s390/qeth: simplify qeth_receive_skb()

Now that the OSN code is gone, we don't need the second switch statement
in the RX path. And getting rid of its (unreachable) default case is a
nice simplification.

Also don't pass in the full HW header, all we still need is a flag to
indicate whether the skb can use CSO. This we can already obtain during
the first peek at the HW header.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Alexandra Winter <wintera@linux.ibm.com>
Reviewed-by: Wenjia Zhang <wenjia@linux.ibm.com>
Signed-off-by: Alexandra Winter <wintera@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index d32aa8b..629a7f5 100644 (file)
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -5575,29 +5575,9 @@ static void qeth_l3_rebuild_skb(struct qeth_card *card, struct sk_buff *skb,
 #endif
 
 static void qeth_receive_skb(struct qeth_card *card, struct sk_buff *skb,
-                            struct qeth_hdr *hdr, bool uses_frags)
+                            bool uses_frags, bool is_cso)
 {
        struct napi_struct *napi = &card->napi;
-       bool is_cso;
-
-       switch (hdr->hdr.l2.id) {
-#if IS_ENABLED(CONFIG_QETH_L3)
-       case QETH_HEADER_TYPE_LAYER3:
-               qeth_l3_rebuild_skb(card, skb, hdr);
-               is_cso = hdr->hdr.l3.ext_flags & QETH_HDR_EXT_CSUM_TRANSP_REQ;
-               break;
-#endif
-       case QETH_HEADER_TYPE_LAYER2:
-               is_cso = hdr->hdr.l2.flags[1] & QETH_HDR_EXT_CSUM_TRANSP_REQ;
-               break;
-       default:
-               /* never happens */
-               if (uses_frags)
-                       napi_free_frags(napi);
-               else
-                       kfree_skb(skb);
-               return;
-       }
 
        if (is_cso && (card->dev->features & NETIF_F_RXCSUM)) {
                skb->ip_summed = CHECKSUM_UNNECESSARY;
@@ -5654,6 +5634,7 @@ static int qeth_extract_skb(struct qeth_card *card,
        struct qeth_hdr *hdr;
        struct sk_buff *skb;
        int skb_len = 0;
+       bool is_cso;
 
        element = &buffer->element[*element_no];
 
@@ -5673,11 +5654,15 @@ next_packet:
        switch (hdr->hdr.l2.id) {
        case QETH_HEADER_TYPE_LAYER2:
                skb_len = hdr->hdr.l2.pkt_length;
+               is_cso = hdr->hdr.l2.flags[1] & QETH_HDR_EXT_CSUM_TRANSP_REQ;
+
                linear_len = ETH_HLEN;
                headroom = 0;
                break;
        case QETH_HEADER_TYPE_LAYER3:
                skb_len = hdr->hdr.l3.length;
+               is_cso = hdr->hdr.l3.ext_flags & QETH_HDR_EXT_CSUM_TRANSP_REQ;
+
                if (!IS_LAYER3(card)) {
                        QETH_CARD_STAT_INC(card, rx_dropped_notsupp);
                        goto walk_packet;
@@ -5804,7 +5789,12 @@ walk_packet:
        *element_no = element - &buffer->element[0];
        *__offset = offset;
 
-       qeth_receive_skb(card, skb, hdr, uses_frags);
+#if IS_ENABLED(CONFIG_QETH_L3)
+       if (hdr->hdr.l2.id == QETH_HEADER_TYPE_LAYER3)
+               qeth_l3_rebuild_skb(card, skb, hdr);
+#endif
+
+       qeth_receive_skb(card, skb, uses_frags, is_cso);
        return 0;
 }