From 7c20ac5e151fd7bf876c5ae92b96c3da95cd6dcd Mon Sep 17 00:00:00 2001 From: bschmidt Date: Sat, 16 Apr 2011 10:32:46 +0000 Subject: Rewrite DMA segment handling to be more inline with the OpenBSD code. Also change the m_len == 0 hack to have less code churn. --- sys/dev/iwn/if_iwn.c | 108 +++++++++++++++++++++++++++++---------------------- 1 file changed, 62 insertions(+), 46 deletions(-) diff --git a/sys/dev/iwn/if_iwn.c b/sys/dev/iwn/if_iwn.c index 6d62f3a..0f35d6c 100644 --- a/sys/dev/iwn/if_iwn.c +++ b/sys/dev/iwn/if_iwn.c @@ -2906,8 +2906,8 @@ iwn_tx_data(struct iwn_softc *sc, struct mbuf *m, struct ieee80211_node *ni, struct iwn_cmd_data *tx; struct ieee80211_frame *wh; struct ieee80211_key *k = NULL; - struct mbuf *mnew; - bus_dma_segment_t segs[IWN_MAX_SCATTER]; + struct mbuf *m1; + bus_dma_segment_t *seg, segs[IWN_MAX_SCATTER]; uint32_t flags; u_int hdrlen; int totlen, error, pad, nsegs = 0, i, rate; @@ -3063,26 +3063,30 @@ iwn_tx_data(struct iwn_softc *sc, struct mbuf *m, struct ieee80211_node *ni, tx->security = 0; tx->flags = htole32(flags); - if (m->m_len > 0) { - error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, - m, segs, &nsegs, BUS_DMA_NOWAIT); - if (error == EFBIG) { - /* too many fragments, linearize */ - mnew = m_collapse(m, M_DONTWAIT, IWN_MAX_SCATTER); - if (mnew == NULL) { - device_printf(sc->sc_dev, - "%s: could not defrag mbuf\n", __func__); - m_freem(m); - return ENOBUFS; - } - m = mnew; - error = bus_dmamap_load_mbuf_sg(ring->data_dmat, - data->map, m, segs, &nsegs, BUS_DMA_NOWAIT); + error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, m, segs, + &nsegs, BUS_DMA_NOWAIT); + if (error != 0) { + if (error != EFBIG) { + device_printf(sc->sc_dev, + "%s: can't map mbuf (error %d)\n", __func__, error); + m_freem(m); + return error; } + /* Too many DMA segments, linearize mbuf. */ + m1 = m_collapse(m, M_DONTWAIT, IWN_MAX_SCATTER); + if (m1 == NULL) { + device_printf(sc->sc_dev, + "%s: could not defrag mbuf\n", __func__); + m_freem(m); + return ENOBUFS; + } + m = m1; + + error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, m, + segs, &nsegs, BUS_DMA_NOWAIT); if (error != 0) { device_printf(sc->sc_dev, - "%s: bus_dmamap_load_mbuf_sg failed, error %d\n", - __func__, error); + "%s: can't map mbuf (error %d)\n", __func__, error); m_freem(m); return error; } @@ -3095,16 +3099,20 @@ iwn_tx_data(struct iwn_softc *sc, struct mbuf *m, struct ieee80211_node *ni, __func__, ring->qid, ring->cur, m->m_pkthdr.len, nsegs); /* Fill TX descriptor. */ - desc->nsegs = 1 + nsegs; + desc->nsegs = 1; + if (m->m_len != 0) + desc->nsegs += nsegs; /* First DMA segment is used by the TX command. */ desc->segs[0].addr = htole32(IWN_LOADDR(data->cmd_paddr)); desc->segs[0].len = htole16(IWN_HIADDR(data->cmd_paddr) | (4 + sizeof (*tx) + hdrlen + pad) << 4); /* Other DMA segments are for data payload. */ + seg = &segs[0]; for (i = 1; i <= nsegs; i++) { - desc->segs[i].addr = htole32(IWN_LOADDR(segs[i - 1].ds_addr)); - desc->segs[i].len = htole16(IWN_HIADDR(segs[i - 1].ds_addr) | - segs[i - 1].ds_len << 4); + desc->segs[i].addr = htole32(IWN_LOADDR(seg->ds_addr)); + desc->segs[i].len = htole16(IWN_HIADDR(seg->ds_addr) | + seg->ds_len << 4); + seg++; } bus_dmamap_sync(ring->data_dmat, data->map, BUS_DMASYNC_PREWRITE); @@ -3144,8 +3152,8 @@ iwn_tx_data_raw(struct iwn_softc *sc, struct mbuf *m, struct ieee80211_frame *wh; struct iwn_tx_desc *desc; struct iwn_tx_data *data; - struct mbuf *mnew; - bus_dma_segment_t segs[IWN_MAX_SCATTER]; + struct mbuf *m1; + bus_dma_segment_t *seg, segs[IWN_MAX_SCATTER]; uint32_t flags; u_int hdrlen; int totlen, error, pad, nsegs = 0, i, rate; @@ -3256,26 +3264,30 @@ iwn_tx_data_raw(struct iwn_softc *sc, struct mbuf *m, tx->security = 0; tx->flags = htole32(flags); - if (m->m_len > 0) { - error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, - m, segs, &nsegs, BUS_DMA_NOWAIT); - if (error == EFBIG) { - /* Too many fragments, linearize. */ - mnew = m_collapse(m, M_DONTWAIT, IWN_MAX_SCATTER); - if (mnew == NULL) { - device_printf(sc->sc_dev, - "%s: could not defrag mbuf\n", __func__); - m_freem(m); - return ENOBUFS; - } - m = mnew; - error = bus_dmamap_load_mbuf_sg(ring->data_dmat, - data->map, m, segs, &nsegs, BUS_DMA_NOWAIT); + error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, m, segs, + &nsegs, BUS_DMA_NOWAIT); + if (error != 0) { + if (error != EFBIG) { + device_printf(sc->sc_dev, + "%s: can't map mbuf (error %d)\n", __func__, error); + m_freem(m); + return error; } + /* Too many DMA segments, linearize mbuf. */ + m1 = m_collapse(m, M_DONTWAIT, IWN_MAX_SCATTER); + if (m1 == NULL) { + device_printf(sc->sc_dev, + "%s: could not defrag mbuf\n", __func__); + m_freem(m); + return ENOBUFS; + } + m = m1; + + error = bus_dmamap_load_mbuf_sg(ring->data_dmat, data->map, m, + segs, &nsegs, BUS_DMA_NOWAIT); if (error != 0) { device_printf(sc->sc_dev, - "%s: bus_dmamap_load_mbuf_sg failed, error %d\n", - __func__, error); + "%s: can't map mbuf (error %d)\n", __func__, error); m_freem(m); return error; } @@ -3288,16 +3300,20 @@ iwn_tx_data_raw(struct iwn_softc *sc, struct mbuf *m, __func__, ring->qid, ring->cur, m->m_pkthdr.len, nsegs); /* Fill TX descriptor. */ - desc->nsegs = 1 + nsegs; + desc->nsegs = 1; + if (m->m_len != 0) + desc->nsegs += nsegs; /* First DMA segment is used by the TX command. */ desc->segs[0].addr = htole32(IWN_LOADDR(data->cmd_paddr)); desc->segs[0].len = htole16(IWN_HIADDR(data->cmd_paddr) | (4 + sizeof (*tx) + hdrlen + pad) << 4); /* Other DMA segments are for data payload. */ + seg = &segs[0]; for (i = 1; i <= nsegs; i++) { - desc->segs[i].addr = htole32(IWN_LOADDR(segs[i - 1].ds_addr)); - desc->segs[i].len = htole16(IWN_HIADDR(segs[i - 1].ds_addr) | - segs[i - 1].ds_len << 4); + desc->segs[i].addr = htole32(IWN_LOADDR(seg->ds_addr)); + desc->segs[i].len = htole16(IWN_HIADDR(seg->ds_addr) | + seg->ds_len << 4); + seg++; } bus_dmamap_sync(ring->data_dmat, data->map, BUS_DMASYNC_PREWRITE); -- cgit v1.1