Merge the combo uses of cpu_to_le32s and memcpy.
Use put_unaligned_le32 instead.
This simplifies the code.
Signed-off-by: Chuhong Yuan <[email protected]>
---
drivers/net/usb/asix_common.c | 9 ++++-----
drivers/net/usb/ax88179_178a.c | 11 ++++-------
drivers/net/usb/lan78xx.c | 11 ++++-------
drivers/net/usb/smsc75xx.c | 11 ++++-------
drivers/net/usb/sr9800.c | 9 ++++-----
5 files changed, 20 insertions(+), 31 deletions(-)
diff --git a/drivers/net/usb/asix_common.c b/drivers/net/usb/asix_common.c
index b39ee714fb01..e39f41efda3e 100644
--- a/drivers/net/usb/asix_common.c
+++ b/drivers/net/usb/asix_common.c
@@ -221,6 +221,7 @@ struct sk_buff *asix_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
int tailroom = skb_tailroom(skb);
u32 packet_len;
u32 padbytes = 0xffff0000;
+ void *ptr;
padlen = ((skb->len + 4) & (dev->maxpacket - 1)) ? 0 : 4;
@@ -256,13 +257,11 @@ struct sk_buff *asix_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
}
packet_len = ((skb->len ^ 0x0000ffff) << 16) + skb->len;
- skb_push(skb, 4);
- cpu_to_le32s(&packet_len);
- skb_copy_to_linear_data(skb, &packet_len, sizeof(packet_len));
+ ptr = skb_push(skb, 4);
+ put_unaligned_le32(packet_len, ptr);
if (padlen) {
- cpu_to_le32s(&padbytes);
- memcpy(skb_tail_pointer(skb), &padbytes, sizeof(padbytes));
+ put_unaligned_le32(padbytes, skb_tail_pointer(skb));
skb_put(skb, sizeof(padbytes));
}
diff --git a/drivers/net/usb/ax88179_178a.c b/drivers/net/usb/ax88179_178a.c
index 72d165114b67..daa54486ab09 100644
--- a/drivers/net/usb/ax88179_178a.c
+++ b/drivers/net/usb/ax88179_178a.c
@@ -1421,6 +1421,7 @@ ax88179_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
int frame_size = dev->maxpacket;
int mss = skb_shinfo(skb)->gso_size;
int headroom;
+ void *ptr;
tx_hdr1 = skb->len;
tx_hdr2 = mss;
@@ -1435,13 +1436,9 @@ ax88179_tx_fixup(struct usbnet *dev, struct sk_buff *skb, gfp_t flags)
return NULL;
}
- skb_push(skb, 4);
- cpu_to_le32s(&tx_hdr2);
- skb_copy_to_linear_data(skb, &tx_hdr2, 4);
-
- skb_push(skb, 4);
- cpu_to_le32s(&tx_hdr1);
- skb_copy_to_linear_data(skb, &tx_hdr1, 4);
+ ptr = skb_push(skb, 8);
+ put_unaligned_le32(tx_hdr1, ptr);
+ put_unaligned_le32(tx_hdr2, ptr + 4);
return skb;
}
diff --git a/drivers/net/usb/lan78xx.c b/drivers/net/usb/lan78xx.c
index 9c33b35bd155..769bb262fbec 100644
--- a/drivers/net/usb/lan78xx.c
+++ b/drivers/net/usb/lan78xx.c
@@ -2729,6 +2729,7 @@ static struct sk_buff *lan78xx_tx_prep(struct lan78xx_net *dev,
struct sk_buff *skb, gfp_t flags)
{
u32 tx_cmd_a, tx_cmd_b;
+ void *ptr;
if (skb_cow_head(skb, TX_OVERHEAD)) {
dev_kfree_skb_any(skb);
@@ -2757,13 +2758,9 @@ static struct sk_buff *lan78xx_tx_prep(struct lan78xx_net *dev,
tx_cmd_b |= skb_vlan_tag_get(skb) & TX_CMD_B_VTAG_MASK_;
}
- skb_push(skb, 4);
- cpu_to_le32s(&tx_cmd_b);
- memcpy(skb->data, &tx_cmd_b, 4);
-
- skb_push(skb, 4);
- cpu_to_le32s(&tx_cmd_a);
- memcpy(skb->data, &tx_cmd_a, 4);
+ ptr = skb_push(skb, 8);
+ put_unaligned_le32(tx_cmd_a, ptr);
+ put_unaligned_le32(tx_cmd_b, ptr + 4);
return skb;
}
diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 7fac9db5380d..9556d431885f 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c
@@ -2255,6 +2255,7 @@ static struct sk_buff *smsc75xx_tx_fixup(struct usbnet *dev,
struct sk_buff *skb, gfp_t flags)
{
u32 tx_cmd_a, tx_cmd_b;
+ void *ptr;
if (skb_cow_head(skb, SMSC75XX_TX_OVERHEAD)) {
dev_kfree_skb_any(skb);
