From: Alexey Kardashevskiy Date: Wed, 14 Aug 2013 09:19:01 +0000 (+1000) Subject: Revert "cxgb3: Check and handle the dma mapping errors" X-Git-Tag: v4.0~3510^2~9 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=728e2ccaa3c4d20cf4d54b73a47956bf4d334a9f;p=platform%2Fkernel%2Flinux-amlogic.git Revert "cxgb3: Check and handle the dma mapping errors" This reverts commit f83331bab149e29fa2c49cf102c0cd8c3f1ce9f9. As the tests PPC64 (powernv platform) show, IOMMU pages are leaking when transferring big amount of small packets (<=64 bytes), "ping -f" and waiting for 15 seconds is the simplest way to confirm the bug. Cc: Linus Torvalds Cc: Santosh Rastapur Cc: Jay Fenlason Cc: David S. Miller Cc: Divy Le ray Signed-off-by: Alexey Kardashevskiy Acked-by: Divy Le Ray Signed-off-by: David S. Miller --- diff --git a/drivers/net/ethernet/chelsio/cxgb3/sge.c b/drivers/net/ethernet/chelsio/cxgb3/sge.c index 687ec4a..9c89dc8 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb3/sge.c @@ -455,11 +455,6 @@ static int alloc_pg_chunk(struct adapter *adapter, struct sge_fl *q, q->pg_chunk.offset = 0; mapping = pci_map_page(adapter->pdev, q->pg_chunk.page, 0, q->alloc_size, PCI_DMA_FROMDEVICE); - if (unlikely(pci_dma_mapping_error(adapter->pdev, mapping))) { - __free_pages(q->pg_chunk.page, order); - q->pg_chunk.page = NULL; - return -EIO; - } q->pg_chunk.mapping = mapping; } sd->pg_chunk = q->pg_chunk; @@ -954,75 +949,40 @@ static inline unsigned int calc_tx_descs(const struct sk_buff *skb) return flits_to_desc(flits); } - -/* map_skb - map a packet main body and its page fragments - * @pdev: the PCI device - * @skb: the packet - * @addr: placeholder to save the mapped addresses - * - * map the main body of an sk_buff and its page fragments, if any. - */ -static int map_skb(struct pci_dev *pdev, const struct sk_buff *skb, - dma_addr_t *addr) -{ - const skb_frag_t *fp, *end; - const struct skb_shared_info *si; - - *addr = pci_map_single(pdev, skb->data, skb_headlen(skb), - PCI_DMA_TODEVICE); - if (pci_dma_mapping_error(pdev, *addr)) - goto out_err; - - si = skb_shinfo(skb); - end = &si->frags[si->nr_frags]; - - for (fp = si->frags; fp < end; fp++) { - *++addr = skb_frag_dma_map(&pdev->dev, fp, 0, skb_frag_size(fp), - DMA_TO_DEVICE); - if (pci_dma_mapping_error(pdev, *addr)) - goto unwind; - } - return 0; - -unwind: - while (fp-- > si->frags) - dma_unmap_page(&pdev->dev, *--addr, skb_frag_size(fp), - DMA_TO_DEVICE); - - pci_unmap_single(pdev, addr[-1], skb_headlen(skb), PCI_DMA_TODEVICE); -out_err: - return -ENOMEM; -} - /** - * write_sgl - populate a scatter/gather list for a packet + * make_sgl - populate a scatter/gather list for a packet * @skb: the packet * @sgp: the SGL to populate * @start: start address of skb main body data to include in the SGL * @len: length of skb main body data to include in the SGL - * @addr: the list of the mapped addresses + * @pdev: the PCI device * - * Copies the scatter/gather list for the buffers that make up a packet + * Generates a scatter/gather list for the buffers that make up a packet * and returns the SGL size in 8-byte words. The caller must size the SGL * appropriately. */ -static inline unsigned int write_sgl(const struct sk_buff *skb, +static inline unsigned int make_sgl(const struct sk_buff *skb, struct sg_ent *sgp, unsigned char *start, - unsigned int len, const dma_addr_t *addr) + unsigned int len, struct pci_dev *pdev) { - unsigned int i, j = 0, k = 0, nfrags; + dma_addr_t mapping; + unsigned int i, j = 0, nfrags; if (len) { + mapping = pci_map_single(pdev, start, len, PCI_DMA_TODEVICE); sgp->len[0] = cpu_to_be32(len); - sgp->addr[j++] = cpu_to_be64(addr[k++]); + sgp->addr[0] = cpu_to_be64(mapping); + j = 1; } nfrags = skb_shinfo(skb)->nr_frags; for (i = 0; i < nfrags; i++) { const skb_frag_t *frag = &skb_shinfo(skb)->frags[i]; + mapping = skb_frag_dma_map(&pdev->dev, frag, 0, skb_frag_size(frag), + DMA_TO_DEVICE); sgp->len[j] = cpu_to_be32(skb_frag_size(frag)); - sgp->addr[j] = cpu_to_be64(addr[k++]); + sgp->addr[j] = cpu_to_be64(mapping); j ^= 1; if (j == 0) ++sgp; @@ -1178,7 +1138,7 @@ static void write_tx_pkt_wr(struct adapter *adap, struct sk_buff *skb, const struct port_info *pi, unsigned int pidx, unsigned int gen, struct sge_txq *q, unsigned int ndesc, - unsigned int compl, const dma_addr_t *addr) + unsigned int compl) { unsigned int flits, sgl_flits, cntrl, tso_info; struct sg_ent *sgp, sgl[MAX_SKB_FRAGS / 2 + 1]; @@ -1236,7 +1196,7 @@ static void write_tx_pkt_wr(struct adapter *adap, struct sk_buff *skb, } sgp = ndesc == 1 ? (struct sg_ent *)&d->flit[flits] : sgl; - sgl_flits = write_sgl(skb, sgp, skb->data, skb_headlen(skb), addr); + sgl_flits = make_sgl(skb, sgp, skb->data, skb_headlen(skb), adap->pdev); write_wr_hdr_sgl(ndesc, skb, d, pidx, q, sgl, flits, sgl_flits, gen, htonl(V_WR_OP(FW_WROPCODE_TUNNEL_TX_PKT) | compl), @@ -1267,7 +1227,6 @@ netdev_tx_t t3_eth_xmit(struct sk_buff *skb, struct net_device *dev) struct netdev_queue *txq; struct sge_qset *qs; struct sge_txq *q; - dma_addr_t addr[MAX_SKB_FRAGS + 1]; /* * The chip min packet length is 9 octets but play safe and reject @@ -1296,11 +1255,6 @@ netdev_tx_t t3_eth_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_BUSY; } - if (unlikely(map_skb(adap->pdev, skb, addr) < 0)) { - dev_kfree_skb(skb); - return NETDEV_TX_OK; - } - q->in_use += ndesc; if (unlikely(credits - ndesc < q->stop_thres)) { t3_stop_tx_queue(txq, qs, q); @@ -1358,7 +1312,7 @@ netdev_tx_t t3_eth_xmit(struct sk_buff *skb, struct net_device *dev) if (likely(!skb_shared(skb))) skb_orphan(skb); - write_tx_pkt_wr(adap, skb, pi, pidx, gen, q, ndesc, compl, addr); + write_tx_pkt_wr(adap, skb, pi, pidx, gen, q, ndesc, compl); check_ring_tx_db(adap, q); return NETDEV_TX_OK; } @@ -1623,8 +1577,7 @@ static void setup_deferred_unmapping(struct sk_buff *skb, struct pci_dev *pdev, */ static void write_ofld_wr(struct adapter *adap, struct sk_buff *skb, struct sge_txq *q, unsigned int pidx, - unsigned int gen, unsigned int ndesc, - const dma_addr_t *addr) + unsigned int gen, unsigned int ndesc) { unsigned int sgl_flits, flits; struct work_request_hdr *from; @@ -1645,9 +1598,9 @@ static void write_ofld_wr(struct adapter *adap, struct sk_buff *skb, flits = skb_transport_offset(skb) / 8; sgp = ndesc == 1 ? (struct sg_ent *)&d->flit[flits] : sgl; - sgl_flits = write_sgl(skb, sgp, skb_transport_header(skb), - skb_tail_pointer(skb) - - skb_transport_header(skb), addr); + sgl_flits = make_sgl(skb, sgp, skb_transport_header(skb), + skb->tail - skb->transport_header, + adap->pdev); if (need_skb_unmap()) { setup_deferred_unmapping(skb, adap->pdev, sgp, sgl_flits); skb->destructor = deferred_unmap_destructor; @@ -1705,11 +1658,6 @@ again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); goto again; } - if (map_skb(adap->pdev, skb, (dma_addr_t *)skb->head)) { - spin_unlock(&q->lock); - return NET_XMIT_SUCCESS; - } - gen = q->gen; q->in_use += ndesc; pidx = q->pidx; @@ -1720,7 +1668,7 @@ again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); } spin_unlock(&q->lock); - write_ofld_wr(adap, skb, q, pidx, gen, ndesc, (dma_addr_t *)skb->head); + write_ofld_wr(adap, skb, q, pidx, gen, ndesc); check_ring_tx_db(adap, q); return NET_XMIT_SUCCESS; } @@ -1738,7 +1686,6 @@ static void restart_offloadq(unsigned long data) struct sge_txq *q = &qs->txq[TXQ_OFLD]; const struct port_info *pi = netdev_priv(qs->netdev); struct adapter *adap = pi->adapter; - unsigned int written = 0; spin_lock(&q->lock); again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); @@ -1758,14 +1705,10 @@ again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); break; } - if (map_skb(adap->pdev, skb, (dma_addr_t *)skb->head)) - break; - gen = q->gen; q->in_use += ndesc; pidx = q->pidx; q->pidx += ndesc; - written += ndesc; if (q->pidx >= q->size) { q->pidx -= q->size; q->gen ^= 1; @@ -1773,8 +1716,7 @@ again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); __skb_unlink(skb, &q->sendq); spin_unlock(&q->lock); - write_ofld_wr(adap, skb, q, pidx, gen, ndesc, - (dma_addr_t *)skb->head); + write_ofld_wr(adap, skb, q, pidx, gen, ndesc); spin_lock(&q->lock); } spin_unlock(&q->lock); @@ -1784,9 +1726,8 @@ again: reclaim_completed_tx(adap, q, TX_RECLAIM_CHUNK); set_bit(TXQ_LAST_PKT_DB, &q->flags); #endif wmb(); - if (likely(written)) - t3_write_reg(adap, A_SG_KDOORBELL, - F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); + t3_write_reg(adap, A_SG_KDOORBELL, + F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id)); } /**