git: 8ee1cc4a7f2e - main - Revert "vtnet: Better adjust for ethernet alignment."

The branch main has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=8ee1cc4a7f2e0a3fb9cb4f9514da07f2572a7f4c

commit 8ee1cc4a7f2e0a3fb9cb4f9514da07f2572a7f4c
Author:     Warner Losh <imp@FreeBSD.org>
AuthorDate: 2023-12-28 17:20:24 +0000
Commit:     Warner Losh <imp@FreeBSD.org>
CommitDate: 2023-12-28 17:22:14 +0000

    Revert "vtnet: Better adjust for ethernet alignment."
    
    This reverts commit e9da71cd35d46ca13da4396d99e0af1703290e68.
    
    This was inadvertantly pushed and turns out ot be not quite right.
    
    Requested by: markj
---
 sys/dev/virtio/network/if_vtnet.c | 31 +++----------------------------
 1 file changed, 3 insertions(+), 28 deletions(-)

diff --git a/sys/dev/virtio/network/if_vtnet.c b/sys/dev/virtio/network/if_vtnet.c
index db7a1a18ebc2..360176e4f845 100644
--- a/sys/dev/virtio/network/if_vtnet.c
+++ b/sys/dev/virtio/network/if_vtnet.c
@@ -1532,8 +1532,8 @@ vtnet_rx_alloc_buf(struct vtnet_softc *sc, int nbufs, struct mbuf **m_tailp)
 			m_freem(m_head);
 			return (NULL);
 		}
-
 		m->m_len = size;
+		m_adj(m, ETHER_ALIGN);
 		if (m_head != NULL) {
 			m_tail->m_next = m;
 			m_tail = m;
@@ -1587,15 +1587,6 @@ vtnet_rxq_replace_lro_nomrg_buf(struct vtnet_rxq *rxq, struct mbuf *m0,
 		    ("%s: mbuf size %d not expected cluster size %d", __func__,
 		    m->m_len, clustersz));
 
-#ifdef __NO_STRICT_ALIGNMENT
-		/*
-		 * Need to offset the first mbuf in this chain to align the IP
-		 * structure because this host requires strict alignment.
-		 */
-		if (m_prev == NULL) {
-			m_adj(m, ETHER_ALIGN);
-		}
-#endif
 		m->m_len = MIN(m->m_len, len);
 		len -= m->m_len;
 
@@ -1664,13 +1655,6 @@ vtnet_rxq_replace_buf(struct vtnet_rxq *rxq, struct mbuf *m, int len)
 	if (m_new == NULL)
 		return (ENOBUFS);
 
-#ifdef __NO_STRICT_ALIGNMENT
-	/*
-	 * Need to offset the first mbuf in this chain to align the IP
-	 * structure because this host requires strict alignment.
-	 */
-	m_adj(m_new, ETHER_ALIGN);
-#endif
 	error = vtnet_rxq_enqueue_buf(rxq, m_new);
 	if (error) {
 		sc->vtnet_stats.rx_enq_replacement_failed++;
@@ -1738,13 +1722,6 @@ vtnet_rxq_new_buf(struct vtnet_rxq *rxq)
 	if (m == NULL)
 		return (ENOBUFS);
 
-#ifdef __NO_STRICT_ALIGNMENT
-	/*
-	 * Need to offset the first mbuf in this chain to align the IP
-	 * structure because this host requires strict alignment.
-	 */
-	m_adj(m, ETHER_ALIGN);
-#endif
 	error = vtnet_rxq_enqueue_buf(rxq, m);
 	if (error)
 		m_freem(m);
@@ -1930,10 +1907,8 @@ vtnet_rxq_discard_buf(struct vtnet_rxq *rxq, struct mbuf *m)
 	int error __diagused;
 
 	/*
-	 * Requeue the discarded mbuf. This should always be successful since it
-	 * was just dequeued. There's no need to adjust for ethernet alignment
-	 * here on strict alignment hosts because we're requeueing a packet
-	 * already adjusted.
+	 * Requeue the discarded mbuf. This should always be successful
+	 * since it was just dequeued.
 	 */
 	error = vtnet_rxq_enqueue_buf(rxq, m);
 	KASSERT(error == 0,