[PATCH v4 25/31] net/ena/base: modify customer metrics memory management

[<shaibran@amazon.com>]

From: Shai Brandes <shaibran@amazon.com>

1. Set buffer length to zero in case memory allocation failed
   and after memory is released.
2. The driver checks buffer_virt_addr for customer allocation
   success. In case the allocation fails, buffer_virt_addr
   may not necessarily be NULL.

Signed-off-by: Shai Brandes <shaibran@amazon.com>
Reviewed-by: Amit Bernstein <amitbern@amazon.com>
---
 drivers/net/ena/base/ena_com.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ena/base/ena_com.c b/drivers/net/ena/base/ena_com.c
index 2db21e7895..24756e5e76 100644
--- a/drivers/net/ena/base/ena_com.c
+++ b/drivers/net/ena/base/ena_com.c
@@ -3233,13 +3233,17 @@ int ena_com_allocate_customer_metrics_buffer(struct ena_com_dev *ena_dev)
 	struct ena_customer_metrics *customer_metrics = &ena_dev->customer_metrics;
 
 	customer_metrics->buffer_len = ENA_CUSTOMER_METRICS_BUFFER_SIZE;
+	customer_metrics->buffer_virt_addr = NULL;
+
 	ENA_MEM_ALLOC_COHERENT(ena_dev->dmadev,
 			       customer_metrics->buffer_len,
 			       customer_metrics->buffer_virt_addr,
 			       customer_metrics->buffer_dma_addr,
 			       customer_metrics->buffer_dma_handle);
-	if (unlikely(!customer_metrics->buffer_virt_addr))
+	if (unlikely(!customer_metrics->buffer_virt_addr)) {
+		customer_metrics->buffer_len = 0;
 		return ENA_COM_NO_MEM;
+	}
 
 	return 0;
 }
@@ -3283,6 +3287,7 @@ void ena_com_delete_customer_metrics_buffer(struct ena_com_dev *ena_dev)
 				      customer_metrics->buffer_dma_addr,
 				      customer_metrics->buffer_dma_handle);
 		customer_metrics->buffer_virt_addr = NULL;
+		customer_metrics->buffer_len = 0;
 	}
 }
 
-- 
2.17.1