dma-buf: use the new iterator in dma_buf_debug_show

Simplifying the code a bit.
Signed-off-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005113742.1101-9-christian.koenig@amd.com

drivers/dma-buf/dma-buf.c

@@ -1356,10 +1356,9 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
 {
 	struct dma_buf *buf_obj;
 	struct dma_buf_attachment *attach_obj;
-	struct dma_resv *robj;
-	struct dma_resv_list *fobj;
+	struct dma_resv_iter cursor;
 	struct dma_fence *fence;
-	int count = 0, attach_count, shared_count, i;
+	int count = 0, attach_count;
 	size_t size = 0;
 	int ret;
 
@@ -1386,21 +1385,10 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
 				file_inode(buf_obj->file)->i_ino,
 				buf_obj->name ?: "");
 
-		robj = buf_obj->resv;
-		fence = dma_resv_excl_fence(robj);
-		if (fence)
-			seq_printf(s, "\tExclusive fence: %s %s %ssignalled\n",
-				   fence->ops->get_driver_name(fence),
-				   fence->ops->get_timeline_name(fence),
-				   dma_fence_is_signaled(fence) ? "" : "un");
-
-		fobj = rcu_dereference_protected(robj->fence,
-						 dma_resv_held(robj));
-		shared_count = fobj ? fobj->shared_count : 0;
-		for (i = 0; i < shared_count; i++) {
-			fence = rcu_dereference_protected(fobj->shared[i],
-							  dma_resv_held(robj));
-			seq_printf(s, "\tShared fence: %s %s %ssignalled\n",
+		dma_resv_for_each_fence(&cursor, buf_obj->resv, true, fence) {
+			seq_printf(s, "\t%s fence: %s %s %ssignalled\n",
+				   dma_resv_iter_is_exclusive(&cursor) ?
+					"Exclusive" : "Shared",
 				   fence->ops->get_driver_name(fence),
 				   fence->ops->get_timeline_name(fence),
 				   dma_fence_is_signaled(fence) ? "" : "un");