[PATCH] net: ethernet: mtk_eth_soc: use be32 type to store be32 values

[PATCH] net: ethernet: mtk_eth_soc: use be32 type to store be32 values

[Simon Horman]

Perhaps there is a nicer way to handle this but the code
calls for converting an array of host byte order 32bit values
to big endian 32bit values: an ipv6 address to be pretty printed.

Use a sparse-friendly array of be32 to store these values.

Also make use of the cpu_to_be32_array helper rather
than open coding the conversion.

Flagged by sparse:
  drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27: warning: incorrect type in assignment (different base types)
  drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27:    expected unsigned int
  drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27:    got restricted __be32 [usertype]
  drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:161:46: warning: cast to restricted __be16

No functional changes intended.
Compile tested only.

Signed-off-by: Simon Horman <horms@kernel.org>
---
 drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c b/drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c
index 53cf87e9acbb..1e0bb8cee7c4 100644
--- a/drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c
+++ b/drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c
@@ -47,16 +47,14 @@ static const char *mtk_foe_pkt_type_str(int type)
 static void
 mtk_print_addr(struct seq_file *m, u32 *addr, bool ipv6)
 {
-	u32 n_addr[4];
-	int i;
+	__be32 n_addr[4];
 
 	if (!ipv6) {
 		seq_printf(m, "%pI4h", addr);
 		return;
 	}
 
-	for (i = 0; i < ARRAY_SIZE(n_addr); i++)
-		n_addr[i] = htonl(addr[i]);
+	cpu_to_be32_array(n_addr, addr, 4);
 	seq_printf(m, "%pI6", n_addr);
 }
 

Re: [PATCH] net: ethernet: mtk_eth_soc: use be32 type to store be32 values

[Simon Horman]

On Sat, Apr 01, 2023 at 08:43:44AM +0200, Simon Horman wrote:
> Perhaps there is a nicer way to handle this but the code
> calls for converting an array of host byte order 32bit values
> to big endian 32bit values: an ipv6 address to be pretty printed.
> 
> Use a sparse-friendly array of be32 to store these values.
> 
> Also make use of the cpu_to_be32_array helper rather
> than open coding the conversion.
> 
> Flagged by sparse:
>   drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27: warning: incorrect type in assignment (different base types)
>   drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27:    expected unsigned int
>   drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:59:27:    got restricted __be32 [usertype]
>   drivers/net/ethernet/mediatek/mtk_ppe_debugfs.c:161:46: warning: cast to restricted __be16
> 
> No functional changes intended.
> Compile tested only.
> 
> Signed-off-by: Simon Horman <horms@kernel.org>

Sorry, I forgot to tag this for net-next.
I can repost if needed, after an appropriate pause.

Re: [PATCH] net: ethernet: mtk_eth_soc: use be32 type to store be32 values

[Andrew Lunn]

On Sat, Apr 01, 2023 at 08:43:44AM +0200, Simon Horman wrote:
> Perhaps there is a nicer way to handle this but the code
> calls for converting an array of host byte order 32bit values
> to big endian 32bit values: an ipv6 address to be pretty printed.

Hi Simon

Maybe make a generic helper? I could be used in other places, e.g:

https://elixir.bootlin.com/linux/latest/source/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c#L6773

	Andrew

Re: [PATCH] net: ethernet: mtk_eth_soc: use be32 type to store be32 values

[Simon Horman]

On Sat, Apr 01, 2023 at 05:55:35PM +0200, Andrew Lunn wrote:
> On Sat, Apr 01, 2023 at 08:43:44AM +0200, Simon Horman wrote:
> > Perhaps there is a nicer way to handle this but the code
> > calls for converting an array of host byte order 32bit values
> > to big endian 32bit values: an ipv6 address to be pretty printed.
> 
> Hi Simon
> 
> Maybe make a generic helper? I could be used in other places, e.g:
> 
> https://elixir.bootlin.com/linux/latest/source/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_main.c#L6773

Hi Andrew,

do you mean something like this?

diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 7332296eca44..cff6c1177502 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -935,6 +935,11 @@ static inline void iph_to_flow_copy_v6addrs(struct flow_keys *flow,
 	flow->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
 }
 
+static inline void ipv6_addr_cpu_to_be32(__be32 *dst, const u32 *src)
+{
+	cpu_to_be32_array(dst, src, 4);
+}
+
 #if IS_ENABLED(CONFIG_IPV6)
 
 static inline bool ipv6_can_nonlocal_bind(struct net *net,