[PATCH v3 2/2] staging: android: Remove BUG from ion_system_heap.c

[Tomer Samara <tomersamara98@gmail.com>]

Remove BUG()  at ion_sytem_heap.c and error handling to:
 - free_buffer_page
 - alloc_buffer_page
this fix the following checkpatch issue:
Avoid crashing the kernel - try using WARN_ON &
recovery code ratherthan BUG() or BUG_ON().

Signed-off-by: Tomer Samara <tomersamara98@gmail.com>
---
 drivers/staging/android/ion/ion_system_heap.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/android/ion/ion_system_heap.c b/drivers/staging/android/ion/ion_system_heap.c
index eac0632ab4e8..56d53268b82c 100644
--- a/drivers/staging/android/ion/ion_system_heap.c
+++ b/drivers/staging/android/ion/ion_system_heap.c
@@ -30,7 +30,7 @@ static int order_to_index(unsigned int order)
 	for (i = 0; i < NUM_ORDERS; i++)
 		if (order == orders[i])
 			return i;
-	BUG();
+
 	return -1;
 }
 
@@ -48,8 +48,13 @@ static struct page *alloc_buffer_page(struct ion_system_heap *heap,
 				      struct ion_buffer *buffer,
 				      unsigned long order)
 {
-	struct ion_page_pool *pool = heap->pools[order_to_index(order)];
+	struct ion_page_pool *pool;
+	int index = order_to_index(order);
 
+	if (index < 0)
+		return NULL;
+
+	pool = heap->pools[index];
 	return ion_page_pool_alloc(pool);
 }
 
@@ -58,6 +63,7 @@ static void free_buffer_page(struct ion_system_heap *heap,
 {
 	struct ion_page_pool *pool;
 	unsigned int order = compound_order(page);
+	int index;
 
 	/* go to system */
 	if (buffer->private_flags & ION_PRIV_FLAG_SHRINKER_FREE) {
@@ -65,8 +71,11 @@ static void free_buffer_page(struct ion_system_heap *heap,
 		return;
 	}
 
-	pool = heap->pools[order_to_index(order)];
+	index = order_to_index(order);
+	if (index < 0)
+		return;
 
+	pool = heap->pools[index];
 	ion_page_pool_free(pool, page);
 }
 
-- 
2.25.1