From 29326a167adbdafd8150e7a48657fb1e469f96bd Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 23 Aug 2019 16:39:44 +0100
Subject: drm/i915: Flush the existing fence before GGTT read/write
Git-commit: 29326a167adbdafd8150e7a48657fb1e469f96bd
Patch-mainline: v5.4-rc1
References: bsc#1152489

Our fence management is lazy, very lazy. If the user marks an object as
untiled, we do not immediately flush the fence but merely mark it as
dirty. On the next use we have to remember to check and remove the fence,
by which time we hope it is idle and we do not have to wait.

v2: Throw away the old fence on the next ggtt_pin.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111468
Fixes: 1f7fd484fff1 ("drm/i915: Replace i915_vma_put_fence()")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Matthew Auld <matthew.auld@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823153944.20630-1-chris@chris-wilson.co.uk
(cherry picked from commit 636e83f2f208555c3d19d8b454ebdd8d8f4652cc)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
---
 drivers/gpu/drm/i915/i915_gem.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index ec9a46c276de..95e7c52cf8ed 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -1027,6 +1027,14 @@ i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj,
 			return ERR_PTR(ret);
 	}
 
+	if (vma->fence && !i915_gem_object_is_tiled(obj)) {
+		mutex_lock(&vma->vm->mutex);
+		ret = i915_vma_revoke_fence(vma);
+		mutex_unlock(&vma->vm->mutex);
+		if (ret)
+			return ERR_PTR(ret);
+	}
+
 	ret = i915_vma_pin(vma, size, alignment, flags | PIN_GLOBAL);
 	if (ret)
 		return ERR_PTR(ret);
-- 
2.28.0