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

[Tomer Samara]

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 <tomersamar...@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