svn commit: r207251 - head/sys/dev/ale

[Pyun YongHyeon]

Author: yongari
Date: Mon Apr 26 21:08:15 2010
New Revision: 207251
URL: http://svn.freebsd.org/changeset/base/207251

Log:
  It seems ale(4) controllers do not like to see TCP payload in the
  first descriptor in TSO case. Otherwise controller can generate bad
  frames during TSO. To address it, make sure to pull up ethernet +
  IP + TCP header with options in first buffer. Also ensure the
  buffer length of the first descriptor for TSO covers entire ethernet
  + IP + TCP with options and setup additional Tx descriptor if the
  first buffer includes TCP payload.
  
  Tested by:	Amar Takhar <verm <> darkbeer dot org >
  MFC after:	1 week

Modified:
  head/sys/dev/ale/if_ale.c

Modified: head/sys/dev/ale/if_ale.c
==============================================================================
--- head/sys/dev/ale/if_ale.c	Mon Apr 26 20:55:03 2010	(r207250)
+++ head/sys/dev/ale/if_ale.c	Mon Apr 26 21:08:15 2010	(r207251)
@@ -1585,7 +1585,7 @@ ale_encap(struct ale_softc *sc, struct m
 	struct tcphdr *tcp;
 	bus_dma_segment_t txsegs[ALE_MAXTXSEGS];
 	bus_dmamap_t map;
-	uint32_t cflags, ip_off, poff, vtag;
+	uint32_t cflags, hdrlen, ip_off, poff, vtag;
 	int error, i, nsegs, prod, si;
 
 	ALE_LOCK_ASSERT(sc);
@@ -1678,6 +1678,11 @@ ale_encap(struct ale_softc *sc, struct m
 				return (ENOBUFS);
 			}
 			tcp = (struct tcphdr *)(mtod(m, char *) + poff);
+			m = m_pullup(m, poff + (tcp->th_off << 2));
+			if (m == NULL) {
+				*m_head = NULL;
+				return (ENOBUFS);
+			}
 			/*
 			 * AR81xx requires IP/TCP header size and offset as
 			 * well as TCP pseudo checksum which complicates
@@ -1730,7 +1735,7 @@ ale_encap(struct ale_softc *sc, struct m
 	}
 
 	/* Check descriptor overrun. */
-	if (sc->ale_cdata.ale_tx_cnt + nsegs >= ALE_TX_RING_CNT - 2) {
+	if (sc->ale_cdata.ale_tx_cnt + nsegs >= ALE_TX_RING_CNT - 3) {
 		bus_dmamap_unload(sc->ale_cdata.ale_tx_tag, map);
 		return (ENOBUFS);
 	}
@@ -1782,8 +1787,32 @@ ale_encap(struct ale_softc *sc, struct m
 		cflags |= ALE_TD_INSERT_VLAN_TAG;
 	}
 
-	desc = NULL;
-	for (i = 0; i < nsegs; i++) {
+	i = 0;
+	if ((m->m_pkthdr.csum_flags & CSUM_TSO) != 0) {
+		/*
+		 * Make sure the first fragment contains
+		 * only ethernet and IP/TCP header with options.
+		 */
+		hdrlen =  poff + (tcp->th_off << 2);
+		desc = &sc->ale_cdata.ale_tx_ring[prod];
+		desc->addr = htole64(txsegs[i].ds_addr);
+		desc->len = htole32(ALE_TX_BYTES(hdrlen) | vtag);
+		desc->flags = htole32(cflags);
+		sc->ale_cdata.ale_tx_cnt++;
+		ALE_DESC_INC(prod, ALE_TX_RING_CNT);
+		if (m->m_len - hdrlen > 0) {
+			/* Handle remaining payload of the first fragment. */
+			desc = &sc->ale_cdata.ale_tx_ring[prod];
+			desc->addr = htole64(txsegs[i].ds_addr + hdrlen);
+			desc->len = htole32(ALE_TX_BYTES(m->m_len - hdrlen) |
+			    vtag);
+			desc->flags = htole32(cflags);
+			sc->ale_cdata.ale_tx_cnt++;
+			ALE_DESC_INC(prod, ALE_TX_RING_CNT);
+		}
+		i = 1;
+	}
+	for (; i < nsegs; i++) {
 		desc = &sc->ale_cdata.ale_tx_ring[prod];
 		desc->addr = htole64(txsegs[i].ds_addr);
 		desc->len = htole32(ALE_TX_BYTES(txsegs[i].ds_len) | vtag);