From bc7b3a36ba02e4053ca38653e6a753082d9add03 Mon Sep 17 00:00:00 2001 From: Shirley Ma Date: Wed, 23 Apr 2008 11:55:45 -0700 Subject: IPoIB: Handle 4K IB MTU for UD (datagram) mode This patch enables IPoIB to use 4K UD messages (when the underlying device and fabrics support a 4K MTU) by using two scatter buffers when PAGE_SIZE is less than or equal to thhe HCA IB MTU size. The first buffer is for IPoIB header + GRH header, and the second buffer is the IPoIB payload, which is 4K-4. Signed-off-by: Shirley Ma Signed-off-by: Roland Dreier --- drivers/infiniband/ulp/ipoib/ipoib_ib.c | 125 ++++++++++++++++++++++---------- 1 file changed, 88 insertions(+), 37 deletions(-) (limited to 'drivers/infiniband/ulp/ipoib/ipoib_ib.c') diff --git a/drivers/infiniband/ulp/ipoib/ipoib_ib.c b/drivers/infiniband/ulp/ipoib/ipoib_ib.c index 0205eb7c1bd..7cf1fa7074a 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_ib.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_ib.c @@ -89,28 +89,59 @@ void ipoib_free_ah(struct kref *kref) spin_unlock_irqrestore(&priv->lock, flags); } +static void ipoib_ud_dma_unmap_rx(struct ipoib_dev_priv *priv, + u64 mapping[IPOIB_UD_RX_SG]) +{ + if (ipoib_ud_need_sg(priv->max_ib_mtu)) { + ib_dma_unmap_single(priv->ca, mapping[0], IPOIB_UD_HEAD_SIZE, + DMA_FROM_DEVICE); + ib_dma_unmap_page(priv->ca, mapping[1], PAGE_SIZE, + DMA_FROM_DEVICE); + } else + ib_dma_unmap_single(priv->ca, mapping[0], + IPOIB_UD_BUF_SIZE(priv->max_ib_mtu), + DMA_FROM_DEVICE); +} + +static void ipoib_ud_skb_put_frags(struct ipoib_dev_priv *priv, + struct sk_buff *skb, + unsigned int length) +{ + if (ipoib_ud_need_sg(priv->max_ib_mtu)) { + skb_frag_t *frag = &skb_shinfo(skb)->frags[0]; + unsigned int size; + /* + * There is only two buffers needed for max_payload = 4K, + * first buf size is IPOIB_UD_HEAD_SIZE + */ + skb->tail += IPOIB_UD_HEAD_SIZE; + skb->len += length; + + size = length - IPOIB_UD_HEAD_SIZE; + + frag->size = size; + skb->data_len += size; + skb->truesize += size; + } else + skb_put(skb, length); + +} + static int ipoib_ib_post_receive(struct net_device *dev, int id) { struct ipoib_dev_priv *priv = netdev_priv(dev); - struct ib_sge list; - struct ib_recv_wr param; struct ib_recv_wr *bad_wr; int ret; - list.addr = priv->rx_ring[id].mapping; - list.length = IPOIB_BUF_SIZE; - list.lkey = priv->mr->lkey; + priv->rx_wr.wr_id = id | IPOIB_OP_RECV; + priv->rx_sge[0].addr = priv->rx_ring[id].mapping[0]; + priv->rx_sge[1].addr = priv->rx_ring[id].mapping[1]; - param.next = NULL; - param.wr_id = id | IPOIB_OP_RECV; - param.sg_list = &list; - param.num_sge = 1; - ret = ib_post_recv(priv->qp, ¶m, &bad_wr); + ret = ib_post_recv(priv->qp, &priv->rx_wr, &bad_wr); if (unlikely(ret)) { ipoib_warn(priv, "receive failed for buf %d (%d)\n", id, ret); - ib_dma_unmap_single(priv->ca, priv->rx_ring[id].mapping, - IPOIB_BUF_SIZE, DMA_FROM_DEVICE); + ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[id].mapping); dev_kfree_skb_any(priv->rx_ring[id].skb); priv->rx_ring[id].skb = NULL; } @@ -118,15 +149,21 @@ static int ipoib_ib_post_receive(struct net_device *dev, int id) return ret; } -static int ipoib_alloc_rx_skb(struct net_device *dev, int id) +static struct sk_buff *ipoib_alloc_rx_skb(struct net_device *dev, int id) { struct ipoib_dev_priv *priv = netdev_priv(dev); struct sk_buff *skb; - u64 addr; + int buf_size; + u64 *mapping; - skb = dev_alloc_skb(IPOIB_BUF_SIZE + 4); - if (!skb) - return -ENOMEM; + if (ipoib_ud_need_sg(priv->max_ib_mtu)) + buf_size = IPOIB_UD_HEAD_SIZE; + else + buf_size = IPOIB_UD_BUF_SIZE(priv->max_ib_mtu); + + skb = dev_alloc_skb(buf_size + 4); + if (unlikely(!skb)) + return NULL; /* * IB