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From: Marc Kleine-Budde <mkl@pengutronix.de>
To: linux-can@vger.kernel.org
Cc: kernel@pengutronix.de, Marc Kleine-Budde <mkl@pengutronix.de>
Subject: [PATCH 11/37] can: dev: can_put_echo_skb(): propagate error in case of errors
Date: Wed, 16 Sep 2020 00:35:01 +0200
Message-ID: <20200915223527.1417033-12-mkl@pengutronix.de> (raw)
In-Reply-To: <20200915223527.1417033-1-mkl@pengutronix.de>

The function can_put_echo_skb() can fail for several reasons. It may
fail due to OOM, but when it fails it's usually due to locking problems
in the driver.

In order to help developing and debugging of new drivers propagate error
value in case of errors.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 drivers/net/can/dev.c   | 11 +++++++----
 include/linux/can/dev.h |  4 ++--
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/net/can/dev.c b/drivers/net/can/dev.c
index dd443e5d8cb7..77a5663693af 100644
--- a/drivers/net/can/dev.c
+++ b/drivers/net/can/dev.c
@@ -434,8 +434,8 @@ static void can_flush_echo_skb(struct net_device *dev)
  * of the device driver. The driver must protect access to
  * priv->echo_skb, if necessary.
  */
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
-		      unsigned int idx)
+int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+		     unsigned int idx)
 {
 	struct can_priv *priv = netdev_priv(dev);
 
@@ -446,13 +446,13 @@ void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 	    (skb->protocol != htons(ETH_P_CAN) &&
 	     skb->protocol != htons(ETH_P_CANFD))) {
 		kfree_skb(skb);
-		return;
+		return 0;
 	}
 
 	if (!priv->echo_skb[idx]) {
 		skb = can_create_echo_skb(skb);
 		if (!skb)
-			return;
+			return -ENOMEM;
 
 		/* make settings for echo to reduce code in irq context */
 		skb->pkt_type = PACKET_BROADCAST;
@@ -465,7 +465,10 @@ void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
 		/* locking problem with netif_stop_queue() ?? */
 		netdev_err(dev, "%s: BUG! echo_skb %d is occupied!\n", __func__, idx);
 		kfree_skb(skb);
+		return -EBUSY;
 	}
+
+	return 0;
 }
 EXPORT_SYMBOL_GPL(can_put_echo_skb);
 
diff --git a/include/linux/can/dev.h b/include/linux/can/dev.h
index 516892566ac9..ed0482b2f4b2 100644
--- a/include/linux/can/dev.h
+++ b/include/linux/can/dev.h
@@ -201,8 +201,8 @@ void can_bus_off(struct net_device *dev);
 void can_change_state(struct net_device *dev, struct can_frame *cf,
 		      enum can_state tx_state, enum can_state rx_state);
 
-void can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
-		      unsigned int idx);
+int can_put_echo_skb(struct sk_buff *skb, struct net_device *dev,
+		     unsigned int idx);
 struct sk_buff *__can_get_echo_skb(struct net_device *dev, unsigned int idx,
 				   u8 *len_ptr);
 unsigned int can_get_echo_skb(struct net_device *dev, unsigned int idx);
-- 
2.28.0


  parent reply index

Thread overview: 38+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-09-15 22:34 [RFC]: can-next 2020-09-16 Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 01/37] can: grcan: fix spelling mistake "buss" -> "bus" Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 02/37] can: flexcan: fix spelling mistake "reserverd" -> "reserved" Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 03/37] can: include: fix spelling mistakes Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 04/37] can: net: " Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 05/37] can: drivers: " Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 06/37] can: raw: fix indention Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 07/37] can: slcan: update dead link Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 08/37] can: softing: " Marc Kleine-Budde
2020-09-15 22:34 ` [PATCH 09/37] can: remove "WITH Linux-syscall-note" from SPDX tag of C files Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 10/37] can: dev: can_put_echo_skb(): print number of echo_skb that is occupied Marc Kleine-Budde
2020-09-15 22:35 ` Marc Kleine-Budde [this message]
2020-09-15 22:35 ` [PATCH 12/37] can: dev: can_change_state(): print human readable state change messages Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 13/37] can: dev: can_bus_off(): print scheduling of restart if activated Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 14/37] can: c_can: Remove unused inline function Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 15/37] can: mcba_usb: remove redundant initialization of variable err Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 16/37] can: mscan: mark expected switch fall-through Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 17/37] can: ti_hecc: convert to devm_platform_ioremap_resource_byname() Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 18/37] can: peak_usb: convert to use le32_add_cpu() Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 19/37] can: peak_canfd: Remove unused macros Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 20/37] can: pch_can: use generic power management Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 21/37] can: pcan_usb: Document the commands sent to the device Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 22/37] can: pcan_usb: add support of rxerr/txerr counters Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 23/37] can: spi: Kconfig: remove unneeded dependencies form Kconfig symbols Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 24/37] dt-bindings: can: mcp251x: change example interrupt type to IRQ_TYPE_LEVEL_LOW Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 25/37] dt-bindings: can: mcp251x: document GPIO support Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 26/37] can: mcp251x: sort include files alphabetically Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 27/37] can: mcp251x: add GPIO support Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 28/37] can: mcp251x: Use readx_poll_timeout() helper Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 29/37] can: mcp251x: add support for half duplex controllers Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 30/37] can: mscan: mpc5xxx_can: update contact email Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 31/37] can: mscan: simplify clock enable/disable Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 32/37] can: rx-offload: can_rx_offload_add_manual(): add new initialization function Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 33/37] dt-binding: can: mcp25xxfd: document device tree bindings Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 34/37] can: mcp25xxfd: add regmap infrastructure Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 35/37] can: mcp25xxfd: add driver for Microchip MCP25xxFD SPI CAN Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 36/37] can: mcp25xxfd: add listen-only mode Marc Kleine-Budde
2020-09-15 22:35 ` [PATCH 37/37] MAINTAINERS: Add entry for Microchip MCP25XXFD SPI-CAN network driver Marc Kleine-Budde

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