[PATCH net-next, v3] hyperv: Add handling of IP header with option field in netvsc_set_hash()

[Haiyang Zhang]

In case that the IP header has optional field at the end, this patch will
get the port numbers after that field, and compute the hash. The general
parser skb_flow_dissect() is used here.

Signed-off-by: Haiyang Zhang <***@microsoft.com>
Reviewed-by: K. Y. Srinivasan <***@microsoft.com>
---
drivers/net/hyperv/netvsc_drv.c | 26 ++++++++++----------------
1 files changed, 10 insertions(+), 16 deletions(-)

diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index 0fcb5e7..9e17d1a 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -162,7 +162,7 @@ union sub_key {
* data: network byte order
* return: host byte order
*/
-static u32 comp_hash(u8 *key, int klen, u8 *data, int dlen)
+static u32 comp_hash(u8 *key, int klen, void *data, int dlen)
{
union sub_key subk;
int k_next = 4;
@@ -176,7 +176,7 @@ static u32 comp_hash(u8 *key, int klen, u8 *data, int dlen)
for (i = 0; i < dlen; i++) {
subk.kb = key[k_next];
k_next = (k_next + 1) % klen;
- dt = data[i];
+ dt = ((u8 *)data)[i];
for (j = 0; j < 8; j++) {
if (dt & 0x80)
ret ^= subk.ka;
@@ -190,26 +190,20 @@ static u32 comp_hash(u8 *key, int klen, u8 *data, int dlen)

static bool netvsc_set_hash(u32 *hash, struct sk_buff *skb)
{
- struct iphdr *iphdr;
+ struct flow_keys flow;
int data_len;
- bool ret = false;

- if (eth_hdr(skb)->h_proto != htons(ETH_P_IP))
+ if (!skb_flow_dissect(skb, &flow) || flow.n_proto != htons(ETH_P_IP))
return false;

- iphdr = ip_hdr(skb);
+ if (flow.ip_proto == IPPROTO_TCP)
+ data_len = 12;
+ else
+ data_len = 8;

- if (iphdr->version == 4) {
- if (iphdr->protocol == IPPROTO_TCP)
- data_len = 12;
- else
- data_len = 8;
- *hash = comp_hash(netvsc_hash_key, HASH_KEYLEN,
- (u8 *)&iphdr->saddr, data_len);
- ret = true;
- }
+ *hash = comp_hash(netvsc_hash_key, HASH_KEYLEN, &flow, data_len);

- return ret;
+ return true;
}

static u16 netvsc_select_queue(struct net_device *ndev, struct sk_buff *skb,

[David Miller]

From: Haiyang Zhang <***@microsoft.com>
Date: Thu, 16 Oct 2014 14:47:58 -0700

Post by Haiyang Zhang
In case that the IP header has optional field at the end, this patch will
get the port numbers after that field, and compute the hash. The general
parser skb_flow_dissect() is used here.

Applied, thanks.