will leave a 40 byte gap for a GRH and IPoIB adds a 4 byte @@ -135,17 +172,32 @@ static int ipoib_alloc_rx_skb(struct net_device *dev, int id) */ skb_reserve(skb, 4); - addr = ib_dma_map_single(priv->ca, skb->data, IPOIB_BUF_SIZE, - DMA_FROM_DEVICE); - if (unlikely(ib_dma_mapping_error(priv->ca, addr))) { - dev_kfree_skb_any(skb); - return -EIO; + mapping = priv->rx_ring[id].mapping; + mapping[0] = ib_dma_map_single(priv->ca, skb->data, buf_size, + DMA_FROM_DEVICE); + if (unlikely(ib_dma_mapping_error(priv->ca, mapping[0]))) + goto error; + + if (ipoib_ud_need_sg(priv->max_ib_mtu)) { + struct page *page = alloc_page(GFP_ATOMIC); + if (!page) + goto partial_error; + skb_fill_page_desc(skb, 0, page, 0, PAGE_SIZE); + mapping[1] = + ib_dma_map_page(priv->ca, skb_shinfo(skb)->frags[0].page, + 0, PAGE_SIZE, DMA_FROM_DEVICE); + if (unlikely(ib_dma_mapping_error(priv->ca, mapping[1]))) + goto partial_error; } - priv->rx_ring[id].skb = skb; - priv->rx_ring[id].mapping = addr; + priv->rx_ring[id].skb = skb; + return skb; - return 0; +partial_error: + ib_dma_unmap_single(priv->ca, mapping[0], buf_size, DMA_FROM_DEVICE); +error: + dev_kfree_skb_any(skb); + return NULL; } static int ipoib_ib_post_receives(struct net_device *dev) @@ -154,7 +206,7 @@ static int ipoib_ib_post_receives(struct net_device *dev) int i; for (i = 0; i < ipoib_recvq_size; ++i) { - if (ipoib_alloc_rx_skb(dev, i)) { + if (!ipoib_alloc_rx_skb(dev, i)) { ipoib_warn(priv, "failed to allocate receive buffer %d\n", i); return -ENOMEM; } @@ -172,7 +224,7 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc) struct ipoib_dev_priv *priv = netdev_priv(dev); unsigned int wr_id = wc->wr_id & ~IPOIB_OP_RECV; struct sk_buff *skb; - u64 addr; + u64 mapping[IPOIB_UD_RX_SG]; ipoib_dbg_data(priv, "recv completion: id %d, status: %d\n", wr_id, wc->status); @@ -184,15 +236,13 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc) } skb = priv->rx_ring[wr_id].skb; - addr = priv->rx_ring[wr_id].mapping; if (unlikely(wc->status != IB_WC_SUCCESS)) { if (wc->status != IB_WC_WR_FLUSH_ERR) ipoib_warn(priv, "failed recv event " "(status=%d, wrid=%d vend_err %x)\n", wc->status, wr_id, wc->vendor_err); - ib_dma_unmap_single(priv->ca, addr, - IPOIB_BUF_SIZE, DMA_FROM_DEVICE); + ipoib_ud_dma_unmap_rx(priv, priv->rx_ring[wr_id].mapping); dev_kfree_skb_any(skb); priv->rx_ring[wr_id].skb = NULL; return; @@ -205,11 +255,14 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc) if (wc->slid == priv->local_lid && wc->src_qp == priv->qp->qp_num) goto repost; + memcpy(mapping, priv->rx_ring[wr_id].mapping, + IPOIB_UD_RX_SG * sizeof *mapping); + /* * If we can't allocate a new RX buffer, dump * this packet and reuse the old buffer. */ - if (unlikely(ipoib_alloc_rx_skb(dev, wr_id))) { + if (unlikely(!ipoib_alloc_rx_skb(dev, wr_id))) { ++dev->stats.rx_dropped; goto repost; } @@ -217,9 +270,9 @@ static void ipoib_ib_handle_rx_wc(struct net_device *dev, struct ib_wc *wc) ipoib_dbg_data(priv, "received %d bytes, SLID 0x%04x\n", wc->byte_len, wc->slid); - ib_dma_unmap_single(priv->ca, addr, IPOIB_BUF_SIZE, DMA_FROM_DEVICE); + ipoib_ud_dma_unmap_rx(priv, mapping); + ipoib_ud_skb_put_frags(priv, skb, wc->byte_len); - skb_put(skb, wc->byte_len); skb_pull(skb, IB_GRH_BYTES); skb->protocol = ((struct ipoib_header *) skb->data)->proto; @@ -733,10 +786,8 @@ int ipoib_ib_dev_stop(struct net_device *dev, int flush) rx_req = &priv->rx_ring[i]; if (!rx_req->skb) continue; - ib_dma_unmap_single(priv->ca, - rx_req->mapping, - IPOIB_BUF_SIZE, - DMA_FROM_DEVICE); + ipoib_ud_dma_unmap_rx(priv, + priv->rx_ring[i].mapping); dev_kfree_skb_any(rx_req->skb); rx_req->skb = NULL; } -- cgit v1.2.3