Module Name: src
Committed By: thorpej
Date: Mon Aug 22 15:39:26 UTC 2022
Modified Files:
src/sys/dev/pci: if_ale.c
Log Message:
ale_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 -r1.40 -r1.41 src/sys/dev/pci/if_ale.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_ale.c
diff -u src/sys/dev/pci/if_ale.c:1.40 src/sys/dev/pci/if_ale.c:1.41
--- src/sys/dev/pci/if_ale.c:1.40 Sun Mar 1 02:28:14 2020
+++ src/sys/dev/pci/if_ale.c Mon Aug 22 15:39:26 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: if_ale.c,v 1.40 2020/03/01 02:28:14 thorpej Exp $ */
+/* $NetBSD: if_ale.c,v 1.41 2022/08/22 15:39:26 thorpej Exp $ */
/*-
* Copyright (c) 2008, Pyun YongHyeon <yong...@freebsd.org>
@@ -32,7 +32,7 @@
/* Driver for Atheros AR8121/AR8113/AR8114 PCIe Ethernet. */
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_ale.c,v 1.40 2020/03/01 02:28:14 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_ale.c,v 1.41 2022/08/22 15:39:26 thorpej Exp $");
#include "vlan.h"
@@ -102,7 +102,7 @@ static void ale_txeof(struct ale_softc *
static int ale_dma_alloc(struct ale_softc *);
static void ale_dma_free(struct ale_softc *);
-static int ale_encap(struct ale_softc *, struct mbuf **);
+static int ale_encap(struct ale_softc *, struct mbuf *);
static void ale_init_rx_pages(struct ale_softc *);
static void ale_init_tx_ring(struct ale_softc *);
@@ -908,16 +908,14 @@ ale_dma_free(struct ale_softc *sc)
}
static int
-ale_encap(struct ale_softc *sc, struct mbuf **m_head)
+ale_encap(struct ale_softc *sc, struct mbuf * const m)
{
struct ale_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;
@@ -926,39 +924,26 @@ ale_encap(struct ale_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",
+ 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 (mnew == NULL || error == EFBIG) {
+ printf("%s: Tx packet consumes too many "
+ "DMA segments, dropping...\n",
device_xname(sc->sc_dev));
- return ENOBUFS;
+ return EFBIG;
}
-
- error = bus_dmamap_load_mbuf(sc->sc_dmat, map, *m_head,
- 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;
- return error;
- }
- } else if (error) {
- printf("%s: could not load TX mbuf\n", device_xname(sc->sc_dev));
+ } else if (error != 0) {
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->ale_cdata.ale_tx_cnt + nsegs >= ALE_TX_RING_CNT - 2) {
@@ -968,7 +953,6 @@ ale_encap(struct ale_softc *sc, struct m
bus_dmamap_sync(sc->sc_dmat, map, 0, map->dm_mapsize,
BUS_DMASYNC_PREWRITE);
- m = *m_head;
/* Configure Tx checksum offload. */
if ((m->m_pkthdr.csum_flags & ALE_CSUM_FEATURES) != 0) {
/*
@@ -1044,7 +1028,7 @@ ale_start(struct ifnet *ifp)
{
struct ale_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;
@@ -1064,9 +1048,13 @@ ale_start(struct ifnet *ifp)
* don't have room, set the OACTIVE flag and wait
* for the NIC to drain the ring.
*/
- if (ale_encap(sc, &m_head)) {
- if (m_head == NULL)
- break;
+ if ((error = ale_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;
