staging: android: ion: Clean unused debug_show memeber of the heap object

ION had supported heap debug info under /sys/kernel/debug/ion/<heap_name>.
This support have been removed but some leftovers (dead code) still exist.

This patch removes the existing dead code.

Fixes: 15c6098c ("staging: android: ion: Remove ion_handle and ion_client")
Signed-off-by: Alexey Skidanov <alexey.skidanov@intel.com>
Acked-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/android/ion/ion.h

@@ -157,8 +157,6 @@ struct ion_heap_ops {
  * @lock:		protects the free list
  * @waitqueue:		queue to wait on from deferred free thread
  * @task:		task struct of deferred free thread
- * @debug_show:		called when heap debug file is read to add any
- *			heap specific debug info to output
  *
  * Represents a pool of memory from which buffers can be made.  In some
  * systems the only heap is regular system memory allocated via vmalloc.
@@ -179,9 +177,6 @@ struct ion_heap {
 	spinlock_t free_lock;
 	wait_queue_head_t waitqueue;
 	struct task_struct *task;
-
-	int (*debug_show)(struct ion_heap *heap, struct seq_file *s,
-			  void *unused);
 };
 
 /**

drivers/staging/android/ion/ion_system_heap.c

@@ -212,29 +212,6 @@ static struct ion_heap_ops system_heap_ops = {
 	.shrink = ion_system_heap_shrink,
 };
 
-static int ion_system_heap_debug_show(struct ion_heap *heap, struct seq_file *s,
-				      void *unused)
-{
-	struct ion_system_heap *sys_heap = container_of(heap,
-							struct ion_system_heap,
-							heap);
-	int i;
-	struct ion_page_pool *pool;
-
-	for (i = 0; i < NUM_ORDERS; i++) {
-		pool = sys_heap->pools[i];
-
-		seq_printf(s, "%d order %u highmem pages %lu total\n",
-			   pool->high_count, pool->order,
-			   (PAGE_SIZE << pool->order) * pool->high_count);
-		seq_printf(s, "%d order %u lowmem pages %lu total\n",
-			   pool->low_count, pool->order,
-			   (PAGE_SIZE << pool->order) * pool->low_count);
-	}
-
-	return 0;
-}
-
 static void ion_system_heap_destroy_pools(struct ion_page_pool **pools)
 {
 	int i;
@@ -281,7 +258,6 @@ static struct ion_heap *__ion_system_heap_create(void)
 	if (ion_system_heap_create_pools(heap->pools))
 		goto free_heap;
 
-	heap->heap.debug_show = ion_system_heap_debug_show;
 	return &heap->heap;
 
 free_heap: