[PATCH net-next] liquidio: store the L4 hash of rx packets in skb

From: Prasad Kanneganti <redacted>

Store the L4 hash of received packets in the skb; the hash is computed in
the NIC firmware.

Signed-off-by: Prasad Kanneganti <redacted>
Signed-off-by: Felix Manlunas <redacted>
Signed-off-by: Derek Chickles <redacted>
Signed-off-by: Satanand Burla <redacted>
---
 drivers/net/ethernet/cavium/liquidio/lio_main.c        | 17 +++++++++++++++--
 drivers/net/ethernet/cavium/liquidio/lio_vf_main.c     | 15 ++++++++++++++-
 drivers/net/ethernet/cavium/liquidio/liquidio_common.h |  2 ++
 3 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_main.c b/drivers/net/ethernet/cavium/liquidio/lio_main.c
index 39a9665..adae858 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_main.c

@@ -2263,6 +2263,7 @@ liquidio_push_packet(u32 octeon_id __attribute__((unused)),
 	struct skb_shared_hwtstamps *shhwtstamps;
 	u64 ns;
 	u16 vtag = 0;
+	u32 r_dh_off;
 	struct net_device *netdev = (struct net_device *)arg;
 	struct octeon_droq *droq = container_of(param, struct octeon_droq,
 						napi);

@@ -2308,6 +2309,8 @@ liquidio_push_packet(u32 octeon_id __attribute__((unused)),
 			put_page(pg_info->page);
 		}
 
+		r_dh_off = (rh->r_dh.len - 1) * BYTES_PER_DHLEN_UNIT;
+
 		if (((oct->chip_id == OCTEON_CN66XX) ||
 		     (oct->chip_id == OCTEON_CN68XX)) &&
 		    ptp_enable) {

@@ -2320,16 +2323,26 @@ liquidio_push_packet(u32 octeon_id __attribute__((unused)),
 					/* Nanoseconds are in the first 64-bits
 					 * of the packet.
 					 */
-					memcpy(&ns, (skb->data), sizeof(ns));
+					memcpy(&ns, (skb->data + r_dh_off),
+					       sizeof(ns));
+					r_dh_off -= BYTES_PER_DHLEN_UNIT;
 					shhwtstamps = skb_hwtstamps(skb);
 					shhwtstamps->hwtstamp =
 						ns_to_ktime(ns +
 							    lio->ptp_adjust);
 				}
-				skb_pull(skb, sizeof(ns));
 			}
 		}
 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));
+
+			skb_set_hash(skb, hash, PKT_HASH_TYPE_L4);
+			r_dh_off -= BYTES_PER_DHLEN_UNIT;
+		}
+
+		skb_pull(skb, rh->r_dh.len * BYTES_PER_DHLEN_UNIT);
+
 		skb->protocol = eth_type_trans(skb, skb->dev);
 		if ((netdev->features & NETIF_F_RXCSUM) &&
 		    (((rh->r_dh.encap_on) &&

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
index 70d96c1..c0ee746 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_vf_main.c

@@ -1497,6 +1497,7 @@ liquidio_push_packet(u32 octeon_id __attribute__((unused)),
 	struct net_device *netdev = (struct net_device *)arg;
 	struct sk_buff *skb = (struct sk_buff *)skbuff;
 	u16 vtag = 0;
+	u32 r_dh_off;
 
 	if (netdev) {
 		struct lio *lio = GET_LIO(netdev);

@@ -1540,7 +1541,19 @@ liquidio_push_packet(u32 octeon_id __attribute__((unused)),
 			put_page(pg_info->page);
 		}
 
