[PATCH] drm/ttm: Fix swapin regression

[Thomas Hellstrom]

Commit "drm/ttm: Don't move non-existing data" didn't take the
swapped-out corner case into account. This patch corrects that.
Fixes blank screen after attempted suspend / hibernate on vmwgfx.

Signed-off-by: Thomas Hellstrom <thellstrom at vmware.com>
---
 drivers/gpu/drm/ttm/ttm_bo_util.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 15b86a9..4061521 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -353,7 +353,8 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo,
 	 * Don't move nonexistent data. Clear destination instead.
 	 */
 	if (old_iomap == NULL &&
-	    (ttm == NULL || ttm->state == tt_unpopulated)) {
+	    (ttm == NULL || (ttm->state == tt_unpopulated &&
+			     !(ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)))) {
 		memset_io(new_iomap, 0, new_mem->num_pages*PAGE_SIZE);
 		goto out2;
 	}
-- 
1.8.4.2