drm/i915: Downgrade *ERROR* message for invalid user input

When we detect that the user passed along an invalid handle or object,
we emit a warning as an aide for debugging. Since these are indeed only
for debugging user triggerable errors (and the errors are reported back
to userspace by the errno), the messages should only be at the debug
level and not claiming that there is a catastrophic error in the
driver/hardware.

References: https://bugs.freedesktop.org/show_bug.cgi?id=74704
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_gem.c

@@ -1619,7 +1619,7 @@ i915_gem_mmap_gtt(struct drm_file *file,
 	}
 
 	if (obj->madv != I915_MADV_WILLNEED) {
-		DRM_ERROR("Attempting to mmap a purgeable buffer\n");
+		DRM_DEBUG("Attempting to mmap a purgeable buffer\n");
 		ret = -EFAULT;
 		goto out;
 	}
@@ -1973,7 +1973,7 @@ i915_gem_object_get_pages(struct drm_i915_gem_object *obj)
 		return 0;
 
 	if (obj->madv != I915_MADV_WILLNEED) {
-		DRM_ERROR("Attempting to obtain a purgeable object\n");
+		DRM_DEBUG("Attempting to obtain a purgeable object\n");
 		return -EFAULT;
 	}
 
@@ -3234,7 +3234,7 @@ i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
 		alignment = map_and_fenceable ? fence_alignment :
 						unfenced_alignment;
 	if (map_and_fenceable && alignment & (fence_alignment - 1)) {
-		DRM_ERROR("Invalid object alignment requested %u\n", alignment);
+		DRM_DEBUG("Invalid object alignment requested %u\n", alignment);
 		return -EINVAL;
 	}
 
@@ -3244,7 +3244,7 @@ i915_gem_object_bind_to_vm(struct drm_i915_gem_object *obj,
 	 * before evicting everything in a vain attempt to find space.
 	 */
 	if (obj->base.size > gtt_max) {
-		DRM_ERROR("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%zu\n",
+		DRM_DEBUG("Attempting to bind an object larger than the aperture: object=%zd > %s aperture=%zu\n",
 			  obj->base.size,
 			  map_and_fenceable ? "mappable" : "total",
 			  gtt_max);
@@ -3917,13 +3917,13 @@ i915_gem_pin_ioctl(struct drm_device *dev, void *data,
 	}
 
 	if (obj->madv != I915_MADV_WILLNEED) {
-		DRM_ERROR("Attempting to pin a purgeable buffer\n");
+		DRM_DEBUG("Attempting to pin a purgeable buffer\n");
 		ret = -EFAULT;
 		goto out;
 	}
 
 	if (obj->pin_filp != NULL && obj->pin_filp != file) {
-		DRM_ERROR("Already pinned in i915_gem_pin_ioctl(): %d\n",
+		DRM_DEBUG("Already pinned in i915_gem_pin_ioctl(): %d\n",
 			  args->handle);
 		ret = -EINVAL;
 		goto out;
@@ -3970,7 +3970,7 @@ i915_gem_unpin_ioctl(struct drm_device *dev, void *data,
 	}
 
 	if (obj->pin_filp != file) {
-		DRM_ERROR("Not pinned by caller in i915_gem_pin_ioctl(): %d\n",
+		DRM_DEBUG("Not pinned by caller in i915_gem_pin_ioctl(): %d\n",
 			  args->handle);
 		ret = -EINVAL;
 		goto out;