diff mbox series

[v3,net-next,14/14] mlx5: support BIG TCP packets

Message ID 20220310002846.460907-15-eric.dumazet@gmail.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series tcp: BIG TCP implementation | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit fail Errors and warnings before: 0 this patch: 8
netdev/cc_maintainers warning 1 maintainers not CCed: linux-rdma@vger.kernel.org
netdev/build_clang fail Errors and warnings before: 0 this patch: 13
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn fail Errors and warnings before: 0 this patch: 8
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 82 exceeds 80 columns WARNING: line length of 86 exceeds 80 columns WARNING: line length of 87 exceeds 80 columns WARNING: line length of 88 exceeds 80 columns WARNING: line length of 90 exceeds 80 columns WARNING: line length of 91 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Eric Dumazet March 10, 2022, 12:28 a.m. UTC
From: Coco Li <lixiaoyan@google.com>

mlx5 supports LSOv2.

IPv6 gro/tcp stacks insert a temporary Hop-by-Hop header
with JUMBO TLV for big packets.

We need to ignore/skip this HBH header when populating TX descriptor.

Note that ipv6_has_hopopt_jumbo() only recognizes very specific packet
layout, thus mlx5e_sq_xmit_wqe() is taking care of this layout only.

v2: clear hopbyhop in mlx5e_tx_get_gso_ihs()

Signed-off-by: Coco Li <lixiaoyan@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Tariq Toukan <tariqt@nvidia.com>
Cc: Saeed Mahameed <saeedm@nvidia.com>
Cc: Leon Romanovsky <leon@kernel.org>
---
 .../net/ethernet/mellanox/mlx5/core/en_main.c |  1 +
 .../net/ethernet/mellanox/mlx5/core/en_tx.c   | 82 +++++++++++++++----
 2 files changed, 67 insertions(+), 16 deletions(-)

Comments

Jakub Kicinski March 10, 2022, 4:44 a.m. UTC | #1
On Wed,  9 Mar 2022 16:28:46 -0800 Eric Dumazet wrote:
> @@ -918,12 +953,27 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
>  	eseg->mss = attr.mss;
>  
>  	if (attr.ihs) {
> -		memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> +		if (unlikely(attr.hopbyhop)) {
> +			/* remove the HBH header.
> +			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
> +			 */
> +			memcpy(eseg->inline_hdr.start, skb->data, ETH_HLEN + sizeof(*h6));
> +			h6 = (struct ipv6hdr *)((char *)eseg->inline_hdr.start + ETH_HLEN);
> +			h6->nexthdr = IPPROTO_TCP;
> +			/* Copy the TCP header after the IPv6 one */
> +			memcpy(h6 + 1,
> +			       skb->data + ETH_HLEN + sizeof(*h6) +
> +					sizeof(struct hop_jumbo_hdr),
> +			       tcp_hdrlen(skb));
> +			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
> +		} else {
> +			memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> +		}

Compiler says there's no h6 in mlx5i_sq_xmit().
Eric Dumazet March 10, 2022, 5:40 a.m. UTC | #2
On Wed, Mar 9, 2022 at 8:44 PM Jakub Kicinski <kuba@kernel.org> wrote:
>
> On Wed,  9 Mar 2022 16:28:46 -0800 Eric Dumazet wrote:
> > @@ -918,12 +953,27 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
> >       eseg->mss = attr.mss;
> >
> >       if (attr.ihs) {
> > -             memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> > +             if (unlikely(attr.hopbyhop)) {
> > +                     /* remove the HBH header.
> > +                      * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
> > +                      */
> > +                     memcpy(eseg->inline_hdr.start, skb->data, ETH_HLEN + sizeof(*h6));
> > +                     h6 = (struct ipv6hdr *)((char *)eseg->inline_hdr.start + ETH_HLEN);
> > +                     h6->nexthdr = IPPROTO_TCP;
> > +                     /* Copy the TCP header after the IPv6 one */
> > +                     memcpy(h6 + 1,
> > +                            skb->data + ETH_HLEN + sizeof(*h6) +
> > +                                     sizeof(struct hop_jumbo_hdr),
> > +                            tcp_hdrlen(skb));
> > +                     /* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
> > +             } else {
> > +                     memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> > +             }
>
> Compiler says there's no h6 in mlx5i_sq_xmit().

Ah, we missed CONFIG_MLX5_CORE_IPOIB=y it seems.

