igc: Refactor igc_clean_rx_ring()

Refactor igc_clean_rx_ring() helper, preparing the code for AF_XDP
zero-copy support which is added by upcoming patches.

The refactor consists of encapsulating page-shared specific code into
its own helper, leaving common code that will be shared by both
page-shared and xsk pool in igc_clean_rx_ring().
Signed-off-by: Andre Guedes <andre.guedes@intel.com>
Signed-off-by: Vedang Patel <vedang.patel@intel.com>
Signed-off-by: Jithu Joseph <jithu.joseph@intel.com>
Reviewed-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Tested-by: Dvora Fuxbrumer <dvorax.fuxbrumer@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/igc/igc_main.c

@@ -346,11 +346,7 @@ static int igc_setup_all_tx_resources(struct igc_adapter *adapter)
 	return err;
 }
 
-/**
- * igc_clean_rx_ring - Free Rx Buffers per Queue
- * @rx_ring: ring to free buffers from
- */
-static void igc_clean_rx_ring(struct igc_ring *rx_ring)
+static void igc_clean_rx_ring_page_shared(struct igc_ring *rx_ring)
 {
 	u16 i = rx_ring->next_to_clean;
 
@@ -383,12 +379,21 @@ static void igc_clean_rx_ring(struct igc_ring *rx_ring)
 		if (i == rx_ring->count)
 			i = 0;
 	}
+}
+
+/**
+ * igc_clean_rx_ring - Free Rx Buffers per Queue
+ * @ring: ring to free buffers from
+ */
+static void igc_clean_rx_ring(struct igc_ring *ring)
+{
+	igc_clean_rx_ring_page_shared(ring);
 
-	clear_ring_uses_large_buffer(rx_ring);
+	clear_ring_uses_large_buffer(ring);
 
-	rx_ring->next_to_alloc = 0;
-	rx_ring->next_to_clean = 0;
-	rx_ring->next_to_use = 0;
+	ring->next_to_alloc = 0;
+	ring->next_to_clean = 0;
+	ring->next_to_use = 0;
 }
 
 /**