-		skb_pull(skb, rh->r_dh.len * 8);
+		r_dh_off = (rh->r_dh.len - 1) * BYTES_PER_DHLEN_UNIT;
+
+		if (rh->r_dh.has_hwtstamp)
+			r_dh_off -= BYTES_PER_DHLEN_UNIT;
+
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));
+
+			skb_set_hash(skb, hash, PKT_HASH_TYPE_L4);
+			r_dh_off -= BYTES_PER_DHLEN_UNIT;
+		}
+
+		skb_pull(skb, rh->r_dh.len * BYTES_PER_DHLEN_UNIT);
 		skb->protocol = eth_type_trans(skb, skb->dev);
 
 		if ((netdev->features & NETIF_F_RXCSUM) &&

diff --git a/drivers/net/ethernet/cavium/liquidio/liquidio_common.h b/drivers/net/ethernet/cavium/liquidio/liquidio_common.h
index ba329f6..bc0af8a 100644
--- a/drivers/net/ethernet/cavium/liquidio/liquidio_common.h
+++ b/drivers/net/ethernet/cavium/liquidio/liquidio_common.h

@@ -98,6 +98,8 @@ enum octeon_tag_type {
 #define CVM_DRV_INVALID_APP         (CVM_DRV_APP_START + 0x2)
 #define CVM_DRV_APP_END             (CVM_DRV_INVALID_APP - 1)
 
+#define BYTES_PER_DHLEN_UNIT        8
+
 static inline u32 incr_index(u32 index, u32 count, u32 max)
 {
 	if ((index + count) >= max)

From: Felix Manlunas <redacted>
Date: Fri, 6 Jan 2017 16:55:42 -0800

 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));

Is the checksum defined to be in the first 4-bytes of the 8-byte DHLEN unit,
or the second 4-bytes?  Is the answer to this question endian-dependent?

David Miller [off-list ref] wrote on Sun [2017-Jan-08 17:09:41 -0500]:

From: Felix Manlunas <redacted>
Date: Fri, 6 Jan 2017 16:55:42 -0800

quoted

 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));

Is the checksum defined to be in the first 4-bytes of the 8-byte DHLEN unit,
or the second 4-bytes?  Is the answer to this question endian-dependent?

The hash is always in the first 4-bytes.  The location of the hash is endian
independent.  The hash itself (in its original form) is big endian.

On Fri, 2017-01-06 at 16:55 -0800, Felix Manlunas wrote:

From: Prasad Kanneganti <redacted>

Store the L4 hash of received packets in the skb; the hash is computed in
the NIC firmware.

...

 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));

sparse should complain on this line, right ?

make C=2 CF=-D__CHECK_ENDIAN__ M=drivers/net/ethernet/cavium

From: Felix Manlunas <redacted>
Date: Mon, 9 Jan 2017 10:45:05 -0800

David Miller [off-list ref] wrote on Sun [2017-Jan-08 17:09:41 -0500]:

quoted

From: Felix Manlunas <redacted>
Date: Fri, 6 Jan 2017 16:55:42 -0800

quoted

 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));

Is the checksum defined to be in the first 4-bytes of the 8-byte DHLEN unit,
or the second 4-bytes?  Is the answer to this question endian-dependent?

The hash is always in the first 4-bytes.  The location of the hash is endian
independent.  The hash itself (in its original form) is big endian.

Thanks for explaining.

Please fix the SPARSE issue Eric Dumazet mentioned.

David Miller [off-list ref] wrote on Mon [2017-Jan-09 13:56:21 -0500]:

From: Felix Manlunas <redacted>
Date: Mon, 9 Jan 2017 10:45:05 -0800

quoted

David Miller [off-list ref] wrote on Sun [2017-Jan-08 17:09:41 -0500]:

quoted

From: Felix Manlunas <redacted>
Date: Fri, 6 Jan 2017 16:55:42 -0800

quoted

 
+		if (rh->r_dh.has_hash) {
+			u32 hash = be32_to_cpu(*(u32 *)(skb->data + r_dh_off));

Is the checksum defined to be in the first 4-bytes of the 8-byte DHLEN unit,
or the second 4-bytes?  Is the answer to this question endian-dependent?

The hash is always in the first 4-bytes.  The location of the hash is endian
independent.  The hash itself (in its original form) is big endian.

Thanks for explaining.

Please fix the SPARSE issue Eric Dumazet mentioned.

Will do.  Thanks.