Some of you may have seen the iwn(4) diff before, but I tweaked it a bit to minimize the diff. Tested iwn(4) and wpi(4) myself. Further tests and/or ok's are welcome.
Index: if_ipw.c =================================================================== RCS file: /cvs/src/sys/dev/pci/if_ipw.c,v retrieving revision 1.107 diff -u -p -r1.107 if_ipw.c --- if_ipw.c 10 Feb 2015 23:25:46 -0000 1.107 +++ if_ipw.c 26 May 2015 20:52:22 -0000 @@ -1143,7 +1143,6 @@ ipw_tx_start(struct ifnet *ifp, struct m struct ieee80211com *ic = &sc->sc_ic; struct ieee80211_frame *wh; struct ieee80211_key *k; - struct mbuf *m1; struct ipw_soft_bd *sbd; struct ipw_soft_hdr *shdr; struct ipw_soft_buf *sbuf; @@ -1208,24 +1207,10 @@ ipw_tx_start(struct ifnet *ifp, struct m } if (error != 0) { /* too many fragments, linearize */ - MGETHDR(m1, M_DONTWAIT, MT_DATA); - if (m1 == NULL) { + if (m_defrag(m, M_DONTWAIT)) { m_freem(m); return ENOBUFS; } - if (m->m_pkthdr.len > MHLEN) { - MCLGET(m1, M_DONTWAIT); - if (!(m1->m_flags & M_EXT)) { - m_freem(m); - m_freem(m1); - return ENOBUFS; - } - } - m_copydata(m, 0, m->m_pkthdr.len, mtod(m1, caddr_t)); - m1->m_pkthdr.len = m1->m_len = m->m_pkthdr.len; - m_freem(m); - m = m1; - error = bus_dmamap_load_mbuf(sc->sc_dmat, sbuf->map, m, BUS_DMA_NOWAIT); if (error != 0) { Index: if_iwi.c =================================================================== RCS file: /cvs/src/sys/dev/pci/if_iwi.c,v retrieving revision 1.124 diff -u -p -r1.124 if_iwi.c --- if_iwi.c 14 Mar 2015 03:38:48 -0000 1.124 +++ if_iwi.c 26 May 2015 20:52:22 -0000 @@ -1250,7 +1250,6 @@ iwi_tx_start(struct ifnet *ifp, struct m struct ieee80211com *ic = &sc->sc_ic; struct ieee80211_frame *wh; struct ieee80211_key *k; - struct mbuf *m1; struct iwi_tx_data *data; struct iwi_tx_desc *desc; struct iwi_tx_ring *txq = &sc->txq[0]; @@ -1317,24 +1316,10 @@ iwi_tx_start(struct ifnet *ifp, struct m } if (error != 0) { /* too many fragments, linearize */ - MGETHDR(m1, M_DONTWAIT, MT_DATA); - if (m1 == NULL) { + if (m_defrag(m0, M_DONTWAIT)) { m_freem(m0); return ENOBUFS; } - if (m0->m_pkthdr.len > MHLEN) { - MCLGET(m1, M_DONTWAIT); - if (!(m1->m_flags & M_EXT)) { - m_freem(m0); - m_freem(m1); - return ENOBUFS; - } - } - m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m1, caddr_t)); - m1->m_pkthdr.len = m1->m_len = m0->m_pkthdr.len; - m_freem(m0); - m0 = m1; - error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m0, BUS_DMA_NOWAIT); if (error != 0) { Index: if_iwn.c =================================================================== RCS file: /cvs/src/sys/dev/pci/if_iwn.c,v retrieving revision 1.142 diff -u -p -r1.142 if_iwn.c --- if_iwn.c 8 Apr 2015 09:29:49 -0000 1.142 +++ if_iwn.c 26 May 2015 20:52:22 -0000 @@ -2750,7 +2750,6 @@ iwn_tx(struct iwn_softc *sc, struct mbuf const struct iwn_rate *rinfo; struct ieee80211_frame *wh; struct ieee80211_key *k = NULL; - struct mbuf *m1; enum ieee80211_edca_ac ac; uint32_t flags; uint16_t qos; @@ -2962,32 +2961,18 @@ iwn_tx(struct iwn_softc *sc, struct mbuf error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m, BUS_DMA_NOWAIT | BUS_DMA_WRITE); + if (error != 0 && error != EFBIG) { + printf("%s: can't map mbuf (error %d)\n", + sc->sc_dev.dv_xname, error); + m_freem(m); + return error; + } if (error != 0) { - if (error != EFBIG) { - printf("%s: can't map mbuf (error %d)\n", - sc->sc_dev.dv_xname, error); - m_freem(m); - return error; - } /* Too many DMA segments, linearize mbuf. */ - MGETHDR(m1, M_DONTWAIT, MT_DATA); - if (m1 == NULL) { + if (m_defrag(m, M_DONTWAIT)) { m_freem(m); return ENOBUFS; } - if (m->m_pkthdr.len > MHLEN) { - MCLGET(m1, M_DONTWAIT); - if (!(m1->m_flags & M_EXT)) { - m_freem(m); - m_freem(m1); - return ENOBUFS; - } - } - m_copydata(m, 0, m->m_pkthdr.len, mtod(m1, caddr_t)); - m1->m_pkthdr.len = m1->m_len = m->m_pkthdr.len; - m_freem(m); - m = m1; - error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m, BUS_DMA_NOWAIT | BUS_DMA_WRITE); if (error != 0) { Index: if_wpi.c =================================================================== RCS file: /cvs/src/sys/dev/pci/if_wpi.c,v retrieving revision 1.126 diff -u -p -r1.126 if_wpi.c --- if_wpi.c 16 Mar 2015 04:09:53 -0000 1.126 +++ if_wpi.c 26 May 2015 20:52:22 -0000 @@ -1655,7 +1655,6 @@ wpi_tx(struct wpi_softc *sc, struct mbuf const struct wpi_rate *rinfo; struct ieee80211_frame *wh; struct ieee80211_key *k = NULL; - struct mbuf *m1; enum ieee80211_edca_ac ac; uint32_t flags; uint16_t qos; @@ -1833,24 +1832,10 @@ wpi_tx(struct wpi_softc *sc, struct mbuf } if (error != 0) { /* Too many DMA segments, linearize mbuf. */ - MGETHDR(m1, M_DONTWAIT, MT_DATA); - if (m1 == NULL) { + if (m_defrag(m, M_DONTWAIT)) { m_freem(m); return ENOBUFS; } - if (m->m_pkthdr.len > MHLEN) { - MCLGET(m1, M_DONTWAIT); - if (!(m1->m_flags & M_EXT)) { - m_freem(m); - m_freem(m1); - return ENOBUFS; - } - } - m_copydata(m, 0, m->m_pkthdr.len, mtod(m1, caddr_t)); - m1->m_pkthdr.len = m1->m_len = m->m_pkthdr.len; - m_freem(m); - m = m1; - error = bus_dmamap_load_mbuf(sc->sc_dmat, data->map, m, BUS_DMA_NOWAIT | BUS_DMA_WRITE); if (error != 0) {