[PATCH v3 net 4/4] ixgbevf: Fix passing 0 to ERR_PTR in ixgbevf_run_xdp()

[Yue Haibing]

ixgbevf_run_xdp() converts customed xdp action to a negative error code
with the sk_buff pointer type which be checked with IS_ERR in
ixgbevf_clean_rx_irq(). Remove this error pointer handing instead use
plain int return value.

Fixes: c7aec59657b6 ("ixgbevf: Add XDP support for pass and drop actions")
Reviewed-by: Jacob Keller <jacob.e.keller@xxxxxxxxx>
Signed-off-by: Yue Haibing <yuehaibing@xxxxxxxxxx>
---
 .../net/ethernet/intel/ixgbevf/ixgbevf_main.c | 23 ++++++++-----------
 1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
index 149911e3002a..183d2305d058 100644
--- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
+++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c
@@ -732,10 +732,6 @@ static bool ixgbevf_cleanup_headers(struct ixgbevf_ring *rx_ring,
 				    union ixgbe_adv_rx_desc *rx_desc,
 				    struct sk_buff *skb)
 {
-	/* XDP packets use error pointer so abort at this point */
-	if (IS_ERR(skb))
-		return true;
-
 	/* verify that the packet does not have any known errors */
 	if (unlikely(ixgbevf_test_staterr(rx_desc,
 					  IXGBE_RXDADV_ERR_FRAME_ERR_MASK))) {
@@ -1044,9 +1040,9 @@ static int ixgbevf_xmit_xdp_ring(struct ixgbevf_ring *ring,
 	return IXGBEVF_XDP_TX;
 }
 
-static struct sk_buff *ixgbevf_run_xdp(struct ixgbevf_adapter *adapter,
-				       struct ixgbevf_ring  *rx_ring,
-				       struct xdp_buff *xdp)
+static int ixgbevf_run_xdp(struct ixgbevf_adapter *adapter,
+			   struct ixgbevf_ring *rx_ring,
+			   struct xdp_buff *xdp)
 {
 	int result = IXGBEVF_XDP_PASS;
 	struct ixgbevf_ring *xdp_ring;
@@ -1080,7 +1076,7 @@ static struct sk_buff *ixgbevf_run_xdp(struct ixgbevf_adapter *adapter,
 		break;
 	}
 xdp_out:
-	return ERR_PTR(-result);
+	return result;
 }
 
 static unsigned int ixgbevf_rx_frame_truesize(struct ixgbevf_ring *rx_ring,
@@ -1122,6 +1118,7 @@ static int ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
 	struct sk_buff *skb = rx_ring->skb;
 	bool xdp_xmit = false;
 	struct xdp_buff xdp;
+	int xdp_res = 0;
 
 	/* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
 #if (PAGE_SIZE < 8192)
@@ -1165,11 +1162,11 @@ static int ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
 			/* At larger PAGE_SIZE, frame_sz depend on len size */
 			xdp.frame_sz = ixgbevf_rx_frame_truesize(rx_ring, size);
 #endif
-			skb = ixgbevf_run_xdp(adapter, rx_ring, &xdp);
+			xdp_res = ixgbevf_run_xdp(adapter, rx_ring, &xdp);
 		}
 
-		if (IS_ERR(skb)) {
-			if (PTR_ERR(skb) == -IXGBEVF_XDP_TX) {
+		if (xdp_res) {
+			if (xdp_res == IXGBEVF_XDP_TX) {
 				xdp_xmit = true;
 				ixgbevf_rx_buffer_flip(rx_ring, rx_buffer,
 						       size);
@@ -1189,7 +1186,7 @@ static int ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
 		}
 
 		/* exit if we failed to retrieve a buffer */
-		if (!skb) {
+		if (!xdp_res && !skb) {
 			rx_ring->rx_stats.alloc_rx_buff_failed++;
 			rx_buffer->pagecnt_bias++;
 			break;
@@ -1203,7 +1200,7 @@ static int ixgbevf_clean_rx_irq(struct ixgbevf_q_vector *q_vector,
 			continue;
 
 		/* verify the packet layout is correct */
-		if (ixgbevf_cleanup_headers(rx_ring, rx_desc, skb)) {
+		if (xdp_res || ixgbevf_cleanup_headers(rx_ring, rx_desc, skb)) {
 			skb = NULL;
 			continue;
 		}
-- 
2.34.1