Module Name: src
Committed By: thorpej
Date: Mon Aug 22 16:14:31 UTC 2022
Modified Files:
src/sys/dev/pci: if_age.c
Log Message:
age_encap(): Use m_defrag(), not m_pullup(), to compact an mbuf chain
if it has too many DMA segments. Let the caller handle dispose of the
packet on fatal errors.
To generate a diff of this commit:
cvs rdiff -u -r1.70 -r1.71 src/sys/dev/pci/if_age.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/pci/if_age.c
diff -u src/sys/dev/pci/if_age.c:1.70 src/sys/dev/pci/if_age.c:1.71
--- src/sys/dev/pci/if_age.c:1.70 Tue May 31 08:43:15 2022
+++ src/sys/dev/pci/if_age.c Mon Aug 22 16:14:31 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: if_age.c,v 1.70 2022/05/31 08:43:15 andvar Exp $ */
+/* $NetBSD: if_age.c,v 1.71 2022/08/22 16:14:31 thorpej Exp $ */
/* $OpenBSD: if_age.c,v 1.1 2009/01/16 05:00:34 kevlo Exp $ */
/*-
@@ -31,7 +31,7 @@
/* Driver for Attansic Technology Corp. L1 Gigabit Ethernet. */
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_age.c,v 1.70 2022/05/31 08:43:15 andvar Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_age.c,v 1.71 2022/08/22 16:14:31 thorpej Exp $");
#include "vlan.h"
@@ -98,7 +98,7 @@ static void age_dma_free(struct age_soft
static void age_get_macaddr(struct age_softc *, uint8_t[]);
static void age_phy_reset(struct age_softc *);
-static int age_encap(struct age_softc *, struct mbuf **);
+static int age_encap(struct age_softc *, struct mbuf *);
static void age_init_tx_ring(struct age_softc *);
static int age_init_rx_ring(struct age_softc *);
static void age_init_rr_ring(struct age_softc *);
@@ -1056,7 +1056,7 @@ age_start(struct ifnet *ifp)
{
struct age_softc *sc = ifp->if_softc;
struct mbuf *m_head;
- int enq;
+ int enq, error;
if ((ifp->if_flags & (IFF_RUNNING | IFF_OACTIVE)) != IFF_RUNNING)
return;
@@ -1076,9 +1076,13 @@ age_start(struct ifnet *ifp)
* don't have room, set the OACTIVE flag and wait
* for the NIC to drain the ring.
*/
- if (age_encap(sc, &m_head)) {
- if (m_head == NULL)
- break;
+ if ((error = age_encap(sc, m_head)) != 0) {
+ if (error == EFBIG) {
+ /* This is fatal for the packet. */
+ m_freem(m_head);
+ if_statinc(ifp, if_oerrors);
+ continue;
+ }
IF_PREPEND(&ifp->if_snd, m_head);
ifp->if_flags |= IFF_OACTIVE;
break;
@@ -1213,16 +1217,14 @@ age_resume(device_t dv, const pmf_qual_t
}
static int
-age_encap(struct age_softc *sc, struct mbuf **m_head)
+age_encap(struct age_softc *sc, struct mbuf * const m)
{
struct age_txdesc *txd, *txd_last;
struct tx_desc *desc;
- struct mbuf *m;
bus_dmamap_t map;
uint32_t cflags, poff, vtag;
int error, i, nsegs, prod;
- m = *m_head;
cflags = vtag = 0;
poff = 0;
@@ -1231,40 +1233,31 @@ age_encap(struct age_softc *sc, struct m
txd_last = txd;
map = txd->tx_dmamap;
- error = bus_dmamap_load_mbuf(sc->sc_dmat, map, *m_head, BUS_DMA_NOWAIT);
-
+ error = bus_dmamap_load_mbuf(sc->sc_dmat, map, m, BUS_DMA_NOWAIT);
if (error == EFBIG) {
- error = 0;
-
- *m_head = m_pullup(*m_head, MHLEN);
- if (*m_head == NULL) {
- printf("%s: can't defrag TX mbuf\n",
- device_xname(sc->sc_dev));
- return ENOBUFS;
- }
-
- error = bus_dmamap_load_mbuf(sc->sc_dmat, map, *m_head,
+ struct mbuf *mnew = m_defrag(m, M_NOWAIT);
+ if (mnew != NULL) {
+ KASSERT(m == mnew);
+ error = bus_dmamap_load_mbuf(sc->sc_dmat, map, mnew,
BUS_DMA_NOWAIT);
-
- if (error != 0) {
- printf("%s: could not load defragged TX mbuf\n",
- device_xname(sc->sc_dev));
- m_freem(*m_head);
- *m_head = NULL;
+ } else {
+ /* Just drop if we can't defrag. */
+ error = EFBIG;
+ }
+ if (error) {
+ if (error == EFBIG) {
+ printf("%s: Tx packet consumes too many "
+ "DMA segments, dropping...\n",
+ device_xname(sc->sc_dev));
+ }
return error;
}
} else if (error) {
- printf("%s: could not load TX mbuf\n", device_xname(sc->sc_dev));
return error;
}
nsegs = map->dm_nsegs;
-
- if (nsegs == 0) {
- m_freem(*m_head);
- *m_head = NULL;
- return EIO;
- }
+ KASSERT(nsegs != 0);
/* Check descriptor overrun. */
if (sc->age_cdata.age_tx_cnt + nsegs >= AGE_TX_RING_CNT - 2) {
@@ -1274,7 +1267,6 @@ age_encap(struct age_softc *sc, struct m
bus_dmamap_sync(sc->sc_dmat, map, 0, map->dm_mapsize,
BUS_DMASYNC_PREWRITE);
- m = *m_head;
/* Configure Tx IP/TCP/UDP checksum offload. */
if ((m->m_pkthdr.csum_flags & AGE_CSUM_FEATURES) != 0) {
cflags |= AGE_TD_CSUM;
