Merge commit '9f12600fe425bc28f0ccba034a77783c09c15af4' into for-linus

Backmerge of dcache.c changes from mainline.  It's that, or complete
rebase...

Conflicts:
	fs/splice.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 25 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.c b/drivers/gpu/drm/i915/i915_gem_gtt.c
index 62a5c3627b90..154b0f8bb88d 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.c
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.c
@@ -34,25 +34,35 @@ static void gen8_setup_private_ppat(struct drm_i915_private *dev_priv);
 
 bool intel_enable_ppgtt(struct drm_device *dev, bool full)
 {
-	if (i915.enable_ppgtt == 0 || !HAS_ALIASING_PPGTT(dev))
+	if (i915.enable_ppgtt == 0)
 		return false;
 
 	if (i915.enable_ppgtt == 1 && full)
 		return false;
 
+	return true;
+}
+
+static int sanitize_enable_ppgtt(struct drm_device *dev, int enable_ppgtt)
+{
+	if (enable_ppgtt == 0 || !HAS_ALIASING_PPGTT(dev))
+		return 0;
+
+	if (enable_ppgtt == 1)
+		return 1;
+
+	if (enable_ppgtt == 2 && HAS_PPGTT(dev))
+		return 2;
+
 #ifdef CONFIG_INTEL_IOMMU
 	/* Disable ppgtt on SNB if VT-d is on. */
 	if (INTEL_INFO(dev)->gen == 6 && intel_iommu_gfx_mapped) {
 		DRM_INFO("Disabling PPGTT because VT-d is on\n");
-		return false;
+		return 0;
 	}
 #endif
 
-	/* Full ppgtt disabled by default for now due to issues. */
-	if (full)
-		return HAS_PPGTT(dev) && (i915.enable_ppgtt == 2);
-	else
-		return HAS_ALIASING_PPGTT(dev);
+	return HAS_ALIASING_PPGTT(dev) ? 1 : 0;
 }
 
 #define GEN6_PPGTT_PD_ENTRIES 512
@@ -2031,6 +2041,14 @@ int i915_gem_gtt_init(struct drm_device *dev)
 		 gtt->base.total >> 20);
 	DRM_DEBUG_DRIVER("GMADR size = %ldM\n", gtt->mappable_end >> 20);
 	DRM_DEBUG_DRIVER("GTT stolen size = %zdM\n", gtt->stolen_size >> 20);
+	/*
+	 * i915.enable_ppgtt is read-only, so do an early pass to validate the
+	 * user's requested state against the hardware/driver capabilities.  We
+	 * do this now so that we can print out any log messages once rather
+	 * than every time we check intel_enable_ppgtt().
+	 */
+	i915.enable_ppgtt = sanitize_enable_ppgtt(dev, i915.enable_ppgtt);
+	DRM_DEBUG_DRIVER("ppgtt mode: %i\n", i915.enable_ppgtt);
 
 	return 0;
 }