[PATCH 2/5] DRM: Armada: Add Armada DRM driver

[Russell King - ARM Linux]

On Thu, Oct 10, 2013 at 06:23:26PM -0400, Rob Clark wrote:
> On Thu, Oct 10, 2013 at 5:59 PM, Russell King - ARM Linux
> <linux at arm.linux.org.uk> wrote:
> > On Thu, Oct 10, 2013 at 05:25:15PM -0400, Rob Clark wrote:
> >> probably this thread is applicable here too?
> >>
> >> https://lkml.org/lkml/2013/9/12/417
> >>
> >> (although.. we have at least a few  slightly differet variants on the
> >> same errno -> VM_FAULT_x switch in different drivers.. maybe we should
> >> do something better)
> >
> > Hmm.  It seems today's vm_insert_pfn() has the following error return
> > values:
> >
> > -EFAULT - virtual address outside vma
> > -EINVAL - track_pfn_insert() failure
> > -ENOMEM - failed to get locked pte
> > -EBUSY - entry already exists in pte
> >
> > So it seems my handling -EIO, -EAGAIN, -ERESTARTSYS and -EINTR are all
> > redundant and can be removed.  I'm not sure if it makes sense for this
> > to be generic - it looks like it's only Intel, gma500 and me who use
> > this, and Intel handles more error codes (due to it calling other
> > functions.)
> 
> I just noticed msm and omapdrm are missing the -EBUSY case (have some
> patches I need to send), which was why I mentioned this.  They do have
> other error cases from other fxns, so maybe something generic/common
> doesn't make sense..  but I realized i915 fixed the same issue a while
> back, so somewhere common has the advantage of somehow not forgetting
> to fix other drivers ;-)

Here's the promised delta:

 drivers/gpu/drm/armada/armada_gem.c |    5 -----
 1 files changed, 0 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/armada/armada_gem.c b/drivers/gpu/drm/armada/armada_gem.c
index 02de7a4..1e74f70 100644
--- a/drivers/gpu/drm/armada/armada_gem.c
+++ b/drivers/gpu/drm/armada/armada_gem.c
@@ -25,12 +25,7 @@ static int armada_gem_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 	ret = vm_insert_pfn(vma, addr, pfn);
 
 	switch (ret) {
-	case -EIO:
-	case -EAGAIN:
-		set_need_resched();
 	case 0:
-	case -ERESTARTSYS:
-	case -EINTR:
 	case -EBUSY:
 		return VM_FAULT_NOPAGE;
 	case -ENOMEM: