From 51f9468f13bc7fd1a67a1e7c75ac3dca5ac20441 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Wed, 11 Dec 2019 11:04:35 +0000
Subject: drm/i915: Simplify error escape from cmdparser
Git-commit: 37d1151ce75ea2a9ca7274cb0c93f21db9ab431a
Patch-mainline: v5.6-rc1
References: jsc#SLE-12680, jsc#SLE-12880, jsc#SLE-12882, jsc#SLE-12883, jsc#SLE-13496, jsc#SLE-15322

We need to flush the destination buffer, even on error, to maintain
consistent cache state. Thereby removing the jump on error past the
clear, and reducing the loop-escape mechanism to a mere break.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191211110437.4082687-3-chris@chris-wilson.co.uk
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/i915/i915_cmd_parser.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c
index 2f5811d3707e..b692c40348a1 100644
--- a/drivers/gpu/drm/i915/i915_cmd_parser.c
+++ b/drivers/gpu/drm/i915/i915_cmd_parser.c
@@ -1453,7 +1453,7 @@ int intel_engine_cmd_parser(struct intel_engine_cs *engine,
 		if (!desc) {
 			DRM_DEBUG("CMD: Unrecognized command: 0x%08X\n", *cmd);
 			ret = -EINVAL;
-			goto err;
+			break;
 		}
 
 		if (desc->flags & CMD_DESC_FIXED)
@@ -1467,21 +1467,18 @@ int intel_engine_cmd_parser(struct intel_engine_cs *engine,
 				  length,
 				  batch_end - cmd);
 			ret = -EINVAL;
-			goto err;
+			break;
 		}
 
 		if (!check_cmd(engine, desc, cmd, length)) {
 			ret = -EACCES;
-			goto err;
+			break;
 		}
 
 		if (desc->cmd.value == MI_BATCH_BUFFER_START) {
 			ret = check_bbstart(cmd, offset, length, batch_length,
 					    batch_addr, shadow_addr,
 					    jump_whitelist);
-
-			if (ret)
-				goto err;
 			break;
 		}
 
@@ -1493,7 +1490,7 @@ int intel_engine_cmd_parser(struct intel_engine_cs *engine,
 		if  (cmd >= batch_end) {
 			DRM_DEBUG("CMD: Got to the end of the buffer w/o a BBE cmd!\n");
 			ret = -EINVAL;
-			goto err;
+			break;
 		}
 	} while (1);
 
@@ -1503,7 +1500,6 @@ int intel_engine_cmd_parser(struct intel_engine_cs *engine,
 		drm_clflush_virt_range(ptr, (void *)(cmd + 1) - ptr);
 	}
 
-err:
 	if (!IS_ERR_OR_NULL(jump_whitelist))
 		kfree(jump_whitelist);
 	i915_gem_object_unpin_map(shadow->obj);
-- 
2.28.0