[PATCH net-next 0/2] net: Use helper function IS_ERR_OR_NULL()

[PATCH net-next 0/2] net: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

Use IS_ERR_OR_NULL() instead of open-coding it
to simplify the code.

Ruan Jinjie (2):
  net: microchip: sparx5: Use helper function IS_ERR_OR_NULL()
  net: stmmac: Use helper function IS_ERR_OR_NULL()

 drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c | 2 +-
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c        | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

-- 
2.34.1

[PATCH net-next 1/2] net: microchip: sparx5: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

Use IS_ERR_OR_NULL() instead of open-coding it
to simplify the code.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
---
 drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
index 906299ad8425..bc1b4498ed04 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c
@@ -1274,7 +1274,7 @@ static int sparx5_tc_free_rule_resources(struct net_device *ndev,
 	int ret = 0;
 
 	vrule = vcap_get_rule(vctrl, rule_id);
-	if (!vrule || IS_ERR(vrule))
+	if (IS_ERR_OR_NULL(vrule))
 		return -EINVAL;
 
 	sparx5_tc_free_psfp_resources(sparx5, vrule);
-- 
2.34.1

[PATCH net-next 2/2] net: stmmac: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

Use IS_ERR_OR_NULL() instead of open-coding it
to simplify the code.

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 733b5e900817..fe2452a70d23 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1165,7 +1165,7 @@ static int stmmac_init_phy(struct net_device *dev)
 	/* Some DT bindings do not set-up the PHY handle. Let's try to
 	 * manually parse it
 	 */
-	if (!phy_fwnode || IS_ERR(phy_fwnode)) {
+	if (IS_ERR_OR_NULL(phy_fwnode)) {
 		int addr = priv->plat->phy_addr;
 		struct phy_device *phydev;
 
-- 
2.34.1

Re: [PATCH net-next 2/2] net: stmmac: Use helper function IS_ERR_OR_NULL()

[Russell King (Oracle)]

On Thu, Aug 17, 2023 at 03:19:41PM +0800, Ruan Jinjie wrote:
> Use IS_ERR_OR_NULL() instead of open-coding it
> to simplify the code.
> 
> Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
> ---
>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> index 733b5e900817..fe2452a70d23 100644
> --- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> +++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
> @@ -1165,7 +1165,7 @@ static int stmmac_init_phy(struct net_device *dev)
>  	/* Some DT bindings do not set-up the PHY handle. Let's try to
>  	 * manually parse it
>  	 */
> -	if (!phy_fwnode || IS_ERR(phy_fwnode)) {
> +	if (IS_ERR_OR_NULL(phy_fwnode)) {
>  		int addr = priv->plat->phy_addr;
>  		struct phy_device *phydev;

Up to the stmmac maintainers, but I have never been a fan of
"IS_ERR_OR_NULL" because it leads to programming errors such as
those I pointed out in your changes to I2C drivers. I would
much rather see IS_ERR_OR_NULL removed from the kernel entirely.
That is my personal opinion.

In this case, it doesn't matter because we're not returning the
phy_fwnode error, we're detecting it and taking some alternative
action - but given my inherent dislike of IS_ERR_OR_NULL, I
prefer the original.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 0/2] net: Use helper function IS_ERR_OR_NULL()

[Leon Romanovsky]

On Thu, Aug 17, 2023 at 03:19:39PM +0800, Ruan Jinjie wrote:
> Use IS_ERR_OR_NULL() instead of open-coding it
> to simplify the code.
> 
> Ruan Jinjie (2):
>   net: microchip: sparx5: Use helper function IS_ERR_OR_NULL()
>   net: stmmac: Use helper function IS_ERR_OR_NULL()
> 
>  drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c | 2 +-
>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c        | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 

Thanks,
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>

As a side note, grep of vcap_get_rule() shows that many callers don't
properly check return value and expect it to be or valid or NULL.

For example this code is not correct:
drivers/net/ethernet/microchip/lan966x/lan966x_ptp.c
    61         vrule = vcap_get_rule(lan966x->vcap_ctrl, rule_id);
    62         if (vrule) {
    63                 u32 value, mask;
    64
    65                 /* Just modify the ingress port mask and exit */
    66                 vcap_rule_get_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
    67                                       &value, &mask);
    68                 mask &= ~BIT(port->chip_port);
    69                 vcap_rule_mod_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
    70                                       value, mask);
    71
    72                 err = vcap_mod_rule(vrule);
    73                 goto free_rule;
    74         }

Re: [PATCH net-next 0/2] net: Use helper function IS_ERR_OR_NULL()

[Ruan Jinjie]

On 2023/8/17 16:02, Leon Romanovsky wrote:
> On Thu, Aug 17, 2023 at 03:19:39PM +0800, Ruan Jinjie wrote:
>> Use IS_ERR_OR_NULL() instead of open-coding it
>> to simplify the code.
>>
>> Ruan Jinjie (2):
>>   net: microchip: sparx5: Use helper function IS_ERR_OR_NULL()
>>   net: stmmac: Use helper function IS_ERR_OR_NULL()
>>
>>  drivers/net/ethernet/microchip/sparx5/sparx5_tc_flower.c | 2 +-
>>  drivers/net/ethernet/stmicro/stmmac/stmmac_main.c        | 2 +-
>>  2 files changed, 2 insertions(+), 2 deletions(-)
>>
> 
> Thanks,
> Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
> 
> As a side note, grep of vcap_get_rule() shows that many callers don't
> properly check return value and expect it to be or valid or NULL.

Right! I will try to fix these problems together by the way. Thank you!

> 
> For example this code is not correct:
> drivers/net/ethernet/microchip/lan966x/lan966x_ptp.c
>     61         vrule = vcap_get_rule(lan966x->vcap_ctrl, rule_id);
>     62         if (vrule) {
>     63                 u32 value, mask;
>     64
>     65                 /* Just modify the ingress port mask and exit */
>     66                 vcap_rule_get_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
>     67                                       &value, &mask);
>     68                 mask &= ~BIT(port->chip_port);
>     69                 vcap_rule_mod_key_u32(vrule, VCAP_KF_IF_IGR_PORT_MASK,
>     70                                       value, mask);
>     71
>     72                 err = vcap_mod_rule(vrule);
>     73                 goto free_rule;
>     74         }
>