From 74c1c694a2deab0561c1f502de9d32fdc7eb7b32 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 21 Sep 2017 12:01:35 +0100
Subject: [PATCH] drm/i915: Document the split in internal and public execbuf flags
Git-commit: 74c1c694a2deab0561c1f502de9d32fdc7eb7b32
Patch-mainline: v4.15-rc1
References: FATE#322643 bsc#1055900

Since we reuse the same field for the user passing in their control
flags, and for the kernel to track a couple of bits of state, document
and check that those do not overlap.

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170921110135.15990-1-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -58,6 +58,7 @@ enum {
 
 #define __EXEC_HAS_RELOC	BIT(31)
 #define __EXEC_VALIDATED	BIT(30)
+#define __EXEC_INTERNAL_FLAGS	(~0u << 30)
 #define UPDATE			PIN_OFFSET_FIXED
 
 #define BATCH_OFFSET_BIAS (256*1024)
@@ -2197,6 +2198,7 @@ i915_gem_do_execbuffer(struct drm_device
 	int out_fence_fd = -1;
 	int err;
 
+	BUILD_BUG_ON(__EXEC_INTERNAL_FLAGS & ~__I915_EXEC_ILLEGAL_FLAGS);
 	BUILD_BUG_ON(__EXEC_OBJECT_INTERNAL_FLAGS &
 		     ~__EXEC_OBJECT_UNKNOWN_FLAGS);