net: aquantia: invalid checksumm offload implementation

Packets with marked invalid IP/UDP/TCP checksums were considered as good
by the driver. The error was in a logic, processing offload bits in
RX descriptor.

Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: Dmitry Bogdanov <dmitry.bogdanov@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 41 insertions, 30 deletions

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index 3db91446cc67..74550ccc7a20 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -172,6 +172,27 @@ bool aq_ring_tx_clean(struct aq_ring_s *self)
         return !!budget;
 }
 
+static void aq_rx_checksum(struct aq_ring_s *self,
+                           struct aq_ring_buff_s *buff,
+                           struct sk_buff *skb)
+{
+        if (!(self->aq_nic->ndev->features & NETIF_F_RXCSUM))
+                return;
+
+        if (unlikely(buff->is_cso_err)) {
+                ++self->stats.rx.errors;
+                skb->ip_summed = CHECKSUM_NONE;
+                return;
+        }
+        if (buff->is_ip_cso) {
+                __skb_incr_checksum_unnecessary(skb);
+                if (buff->is_udp_cso || buff->is_tcp_cso)
+                        __skb_incr_checksum_unnecessary(skb);
+        } else {
+                skb->ip_summed = CHECKSUM_NONE;
+        }
+}
+
 #define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
 int aq_ring_rx_clean(struct aq_ring_s *self,
                      struct napi_struct *napi,
@@ -267,18 +288,8 @@ int aq_ring_rx_clean(struct aq_ring_s *self,
                 }
 
                 skb->protocol = eth_type_trans(skb, ndev);
-                if (unlikely(buff->is_cso_err)) {
-                        ++self->stats.rx.errors;
-                        skb->ip_summed = CHECKSUM_NONE;
-                } else {
-                        if (buff->is_ip_cso) {
-                                __skb_incr_checksum_unnecessary(skb);
-                                if (buff->is_udp_cso || buff->is_tcp_cso)
-                                        __skb_incr_checksum_unnecessary(skb);
-                        } else {
-                                skb->ip_summed = CHECKSUM_NONE;
-                        }
-                }
+
+                aq_rx_checksum(self, buff, skb);
 
                 skb_set_hash(skb, buff->rss_hash,
                              buff->is_hash_l4 ? PKT_HASH_TYPE_L4 :
diff --git a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
index 3aec56623bf5..179ce12fe4d8 100644
--- a/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
+++ b/drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_b0.c
@@ -660,9 +660,9 @@ static int hw_atl_b0_hw_ring_rx_receive(struct aq_hw_s *self,
                 struct hw_atl_rxd_wb_s *rxd_wb = (struct hw_atl_rxd_wb_s *)
                         &ring->dx_ring[ring->hw_head * HW_ATL_B0_RXD_SIZE];
 
-                unsigned int is_err = 1U;
                 unsigned int is_rx_check_sum_enabled = 0U;
                 unsigned int pkt_type = 0U;
+                u8 rx_stat = 0U;
 
                 if (!(rxd_wb->status & 0x1U)) { /* RxD is not done */
                         break;
@@ -670,35 +670,35 @@ static int hw_atl_b0_hw_ring_rx_receive(struct aq_hw_s *self,
 
                 buff = &ring->buff_ring[ring->hw_head];
 
-                is_err = (0x0000003CU & rxd_wb->status);
+                rx_stat = (0x0000003CU & rxd_wb->status) >> 2;
 
                 is_rx_check_sum_enabled = (rxd_wb->type) & (0x3U << 19);
-                is_err &= ~0x20U; /* exclude validity bit */
 
                 pkt_type = 0xFFU & (rxd_wb->type >> 4);
 
-                if (is_rx_check_sum_enabled) {
-                        if (0x0U == (pkt_type & 0x3U))
-                                buff->is_ip_cso = (is_err & 0x08U) ? 0U : 1U;
+                if (is_rx_check_sum_enabled & BIT(0) &&
+                    (0x0U == (pkt_type & 0x3U)))
+                        buff->is_ip_cso = (rx_stat & BIT(1)) ? 0U : 1U;
 
+                if (is_rx_check_sum_enabled & BIT(1)) {
                         if (0x4U == (pkt_type & 0x1CU))
-                                buff->is_udp_cso = buff->is_cso_err ? 0U : 1U;
+                                buff->is_udp_cso = (rx_stat & BIT(2)) ? 0U :
+                                                   !!(rx_stat & BIT(3));
                         else if (0x0U == (pkt_type & 0x1CU))
-                                buff->is_tcp_cso = buff->is_cso_err ? 0U : 1U;
-
-                        /* Checksum offload workaround for small packets */
-                        if (rxd_wb->pkt_len <= 60) {
-                                buff->is_ip_cso = 0U;
-                                buff->is_cso_err = 0U;
-                        }
+                                buff->is_tcp_cso = (rx_stat & BIT(2)) ? 0U :
+                                                   !!(rx_stat & BIT(3));
+                }
+                buff->is_cso_err = !!(rx_stat & 0x6);
+                /* Checksum offload workaround for small packets */
+                if (unlikely(rxd_wb->pkt_len <= 60)) {
+                        buff->is_ip_cso = 0U;
+                        buff->is_cso_err = 0U;
                 }
-
-                is_err &= ~0x18U;
 
                 dma_unmap_page(ndev, buff->pa, buff->len, DMA_FROM_DEVICE);
 
-                if (is_err || rxd_wb->type & 0x1000U) {
-                        /* status error or DMA error */
+                if ((rx_stat & BIT(0)) || rxd_wb->type & 0x1000U) {
+                        /* MAC error or DMA error */
                         buff->is_error = 1U;
                 } else {
                         if (self->aq_nic_cfg->is_rss) {