Attachment 880762 Details for Bug 1082266 – [PATCH] jme: Fix DMA unmap warning

[patch] [PATCH] jme: Fix DMA unmap warning

-jme-Fix-DMA-unmap-warning.patch (text/plain), 4.05 KB, created by Neil Horman on 2014-03-31 14:15:52 UTC

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Creator: Neil Horman

Created: 2014-03-31 14:15:52 UTC

Size: 4.05 KB

patch

obsolete

>From 7fd88c4ffd2ae90fe7a59d1319d7a5850029f8e5 Mon Sep 17 00:00:00 2001
>From: Neil Horman <nhorman@tuxdriver.com>
>Date: Mon, 31 Mar 2014 10:06:33 -0400
>Subject: [PATCH] jme: Fix DMA unmap warning
>
>The jme driver forgot to check the return status from pci_map_page in its tx
>path, causing a dma api warning on unmap.  Easy fix, just do the check and
>augment the tx path to tell the stack that the driver is busy so we re-queue the
>frame.
>
>Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
>CC: Guo-Fu Tseng <cooldavid@cooldavid.org>
>CC: "David S. Miller" <davem@davemloft.net>
>---
> drivers/net/ethernet/jme.c | 53 ++++++++++++++++++++++++++++++++++++++++------
> 1 file changed, 47 insertions(+), 6 deletions(-)
>
>diff --git a/drivers/net/ethernet/jme.c b/drivers/net/ethernet/jme.c
>index b0c6050..6e664d9 100644
>--- a/drivers/net/ethernet/jme.c
>+++ b/drivers/net/ethernet/jme.c
>@@ -1988,7 +1988,7 @@ jme_alloc_txdesc(struct jme_adapter *jme,
> 	return idx;
> }
> 
>-static void
>+static int
> jme_fill_tx_map(struct pci_dev *pdev,
> 		struct txdesc *txdesc,
> 		struct jme_buffer_info *txbi,
>@@ -2005,6 +2005,9 @@ jme_fill_tx_map(struct pci_dev *pdev,
> 				len,
> 				PCI_DMA_TODEVICE);
> 
>+	if (unlikely(pci_dma_mapping_error(pdev, dmaaddr)))
>+		return -EINVAL;
>+
> 	pci_dma_sync_single_for_device(pdev,
> 				       dmaaddr,
> 				       len,
>@@ -2021,9 +2024,30 @@ jme_fill_tx_map(struct pci_dev *pdev,
> 
> 	txbi->mapping = dmaaddr;
> 	txbi->len = len;
>+	return 0;
> }
> 
>-static void
>+static void jme_drop_tx_map(struct jme_adapter *jme, int startidx, int endidx)
>+{
>+	struct jme_ring *txring = &(jme->txring[0]);
>+	struct jme_buffer_info *txbi = txring->bufinf, *ctxbi;
>+	int mask = jme->tx_ring_mask;
>+	int j;
>+
>+	for (j = startidx ; j < endidx ; ++j) {
>+		ctxbi = txbi + ((startidx + j + 2) & (mask));
>+		pci_unmap_page(jme->pdev,
>+				ctxbi->mapping,
>+				ctxbi->len,
>+				PCI_DMA_TODEVICE);
>+
>+				ctxbi->mapping = 0;
>+				ctxbi->len = 0;
>+	}
>+
>+}
>+
>+static int
> jme_map_tx_skb(struct jme_adapter *jme, struct sk_buff *skb, int idx)
> {
> 	struct jme_ring *txring = &(jme->txring[0]);
>@@ -2034,25 +2058,37 @@ jme_map_tx_skb(struct jme_adapter *jme, struct sk_buff *skb, int idx)
> 	int mask = jme->tx_ring_mask;
> 	const struct skb_frag_struct *frag;
> 	u32 len;
>+	int ret = 0;
> 
> 	for (i = 0 ; i < nr_frags ; ++i) {
> 		frag = &skb_shinfo(skb)->frags[i];
> 		ctxdesc = txdesc + ((idx + i + 2) & (mask));
> 		ctxbi = txbi + ((idx + i + 2) & (mask));
> 
>-		jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi,
>+		ret = jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi,
> 				skb_frag_page(frag),
> 				frag->page_offset, skb_frag_size(frag), hidma);
>+		if (ret) {
>+			jme_drop_tx_map(jme, idx, idx+i);
>+			goto out;
>+		}
>+
> 	}
> 
> 	len = skb_is_nonlinear(skb) ? skb_headlen(skb) : skb->len;
> 	ctxdesc = txdesc + ((idx + 1) & (mask));
> 	ctxbi = txbi + ((idx + 1) & (mask));
>-	jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi, virt_to_page(skb->data),
>+	ret = jme_fill_tx_map(jme->pdev, ctxdesc, ctxbi, virt_to_page(skb->data),
> 			offset_in_page(skb->data), len, hidma);
>+	if (ret)
>+		jme_drop_tx_map(jme, idx, idx+i);
>+
>+out:
>+	return ret;
> 
> }
> 
>+
> static int
> jme_tx_tso(struct sk_buff *skb, __le16 *mss, u8 *flags)
> {
>@@ -2131,6 +2167,7 @@ jme_fill_tx_desc(struct jme_adapter *jme, struct sk_buff *skb, int idx)
> 	struct txdesc *txdesc;
> 	struct jme_buffer_info *txbi;
> 	u8 flags;
>+	int ret = 0;
> 
> 	txdesc = (struct txdesc *)txring->desc + idx;
> 	txbi = txring->bufinf + idx;
>@@ -2155,7 +2192,10 @@ jme_fill_tx_desc(struct jme_adapter *jme, struct sk_buff *skb, int idx)
> 	if (jme_tx_tso(skb, &txdesc->desc1.mss, &flags))
> 		jme_tx_csum(jme, skb, &flags);
> 	jme_tx_vlan(skb, &txdesc->desc1.vlan, &flags);
>-	jme_map_tx_skb(jme, skb, idx);
>+	ret = jme_map_tx_skb(jme, skb, idx);
>+	if (ret)
>+		return ret;
>+
> 	txdesc->desc1.flags = flags;
> 	/*
> 	 * Set tx buffer info after telling NIC to send
>@@ -2228,7 +2268,8 @@ jme_start_xmit(struct sk_buff *skb, struct net_device *netdev)
> 		return NETDEV_TX_BUSY;
> 	}
> 
>-	jme_fill_tx_desc(jme, skb, idx);
>+	if (jme_fill_tx_desc(jme, skb, idx))
>+		return NETDEV_TX_BUSY;
> 
> 	jwrite32(jme, JME_TXCS, jme->reg_txcs |
> 				TXCS_SELECT_QUEUE0 |
>-- 
>1.8.3.1
>

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Attachments on bug 1082266: 880229 | 880762