Let me take a look before sending the fix.
Eric Dumazet March 10, 2022, 5:43 a.m. UTC | #3
On Wed, Mar 9, 2022 at 9:40 PM Eric Dumazet <edumazet@google.com> wrote:
>
> On Wed, Mar 9, 2022 at 8:44 PM Jakub Kicinski <kuba@kernel.org> wrote:
> >
> > On Wed,  9 Mar 2022 16:28:46 -0800 Eric Dumazet wrote:
> > > @@ -918,12 +953,27 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
> > >       eseg->mss = attr.mss;
> > >
> > >       if (attr.ihs) {
> > > -             memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> > > +             if (unlikely(attr.hopbyhop)) {
> > > +                     /* remove the HBH header.
> > > +                      * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
> > > +                      */
> > > +                     memcpy(eseg->inline_hdr.start, skb->data, ETH_HLEN + sizeof(*h6));
> > > +                     h6 = (struct ipv6hdr *)((char *)eseg->inline_hdr.start + ETH_HLEN);
> > > +                     h6->nexthdr = IPPROTO_TCP;
> > > +                     /* Copy the TCP header after the IPv6 one */
> > > +                     memcpy(h6 + 1,
> > > +                            skb->data + ETH_HLEN + sizeof(*h6) +
> > > +                                     sizeof(struct hop_jumbo_hdr),
> > > +                            tcp_hdrlen(skb));
> > > +                     /* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
> > > +             } else {
> > > +                     memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
> > > +             }
> >
> > Compiler says there's no h6 in mlx5i_sq_xmit().
>
> Ah, we missed CONFIG_MLX5_CORE_IPOIB=y it seems.
>
> Let me take a look before sending the fix.

I will squash this:

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index c6f6ca2d216692e1d3fd99e540198b11145788cd..b4fc45ba1b347fb9ad0f46b9c091cc45e4d3d84f
100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -954,6 +954,8 @@ void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct
sk_buff *skb,

        if (attr.ihs) {
                if (unlikely(attr.hopbyhop)) {
+                       struct ipv6hdr *h6;
+
                        /* remove the HBH header.
                         * Layout: [Ethernet header][IPv6
header][HBH][TCP header]
                         */
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
index b2ed2f6d4a9208aebfd17fd0c503cd1e37c39ee1..1e51ce1d74486392a26568852c5068fe9047296d 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_main.c
@@ -4910,6 +4910,7 @@  static void mlx5e_build_nic_netdev(struct net_device *netdev)
 
 	netdev->priv_flags       |= IFF_UNICAST_FLT;
 
+	netif_set_tso_ipv6_max_size(netdev, 512 * 1024);
 	mlx5e_set_netdev_dev_addr(netdev);
 	mlx5e_ipsec_build_netdev(priv);
 	mlx5e_tls_build_netdev(priv);
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
index 2dc48406cd08d21ff94f665cd61ab9227f351215..c6f6ca2d216692e1d3fd99e540198b11145788cd 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tx.c
@@ -40,6 +40,7 @@ 
 #include "en_accel/en_accel.h"
 #include "en_accel/ipsec_rxtx.h"
 #include "en/ptp.h"
+#include <net/ipv6.h>
 
 static void mlx5e_dma_unmap_wqe_err(struct mlx5e_txqsq *sq, u8 num_dma)
 {
@@ -130,23 +131,32 @@  mlx5e_txwqe_build_eseg_csum(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 		sq->stats->csum_none++;
 }
 
+/* Returns the number of header bytes that we plan
+ * to inline later in the transmit descriptor
+ */
 static inline u16
-mlx5e_tx_get_gso_ihs(struct mlx5e_txqsq *sq, struct sk_buff *skb)
+mlx5e_tx_get_gso_ihs(struct mlx5e_txqsq *sq, struct sk_buff *skb, int *hopbyhop)
 {
 	struct mlx5e_sq_stats *stats = sq->stats;
 	u16 ihs;
 
+	*hopbyhop = 0;
 	if (skb->encapsulation) {
 		ihs = skb_inner_transport_offset(skb) + inner_tcp_hdrlen(skb);
 		stats->tso_inner_packets++;
 		stats->tso_inner_bytes += skb->len - ihs;
 	} else {
-		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4)
+		if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
 			ihs = skb_transport_offset(skb) + sizeof(struct udphdr);
-		else
+		} else {
 			ihs = skb_transport_offset(skb) + tcp_hdrlen(skb);
+			if (ipv6_has_hopopt_jumbo(skb)) {
+				*hopbyhop = sizeof(struct hop_jumbo_hdr);
+				ihs -= sizeof(struct hop_jumbo_hdr);
+			}
+		}
 		stats->tso_packets++;
-		stats->tso_bytes += skb->len - ihs;
+		stats->tso_bytes += skb->len - ihs - *hopbyhop;
 	}
 
 	return ihs;
@@ -208,6 +218,7 @@  struct mlx5e_tx_attr {
 	__be16 mss;
 	u16 insz;
 	u8 opcode;
+	u8 hopbyhop;
 };
 
 struct mlx5e_tx_wqe_attr {
@@ -244,14 +255,16 @@  static void mlx5e_sq_xmit_prepare(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	struct mlx5e_sq_stats *stats = sq->stats;
 
 	if (skb_is_gso(skb)) {
-		u16 ihs = mlx5e_tx_get_gso_ihs(sq, skb);
+		int hopbyhop;
+		u16 ihs = mlx5e_tx_get_gso_ihs(sq, skb, &hopbyhop);
 
