igb: Utilize mbuf's header length to setup TX context

While im here, also fix the case that VLAN hardware tagging is enabled
but IP checksum offloading is not enable.

diff --git a/sys/dev/netif/igb/if_igb.c b/sys/dev/netif/igb/if_igb.c
index feaefcb..a3d695c 100644 (file)
--- a/sys/dev/netif/igb/if_igb.c
+++ b/sys/dev/netif/igb/if_igb.c
@@ -135,8 +135,7 @@ static int  igb_resume(device_t);
 
 static boolean_t igb_is_valid_ether_addr(const uint8_t *);
 static void    igb_setup_ifp(struct igb_softc *);
-static int     igb_txctx_pullup(struct igb_tx_ring *, struct mbuf **);
-static boolean_t igb_txctx(struct igb_tx_ring *, struct mbuf *);
+static boolean_t igb_txcsum_ctx(struct igb_tx_ring *, struct mbuf *);
 static void    igb_add_sysctl(struct igb_softc *);
 static int     igb_sysctl_intr_rate(SYSCTL_HANDLER_ARGS);
 static int     igb_sysctl_msix_rate(SYSCTL_HANDLER_ARGS);
@@ -1824,23 +1823,20 @@ igb_init_tx_unit(struct igb_softc *sc)
 }
 
 static boolean_t
-igb_txctx(struct igb_tx_ring *txr, struct mbuf *mp)
+igb_txcsum_ctx(struct igb_tx_ring *txr, struct mbuf *mp)
 {
        struct e1000_adv_tx_context_desc *TXD;
-       struct igb_tx_buf *txbuf;
        uint32_t vlan_macip_lens, type_tucmd_mlhl, mss_l4len_idx;
-       struct ether_vlan_header *eh;
-       struct ip *ip = NULL;
        int ehdrlen, ctxd, ip_hlen = 0;
-       uint16_t etype, vlantag = 0;
+       uint16_t vlantag = 0;
        boolean_t offload = TRUE;
 
        if ((mp->m_pkthdr.csum_flags & IGB_CSUM_FEATURES) == 0)
                offload = FALSE;
 
        vlan_macip_lens = type_tucmd_mlhl = mss_l4len_idx = 0;
+
        ctxd = txr->next_avail_desc;
-       txbuf = &txr->tx_buf[ctxd];
        TXD = (struct e1000_adv_tx_context_desc *)&txr->tx_base[ctxd];
 
        /*
@@ -1855,51 +1851,16 @@ igb_txctx(struct igb_tx_ring *txr, struct mbuf *mp)
                return FALSE;
        }
 
-       /*
-        * Determine where frame payload starts.
-        * Jump over vlan headers if already present,
-        * helpful for QinQ too.
-        */
-       KASSERT(mp->m_len >= ETHER_HDR_LEN,
-           ("igb_txctx_pullup is not called (eh)?\n"));
-       eh = mtod(mp, struct ether_vlan_header *);
-       if (eh->evl_encap_proto == htons(ETHERTYPE_VLAN)) {
-               KASSERT(mp->m_len >= ETHER_HDR_LEN + EVL_ENCAPLEN,
-                   ("igb_txctx_pullup is not called (evh)?\n"));
-               etype = ntohs(eh->evl_proto);
-               ehdrlen = ETHER_HDR_LEN + EVL_ENCAPLEN;
-       } else {
-               etype = ntohs(eh->evl_encap_proto);
-               ehdrlen = ETHER_HDR_LEN;
-       }
+       ehdrlen = mp->m_pkthdr.csum_lhlen;
+       KASSERT(ehdrlen > 0, ("invalid ether hlen"));
 
        /* Set the ether header length */
        vlan_macip_lens |= ehdrlen << E1000_ADVTXD_MACLEN_SHIFT;
 
-       switch (etype) {
-       case ETHERTYPE_IP:
-               KASSERT(mp->m_len >= ehdrlen + IGB_IPVHL_SIZE,
-                   ("igb_txctx_pullup is not called (eh+ip_vhl)?\n"));
-
-               /* NOTE: We could only safely access ip.ip_vhl part */
-               ip = (struct ip *)(mp->m_data + ehdrlen);
-               ip_hlen = ip->ip_hl << 2;
-
-               if (mp->m_pkthdr.csum_flags & CSUM_IP)
-                       type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_IPV4;
-               break;
-
-#ifdef notyet
-       case ETHERTYPE_IPV6:
-               ip6 = (struct ip6_hdr *)(mp->m_data + ehdrlen);
-               ip_hlen = sizeof(struct ip6_hdr);
-               type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_IPV6;
-               break;
-#endif
-
-       default:
-               offload = FALSE;
-               break;
+       if (mp->m_pkthdr.csum_flags & CSUM_IP) {
+               type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_IPV4;
+               ip_hlen = mp->m_pkthdr.csum_iphlen;
+               KASSERT(ip_hlen > 0, ("invalid ip hlen"));
        }
 
        vlan_macip_lens |= ip_hlen;
@@ -1920,8 +1881,6 @@ igb_txctx(struct igb_tx_ring *txr, struct mbuf *mp)
        TXD->seqnum_seed = htole32(0);
        TXD->mss_l4len_idx = htole32(mss_l4len_idx);
 
