[Intel-gfx] [PATCH 2/2] drm/i915: refactor eb_get_batch()

[Chris Wilson]

On Wed, Jul 13, 2016 at 02:38:16PM +0200, Daniel Vetter wrote:
> On Thu, Jun 30, 2016 at 04:12:49PM +0100, Dave Gordon wrote:
> > Precursor for fix to secure batch execution. We will need to be able to
> > retrieve the batch VMA (as well as the batch itself) from the eb list,
> > so this patch extracts that part of eb_get_batch() into a separate
> > function, and moves both parts to a more logical place in the file, near
> > where the eb list is created.
> > 
> > Also, it may not be obvious, but the current execbuffer2 ioctl interface
> > requires that the buffer object containing the batch-to-be-executed be
> > the LAST entry in the exec2_list[] array (I expected it to be the first!).
> > 
> > To clarify this, we can replace the rather obscure construct
> > 	"list_entry(eb->vmas.prev, ...)"
> > in the old version of eb_get_batch() with the equivalent but more explicit
> > 	"list_last_entry(&eb->vmas,...)"
> > in the new eb_get_batch_vma() and of course add an explanatory comment.
> > 
> > Signed-off-by: Dave Gordon <david.s.gordon at intel.com>
> 
> I have no context on the secure batch fix you're talking about, but this
> here makes sense as an independent cleanup.

It won't help though, so this is just churn for no purpose.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre