[PATCH 3.19.y-ckt 126/146] staging: vt6655: vnt_tx_packet fix dma_idx selection.

From: Kamal Mostafa
Date: Wed Jun 17 2015 - 19:07:45 EST


3.19.8-ckt2 -stable review patch. If anyone has any objections, please let me know.

------------------

From: Malcolm Priestley <tvboxspy@xxxxxxxxx>

commit c312530589ed9524fc7cc921105dc9b67ea32d6a upstream.

There is still a problem that dma_idx is causing packets to
go onto the wrong tx path.

Protect dma_idx fully with the present first lock and
use pTDInfo->byFlags TD_FLAGS_NETIF_SKB to set MACvTransmit.

Signed-off-by: Malcolm Priestley <tvboxspy@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/staging/vt6655/device_main.c | 16 +++++++++-------
1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c
index 4d29c05..7d9f563 100644
--- a/drivers/staging/vt6655/device_main.c
+++ b/drivers/staging/vt6655/device_main.c
@@ -1205,12 +1205,14 @@ static int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb)
{
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
PSTxDesc head_td;
- u32 dma_idx = TYPE_AC0DMA;
+ u32 dma_idx;
unsigned long flags;

spin_lock_irqsave(&priv->lock, flags);

- if (!ieee80211_is_data(hdr->frame_control))
+ if (ieee80211_is_data(hdr->frame_control))
+ dma_idx = TYPE_AC0DMA;
+ else
dma_idx = TYPE_TXDMA0;

if (AVAIL_TD(priv, dma_idx) < 1) {
@@ -1224,6 +1226,9 @@ static int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb)

head_td->pTDInfo->skb = skb;

+ if (dma_idx == TYPE_AC0DMA)
+ head_td->pTDInfo->byFlags = TD_FLAGS_NETIF_SKB;
+
priv->iTDUsed[dma_idx]++;

/* Take ownership */
@@ -1252,13 +1257,10 @@ static int vnt_tx_packet(struct vnt_private *priv, struct sk_buff *skb)

head_td->buff_addr = cpu_to_le32(head_td->pTDInfo->skb_dma);

- if (dma_idx == TYPE_AC0DMA) {
- head_td->pTDInfo->byFlags = TD_FLAGS_NETIF_SKB;
-
+ if (head_td->pTDInfo->byFlags & TD_FLAGS_NETIF_SKB)
MACvTransmitAC0(priv->PortOffset);
- } else {
+ else
MACvTransmit0(priv->PortOffset);
- }

spin_unlock_irqrestore(&priv->lock, flags);

--
1.9.1

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