@@ -2275,13 +2276,9 @@ static struct sk_buff *smsc75xx_tx_fixup(struct usbnet *dev,
tx_cmd_b = 0;
}
- skb_push(skb, 4);
- cpu_to_le32s(&tx_cmd_b);
- memcpy(skb->data, &tx_cmd_b, 4);
-
- skb_push(skb, 4);
- cpu_to_le32s(&tx_cmd_a);
- memcpy(skb->data, &tx_cmd_a, 4);
+ ptr = skb_push(skb, 8);
+ put_unaligned_le32(tx_cmd_a, ptr);
+ put_unaligned_le32(tx_cmd_b, ptr + 4);
return skb;
}
diff --git a/drivers/net/usb/sr9800.c b/drivers/net/usb/sr9800.c
index 35f39f23d881..c5d4a0060124 100644
--- a/drivers/net/usb/sr9800.c
+++ b/drivers/net/usb/sr9800.c
@@ -115,6 +115,7 @@ static struct sk_buff *sr_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
u32 padbytes = 0xffff0000;
u32 packet_len;
int padlen;
+ void *ptr;
padlen = ((skb->len + 4) % (dev->maxpacket - 1)) ? 0 : 4;
@@ -133,14 +134,12 @@ static struct sk_buff *sr_tx_fixup(struct usbnet *dev, struct sk_buff *skb,
return NULL;
}
- skb_push(skb, 4);
+ ptr = skb_push(skb, 4);
packet_len = (((skb->len - 4) ^ 0x0000ffff) << 16) + (skb->len - 4);
- cpu_to_le32s(&packet_len);
- skb_copy_to_linear_data(skb, &packet_len, sizeof(packet_len));
+ put_unaligned_le32(packet_len, ptr);
if (padlen) {
- cpu_to_le32s(&padbytes);
- memcpy(skb_tail_pointer(skb), &padbytes, sizeof(padbytes));
+ put_unaligned_le32(padbytes, skb_tail_pointer(skb));
skb_put(skb, sizeof(padbytes));
}
--
2.20.1
David Miller <[email protected]> 于2019年7月23日周二 上午9:22写道：
>
> From: Chuhong Yuan <[email protected]>
> Date: Mon, 22 Jul 2019 15:41:34 +0800
>
> > Merge the combo uses of cpu_to_le32s and memcpy.
> > Use put_unaligned_le32 instead.
> > This simplifies the code.
> >
> > Signed-off-by: Chuhong Yuan <[email protected]>
>
> Isn't the skb->data aligned to 4 bytes in these situations?
>
> If so, we should use the aligned variants.
>
> Thank you.
I have checked the five changed files.
I find that they all have used get_unaligned_le32 for skb->data
according to my previous applied patches and existing code.
So I think the skb->data is unaligned in these situations.
Usages of get_unaligned_le32:
asix_common.c: line 104 and 133
ax88179_178a.c: https://lkml.org/lkml/2019/7/19/652
lan78xx.c: https://lkml.org/lkml/2019/7/19/573
smsc75xx.c: https://lkml.org/lkml/2019/7/19/617
sr9800.c: line 73
From: Chuhong Yuan <[email protected]>
Date: Tue, 23 Jul 2019 10:16:27 +0800
> David Miller <[email protected]> $BP2(B2019$BG/(B7$B7n(B23$BF|<~Fs(B $B>e8a(B9:22$B<LF;!'(B
>>
>> From: Chuhong Yuan <[email protected]>
>> Date: Mon, 22 Jul 2019 15:41:34 +0800
>>
>> > Merge the combo uses of cpu_to_le32s and memcpy.
>> > Use put_unaligned_le32 instead.
>> > This simplifies the code.
>> >
>> > Signed-off-by: Chuhong Yuan <[email protected]>
>>
>> Isn't the skb->data aligned to 4 bytes in these situations?
>>
>> If so, we should use the aligned variants.
>>
>> Thank you.
>
> I have checked the five changed files.
> I find that they all have used get_unaligned_le32 for skb->data
> according to my previous applied patches and existing code.
> So I think the skb->data is unaligned in these situations.
Thank you for checking.
Patch applied to net-next.
From: Chuhong Yuan <[email protected]>
Date: Mon, 22 Jul 2019 15:41:34 +0800
> Merge the combo uses of cpu_to_le32s and memcpy.
> Use put_unaligned_le32 instead.
> This simplifies the code.
>
> Signed-off-by: Chuhong Yuan <[email protected]>
Isn't the skb->data aligned to 4 bytes in these situations?
If so, we should use the aligned variants.
Thank you.