[PATCH net-next] net: caif: fix return type of ndo_start_xmit function

[PATCH net-next] net: caif: fix return type of ndo_start_xmit function

[YueHaibing]

The method ndo_start_xmit() is defined as returning an 'netdev_tx_t',
which is a typedef for an enum type, so make sure the implementation in
this driver has returns 'netdev_tx_t' value, and change the function
return type to netdev_tx_t.

Found by coccinelle.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
---
 drivers/net/caif/caif_hsi.c    | 10 +++++-----
 drivers/net/caif/caif_serial.c |  7 +++++--
 drivers/net/caif/caif_spi.c    |  6 +++---
 drivers/net/caif/caif_virtio.c |  2 +-
 net/caif/chnl_net.c            |  3 ++-
 5 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/drivers/net/caif/caif_hsi.c b/drivers/net/caif/caif_hsi.c
index 433a14b..70c449e 100644
--- a/drivers/net/caif/caif_hsi.c
+++ b/drivers/net/caif/caif_hsi.c
@@ -1006,7 +1006,7 @@ static void cfhsi_aggregation_tout(struct timer_list *t)
 	cfhsi_start_tx(cfhsi);
 }
 
-static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct cfhsi *cfhsi = NULL;
 	int start_xfer = 0;
@@ -1014,7 +1014,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
 	int prio;
 
 	if (!dev)
-		return -EINVAL;
+		return NETDEV_TX_BUSY;
 
 	cfhsi = netdev_priv(dev);
 
@@ -1048,7 +1048,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
 	if (WARN_ON(test_bit(CFHSI_SHUTDOWN, &cfhsi->bits))) {
 		spin_unlock_bh(&cfhsi->lock);
 		cfhsi_abort_tx(cfhsi);
-		return -EINVAL;
+		return NETDEV_TX_BUSY;
 	}
 
 	/* Send flow off if number of packets is above high water mark. */
@@ -1072,7 +1072,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
 		spin_unlock_bh(&cfhsi->lock);
 		if (aggregate_ready)
 			cfhsi_start_tx(cfhsi);
-		return 0;
+		return NETDEV_TX_OK;
 	}
 
 	/* Delete inactivity timer if started. */
@@ -1102,7 +1102,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
 			queue_work(cfhsi->wq, &cfhsi->wake_up_work);
 	}
 
-	return 0;
+	return NETDEV_TX_OK;
 }
 
 static const struct net_device_ops cfhsi_netdevops;
diff --git a/drivers/net/caif/caif_serial.c b/drivers/net/caif/caif_serial.c
index a0f954f..acb3264 100644
--- a/drivers/net/caif/caif_serial.c
+++ b/drivers/net/caif/caif_serial.c
@@ -275,7 +275,7 @@ static int handle_tx(struct ser_device *ser)
 	return tty_wr;
 }
 
-static int caif_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t caif_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ser_device *ser;
 
@@ -290,7 +290,10 @@ static int caif_xmit(struct sk_buff *skb, struct net_device *dev)
 		ser->common.flowctrl(ser->dev, OFF);
 
 	skb_queue_tail(&ser->head, skb);
-	return handle_tx(ser);
+	if (handle_tx(ser))
+		return NETDEV_TX_BUSY;
+
+	return NETDEV_TX_OK;
 }
 
 
diff --git a/drivers/net/caif/caif_spi.c b/drivers/net/caif/caif_spi.c
index d28a139..9040658 100644
--- a/drivers/net/caif/caif_spi.c
+++ b/drivers/net/caif/caif_spi.c
@@ -486,12 +486,12 @@ static void cfspi_xfer_done_cb(struct cfspi_ifc *ifc)
 	complete(&cfspi->comp);
 }
 
-static int cfspi_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t cfspi_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct cfspi *cfspi = NULL;
 	unsigned long flags;
 	if (!dev)
-		return -EINVAL;
+		return NETDEV_TX_BUSY;
 
 	cfspi = netdev_priv(dev);
 
@@ -512,7 +512,7 @@ static int cfspi_xmit(struct sk_buff *skb, struct net_device *dev)
 		cfspi->cfdev.flowctrl(cfspi->ndev, 0);
 	}
 
-	return 0;
+	return NETDEV_TX_OK;
 }
 
 int cfspi_rxfrm(struct cfspi *cfspi, u8 *buf, size_t len)
diff --git a/drivers/net/caif/caif_virtio.c b/drivers/net/caif/caif_virtio.c
index 2814e0d..f5507db 100644
--- a/drivers/net/caif/caif_virtio.c
+++ b/drivers/net/caif/caif_virtio.c
@@ -519,7 +519,7 @@ static struct buf_info *cfv_alloc_and_copy_to_shm(struct cfv_info *cfv,
 }
 
 /* Put the CAIF packet on the virtio ring and kick the receiver */
-static int cfv_netdev_tx(struct sk_buff *skb, struct net_device *netdev)
+static netdev_tx_t cfv_netdev_tx(struct sk_buff *skb, struct net_device *netdev)
 {
 	struct cfv_info *cfv = netdev_priv(netdev);
 	struct buf_info *buf_info;
diff --git a/net/caif/chnl_net.c b/net/caif/chnl_net.c
index 13e2ae6..30be426 100644
--- a/net/caif/chnl_net.c
+++ b/net/caif/chnl_net.c
@@ -211,7 +211,8 @@ static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow,
 	}
 }
 
-static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
+static netdev_tx_t
+chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct chnl_net *priv;
 	struct cfpkt *pkt = NULL;
-- 
1.8.3.1

Re: [PATCH net-next] net: caif: fix return type of ndo_start_xmit function

[David Miller]

From: YueHaibing <yuehaibing@huawei.com>
Date: Wed, 26 Sep 2018 17:27:05 +0800

> @@ -1014,7 +1014,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
>  	int prio;
>  
>  	if (!dev)
> -		return -EINVAL;
> +		return NETDEV_TX_BUSY;
>  
>  	cfhsi = netdev_priv(dev);
>  

Even though the return type of ndo_start_xmit is netdev_tx_t, negative error codes are
still allowed I believe.

Look, reviewing these are pretty stressful for me, because you aren't documenting your
changes and in many cases the transformations look incorrect.

I'm tossing the rest of your changes in this area for now, sorry.

Please double check your work and resubmit this at some time in the not-too-near
future.

Thank you.

Re: [PATCH net-next] net: caif: fix return type of ndo_start_xmit function

[YueHaibing]

On 2018/9/30 2:38, David Miller wrote:
> From: YueHaibing <yuehaibing@huawei.com>
> Date: Wed, 26 Sep 2018 17:27:05 +0800
> 
>> @@ -1014,7 +1014,7 @@ static int cfhsi_xmit(struct sk_buff *skb, struct net_device *dev)
>>  	int prio;
>>  
>>  	if (!dev)
>> -		return -EINVAL;
>> +		return NETDEV_TX_BUSY;
>>  
>>  	cfhsi = netdev_priv(dev);
>>  
> 
> Even though the return type of ndo_start_xmit is netdev_tx_t, negative error codes are
> still allowed I believe.

I missed this and do the wrong thing.

> 
> Look, reviewing these are pretty stressful for me, because you aren't documenting your
> changes and in many cases the transformations look incorrect.
> 

I'm really sorry for this.

> I'm tossing the rest of your changes in this area for now, sorry.
> 
> Please double check your work and resubmit this at some time in the not-too-near
> future.
> 
> Thank you.
> 
> .
>