~~~~~~~~~~~~~~~~~~~~~~~
Refer to the :ref:`Enqueue / Dequeue APIs <dmadev_enqueue_dequeue>` section of the dmadev library
-documentation for details on operation enqueue and submission API usage.
+documentation for details on operation enqueue, submission and completion API usage.
It is expected that, for efficiency reasons, a burst of operations will be enqueued to the
device via multiple enqueue calls between calls to the ``rte_dma_submit()`` function.
+
+When gathering completions, ``rte_dma_completed()`` should be used, up until the point an error
+occurs with an operation. If an error was encountered, ``rte_dma_completed_status()`` must be used
+to reset the device and continue processing operations. This function will also gather the status
+of each individual operation which is filled in to the ``status`` array provided as parameter
+by the application.
+
+The status codes supported by IOAT are:
+
+* ``RTE_DMA_STATUS_SUCCESSFUL``: The operation was successful.
+* ``RTE_DMA_STATUS_INVALID_SRC_ADDR``: The operation failed due to an invalid source address.
+* ``RTE_DMA_STATUS_INVALID_DST_ADDR``: The operation failed due to an invalid destination address.
+* ``RTE_DMA_STATUS_INVALID_LENGTH``: The operation failed due to an invalid descriptor length.
+* ``RTE_DMA_STATUS_DESCRIPTOR_READ_ERROR``: The device could not read the descriptor.
+* ``RTE_DMA_STATUS_ERROR_UNKNOWN``: The operation failed due to an unspecified error.
+
+The following code shows how to retrieve the number of successfully completed
+copies within a burst and then uses ``rte_dma_completed_status()`` to check
+which operation failed and reset the device to continue processing operations:
+
+.. code-block:: C
+
+ enum rte_dma_status_code status[COMP_BURST_SZ];
+ uint16_t count, idx, status_count;
+ bool error = 0;
+
+ count = rte_dma_completed(dev_id, vchan, COMP_BURST_SZ, &idx, &error);
+
+ if (error){
+ status_count = rte_dma_completed_status(dev_id, vchan, COMP_BURST_SZ, &idx, status);
+ }
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