linux-kernel - [PATCH net-next 13/15] net: macb: drop `count` local variable in macb_tx

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20251014-macb-cleanup-v1-13-31cd266e22cd@bootlin.com>
Date: Tue, 14 Oct 2025 17:25:14 +0200
From: Théo Lebrun <theo.lebrun@...tlin.com>
To: Andrew Lunn <andrew+netdev@...n.ch>, 
 "David S. Miller" <davem@...emloft.net>, Eric Dumazet <edumazet@...gle.com>, 
 Jakub Kicinski <kuba@...nel.org>, Paolo Abeni <pabeni@...hat.com>, 
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>, 
 Nicolas Ferre <nicolas.ferre@...rochip.com>, 
 Claudiu Beznea <claudiu.beznea@...on.dev>, 
 Richard Cochran <richardcochran@...il.com>, 
 Russell King <linux@...linux.org.uk>
Cc: netdev@...r.kernel.org, devicetree@...r.kernel.org, 
 linux-kernel@...r.kernel.org, 
 Vladimir Kondratiev <vladimir.kondratiev@...ileye.com>, 
 Tawfik Bayouk <tawfik.bayouk@...ileye.com>, 
 Thomas Petazzoni <thomas.petazzoni@...tlin.com>, 
 Grégory Clement <gregory.clement@...tlin.com>, 
 Benoît Monin <benoit.monin@...tlin.com>, 
 Maxime Chevallier <maxime.chevallier@...tlin.com>, 
 Théo Lebrun <theo.lebrun@...tlin.com>
Subject: [PATCH net-next 13/15] net: macb: drop `count` local variable in
 macb_tx_map()

Local variable `count` is useless: it counts number of DMA descriptors
used and returns it. But the return value is only checked for error.
Drop counting the number of DMA descriptors and return a usual
negative-if-error integer.

Signed-off-by: Théo Lebrun <theo.lebrun@...tlin.com>
---
 drivers/net/ethernet/cadence/macb_main.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 08e541d8f8e68e38442a538ce352508c5db63f52..dd3b13fa304715b4629c20120a908262af106a2d 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -1992,7 +1992,7 @@ static unsigned int macb_tx_map(struct macb *bp,
 	unsigned int len, i, tx_head = queue->tx_head;
 	struct macb_tx_skb *tx_skb = NULL;
 	struct macb_dma_desc *desc;
-	unsigned int offset, size, count = 0;
+	unsigned int offset, size;
 	unsigned int f, nr_frags = skb_shinfo(skb)->nr_frags;
 	unsigned int eof = 1, mss_mfs = 0;
 	u32 ctrl, lso_ctrl = 0, seq_ctrl = 0;
@@ -2031,7 +2031,6 @@ static unsigned int macb_tx_map(struct macb *bp,

 		len -= size;
 		offset += size;
-		count++;
 		tx_head++;

 		size = umin(len, bp->max_tx_length);
@@ -2060,7 +2059,6 @@ static unsigned int macb_tx_map(struct macb *bp,

 			len -= size;
 			offset += size;
-			count++;
 			tx_head++;
 		}
 	}
@@ -2139,7 +2137,7 @@ static unsigned int macb_tx_map(struct macb *bp,

 	queue->tx_head = tx_head;

-	return count;
+	return 0;

 dma_error:
 	netdev_err(bp->dev, "TX DMA map failed\n");
@@ -2150,7 +2148,7 @@ static unsigned int macb_tx_map(struct macb *bp,
 		macb_tx_unmap(bp, tx_skb, 0);
 	}

-	return 0;
+	return -ENOMEM;
 }

 static netdev_features_t macb_features_check(struct sk_buff *skb,
@@ -2336,7 +2334,7 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	}

 	/* Map socket buffer for DMA transfer */
-	if (!macb_tx_map(bp, queue, skb, hdrlen)) {
+	if (macb_tx_map(bp, queue, skb, hdrlen)) {
 		dev_kfree_skb_any(skb);
 		goto unlock;
 	}

-- 
2.51.0