 		*attr = (struct mlx5e_tx_attr) {
 			.opcode    = MLX5_OPCODE_LSO,
 			.mss       = cpu_to_be16(skb_shinfo(skb)->gso_size),
 			.ihs       = ihs,
 			.num_bytes = skb->len + (skb_shinfo(skb)->gso_segs - 1) * ihs,
-			.headlen   = skb_headlen(skb) - ihs,
+			.headlen   = skb_headlen(skb) - ihs - hopbyhop,
+			.hopbyhop  = hopbyhop,
 		};
 
 		stats->packets += skb_shinfo(skb)->gso_segs;
@@ -365,7 +378,8 @@  mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	struct mlx5_wqe_eth_seg  *eseg;
 	struct mlx5_wqe_data_seg *dseg;
 	struct mlx5e_tx_wqe_info *wi;
-
+	u16 ihs = attr->ihs;
+	struct ipv6hdr *h6;
 	struct mlx5e_sq_stats *stats = sq->stats;
 	int num_dma;
 
@@ -379,15 +393,36 @@  mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 
 	eseg->mss = attr->mss;
 
-	if (attr->ihs) {
-		if (skb_vlan_tag_present(skb)) {
-			eseg->inline_hdr.sz |= cpu_to_be16(attr->ihs + VLAN_HLEN);
-			mlx5e_insert_vlan(eseg->inline_hdr.start, skb, attr->ihs);
+	if (ihs) {
+		u8 *start = eseg->inline_hdr.start;
+
+		if (unlikely(attr->hopbyhop)) {
+			/* remove the HBH header.
+			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
+			 */
+			if (skb_vlan_tag_present(skb)) {
+				mlx5e_insert_vlan(start, skb, ETH_HLEN + sizeof(*h6));
+				ihs += VLAN_HLEN;
+				h6 = (struct ipv6hdr *)(start + sizeof(struct vlan_ethhdr));
+			} else {
+				memcpy(start, skb->data, ETH_HLEN + sizeof(*h6));
+				h6 = (struct ipv6hdr *)(start + ETH_HLEN);
+			}
+			h6->nexthdr = IPPROTO_TCP;
+			/* Copy the TCP header after the IPv6 one */
+			memcpy(h6 + 1,
+			       skb->data + ETH_HLEN + sizeof(*h6) +
+					sizeof(struct hop_jumbo_hdr),
+			       tcp_hdrlen(skb));
+			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
+		} else if (skb_vlan_tag_present(skb)) {
+			mlx5e_insert_vlan(start, skb, ihs);
+			ihs += VLAN_HLEN;
 			stats->added_vlan_packets++;
 		} else {
-			eseg->inline_hdr.sz |= cpu_to_be16(attr->ihs);
-			memcpy(eseg->inline_hdr.start, skb->data, attr->ihs);
+			memcpy(start, skb->data, ihs);
 		}
+		eseg->inline_hdr.sz |= cpu_to_be16(ihs);
 		dseg += wqe_attr->ds_cnt_inl;
 	} else if (skb_vlan_tag_present(skb)) {
 		eseg->insert.type = cpu_to_be16(MLX5_ETH_WQE_INSERT_VLAN);
@@ -398,7 +433,7 @@  mlx5e_sq_xmit_wqe(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	}
 
 	dseg += wqe_attr->ds_cnt_ids;
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr->ihs,
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr->ihs + attr->hopbyhop,
 					  attr->headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;
@@ -918,12 +953,27 @@  void mlx5i_sq_xmit(struct mlx5e_txqsq *sq, struct sk_buff *skb,
 	eseg->mss = attr.mss;
 
 	if (attr.ihs) {
-		memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
+		if (unlikely(attr.hopbyhop)) {
+			/* remove the HBH header.
+			 * Layout: [Ethernet header][IPv6 header][HBH][TCP header]
+			 */
+			memcpy(eseg->inline_hdr.start, skb->data, ETH_HLEN + sizeof(*h6));
+			h6 = (struct ipv6hdr *)((char *)eseg->inline_hdr.start + ETH_HLEN);
+			h6->nexthdr = IPPROTO_TCP;
+			/* Copy the TCP header after the IPv6 one */
+			memcpy(h6 + 1,
+			       skb->data + ETH_HLEN + sizeof(*h6) +
+					sizeof(struct hop_jumbo_hdr),
+			       tcp_hdrlen(skb));
+			/* Leave ipv6 payload_len set to 0, as LSO v2 specs request. */
+		} else {
+			memcpy(eseg->inline_hdr.start, skb->data, attr.ihs);
+		}
 		eseg->inline_hdr.sz = cpu_to_be16(attr.ihs);
 		dseg += wqe_attr.ds_cnt_inl;
 	}
 
-	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr.ihs,
+	num_dma = mlx5e_txwqe_build_dsegs(sq, skb, skb->data + attr.ihs + attr.hopbyhop,
 					  attr.headlen, dseg);
 	if (unlikely(num_dma < 0))
 		goto err_drop;