[Intel-gfx] [PATCH] drm/intel: fix up set_tiling for untiled->tiled transition

[Daniel Vetter]

Bug introduced in

commit 10ae9bd25acf394c8fa2f9d795dfa9cec4d19ed6
Author: Daniel Vetter <daniel.vetter at ffwll.ch>
Date:   Mon Feb 1 13:59:17 2010 +0100

    drm/i915: blow away userspace mappings before fence change

The problem is that when there's no fence reg assigned and the object
is mapped at a fenceable offset in the gtt, the userspace mappings won't
be teared down. Which happens on untiled->tiled transition quite often
on 4th gen and later because there fencing does not have any special
alignment constraints (as opposed to 2nd and 3rd gen on which I've tested
the original commit).

Bugzilla: http://bugs.freedesktop.org/show_bug.cgi?id=26993
Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
---
 drivers/gpu/drm/i915/i915_gem_tiling.c |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index b5c55d8..c01c878 100644
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -325,9 +325,12 @@ i915_gem_set_tiling(struct drm_device *dev, void *data,
 		 * need to ensure that any fence register is cleared.
 		 */
 		if (!i915_gem_object_fence_offset_ok(obj, args->tiling_mode))
-		    ret = i915_gem_object_unbind(obj);
+			ret = i915_gem_object_unbind(obj);
+		else if (obj_priv->fence_reg != I915_FENCE_REG_NONE)
+			ret = i915_gem_object_put_fence_reg(obj);
 		else
-		    ret = i915_gem_object_put_fence_reg(obj);
+			i915_gem_release_mmap(obj);
+
 		if (ret != 0) {
 			WARN(ret != -ERESTARTSYS,
 			     "failed to reset object for tiling switch");
-- 
1.7.0