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

[shaibran]

From: Shai Brandes <shaib...@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 <shaib...@amazon.com>
Reviewed-by: Amit Bernstein <amitb...@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