-       txbuf->m_head = NULL;
-
        /* We've consumed the first desc, adjust counters */
        if (++ctxd == txr->num_tx_desc)
                ctxd = 0;
@@ -3079,66 +3038,6 @@ igb_intr_shared(void *xsc)
 }
 
 static int
-igb_txctx_pullup(struct igb_tx_ring *txr, struct mbuf **m0)
-{
-       struct mbuf *m = *m0;
-       struct ether_header *eh;
-       int len;
-
-       txr->ctx_try_pullup++;
-
-       len = ETHER_HDR_LEN + IGB_IPVHL_SIZE;
-
-       if (__predict_false(!M_WRITABLE(m))) {
-               if (__predict_false(m->m_len < ETHER_HDR_LEN)) {
-                       txr->ctx_drop1++;
-                       m_freem(m);
-                       *m0 = NULL;
-                       return ENOBUFS;
-               }
-               eh = mtod(m, struct ether_header *);
-
-               if (eh->ether_type == htons(ETHERTYPE_VLAN))
-                       len += EVL_ENCAPLEN;
-
-               if (m->m_len < len) {
-                       txr->ctx_drop2++;
-                       m_freem(m);
-                       *m0 = NULL;
-                       return ENOBUFS;
-               }
-               return 0;
-       }
-
-       if (__predict_false(m->m_len < ETHER_HDR_LEN)) {
-               txr->ctx_pullup1++;
-               m = m_pullup(m, ETHER_HDR_LEN);
-               if (m == NULL) {
-                       txr->ctx_pullup1_failed++;
-                       *m0 = NULL;
-                       return ENOBUFS;
-               }
-               *m0 = m;
-       }
-       eh = mtod(m, struct ether_header *);
-
-       if (eh->ether_type == htons(ETHERTYPE_VLAN))
-               len += EVL_ENCAPLEN;
-
-       if (m->m_len < len) {
-               txr->ctx_pullup2++;
-               m = m_pullup(m, len);
-               if (m == NULL) {
-                       txr->ctx_pullup2_failed++;
-                       *m0 = NULL;
-                       return ENOBUFS;
-               }
-               *m0 = m;
-       }
-       return 0;
-}
-
-static int
 igb_encap(struct igb_tx_ring *txr, struct mbuf **m_headp)
 {
        bus_dma_segment_t segs[IGB_MAX_SCATTER];
@@ -3150,23 +3049,6 @@ igb_encap(struct igb_tx_ring *txr, struct mbuf **m_headp)
        int maxsegs, nsegs, i, j, error, last = 0;
        uint32_t hdrlen = 0;
 
-       if (m_head->m_len < IGB_TXCSUM_MINHL &&
-           ((m_head->m_pkthdr.csum_flags & IGB_CSUM_FEATURES) ||
-            (m_head->m_flags & M_VLANTAG))) {
-               /*
-                * Make sure that ethernet header and ip.ip_hl are in
-                * contiguous memory, since if TXCSUM or VLANTAG is
-                * enabled, later TX context descriptor's setup need
-                * to access ip.ip_hl.
-                */
-               error = igb_txctx_pullup(txr, m_headp);
-               if (error) {
-                       KKASSERT(*m_headp == NULL);
-                       return error;
-               }
-               m_head = *m_headp;
-       }
-
        /* Set basic descriptor constants */
        cmd_type_len |= E1000_ADVTXD_DTYP_DATA;
        cmd_type_len |= E1000_ADVTXD_DCMD_IFCS | E1000_ADVTXD_DCMD_DEXT;
@@ -3218,8 +3100,9 @@ igb_encap(struct igb_tx_ring *txr, struct mbuf **m_headp)
        } else if (igb_tx_ctx_setup(txr, m_head))
                olinfo_status |= E1000_TXD_POPTS_TXSM << 8;
 #else
-       if (igb_txctx(txr, m_head)) {
-               olinfo_status |= (E1000_TXD_POPTS_IXSM << 8);
+       if (igb_txcsum_ctx(txr, m_head)) {
+               if (m_head->m_pkthdr.csum_flags & CSUM_IP)
+                       olinfo_status |= (E1000_TXD_POPTS_IXSM << 8);
                if (m_head->m_pkthdr.csum_flags & (CSUM_UDP | CSUM_TCP))
                        olinfo_status |= (E1000_TXD_POPTS_TXSM << 8);
                txr->tx_nsegs++;