bellinger" <nab@linux-iscsi.org>]

On Tue, 2012-10-02 at 11:17 -0400, Christoph Hellwig wrote:
> On Tue, Oct 02, 2012 at 07:15:44AM +0000, Nicholas A. Bellinger wrote:
> > From: Nicholas Bellinger <nab@linux-iscsi.org>
> > 
> > This patch adds a new TARGET_SCF_MAP_MEM flag within __target_submit_cmd()
> > + a target_submit_cmd_map_mem() wrapper to pass pre-allocated SGL memory
> > using existing transport_generic_map_mem_to_cmd() logic into the generic
> > target submit I/O codepath.
> 
> Instead of requiring a flag we could simply check for the sglist_count
> to be non-zero instead of requiring multiple pieces of information to
> be in sync.
> 

Mmmm, fair point here.  In that case I'd rather rename
__target_submit_cmd() to target_submit_cmd_mapsgl(), and update the
target_submit_cmd() wrapper accordingly.

> I'd also be tempted to remove the wrappers and just expose what is
> __target_submit_cmd now to the drivers, but that can be done
> independently as a cleanup.
> 

<nod>, dropping the extra target_submit_cmd_map_mem bit + flag now.

Thanks hch!

--nab