[Intel-gfx] [PATCH v12 2/9] drm/i915: Use offsetof() to calculate the offset of members in PVINFO page

[Zhi Wang]

To get the offset of the members in PVINFO page, offsetof() looks much
better than the tricky approach in current code.

v7:

- Move "offsetof()" modification into a dedicated patch. (Joonas)

Suggested-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen at linux.intel.com>
Signed-off-by: Zhi Wang <zhi.a.wang at intel.com>
---
 drivers/gpu/drm/i915/i915_pvinfo.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_pvinfo.h b/drivers/gpu/drm/i915/i915_pvinfo.h
index 68bdf60..7b3cec4 100644
--- a/drivers/gpu/drm/i915/i915_pvinfo.h
+++ b/drivers/gpu/drm/i915/i915_pvinfo.h
@@ -104,7 +104,7 @@ struct vgt_if {
 } __packed;
 
 #define vgtif_reg(x) \
-	_MMIO((VGT_PVINFO_PAGE + (long)&((struct vgt_if *)NULL)->x))
+	_MMIO((VGT_PVINFO_PAGE + offsetof(struct vgt_if, x)))
 
 /* vGPU display status to be used by the host side */
 #define VGT_DRV_DISPLAY_NOT_READY 0
-- 
1.9.1