[xdp-hints] [PATCH bpf V6 2/5] mlx5: bpf_xdp_metadata_rx_hash add xdp rss hash type

[Jesper Dangaard Brouer <brouer@redhat.com>]

Update API for bpf_xdp_metadata_rx_hash() with arg for xdp rss hash type
via mapping table.

The mlx5 hardware can also identify and RSS hash IPSEC.  This indicate
hash includes SPI (Security Parameters Index) as part of IPSEC hash.

Extend xdp core enum xdp_rss_hash_type with IPSEC hash type.

Fixes: bc8d405b1ba9 ("net/mlx5e: Support RX XDP metadata")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c |   60 ++++++++++++++++++++++
 include/linux/mlx5/device.h                      |   14 ++++-
 include/net/xdp.h                                |    2 +
 3 files changed, 73 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
index efe609f8e3aa..97ef1df94d50 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/xdp.c
@@ -34,6 +34,7 @@
 #include <net/xdp_sock_drv.h>
 #include "en/xdp.h"
 #include "en/params.h"
+#include <linux/bitfield.h>
 
 int mlx5e_xdp_max_mtu(struct mlx5e_params *params, struct mlx5e_xsk_param *xsk)
 {
@@ -169,15 +170,72 @@ static int mlx5e_xdp_rx_timestamp(const struct xdp_md *ctx, u64 *timestamp)
 	return 0;
 }
 
+/* Mapping HW RSS Type bits CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 into 4-bits*/
+#define RSS_TYPE_MAX_TABLE	16 /* 4-bits max 16 entries */
+#define RSS_L4		GENMASK(1, 0)
+#define RSS_L3		GENMASK(3, 2) /* Same as CQE_RSS_HTYPE_IP */
+
+/* Valid combinations of CQE_RSS_HTYPE_IP + CQE_RSS_HTYPE_L4 sorted numerical */
+enum mlx5_rss_hash_type {
+	RSS_TYPE_NO_HASH	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IP_NONE) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+	RSS_TYPE_L3_IPV4	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+	RSS_TYPE_L4_IPV4_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
+	RSS_TYPE_L4_IPV4_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
+	RSS_TYPE_L4_IPV4_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV4) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
+	RSS_TYPE_L3_IPV6	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_NONE)),
+	RSS_TYPE_L4_IPV6_TCP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_TCP)),
+	RSS_TYPE_L4_IPV6_UDP	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_UDP)),
+	RSS_TYPE_L4_IPV6_IPSEC	= (FIELD_PREP_CONST(RSS_L3, CQE_RSS_IPV6) |
+				   FIELD_PREP_CONST(RSS_L4, CQE_RSS_L4_IPSEC)),
+} mlx5_rss_hash_type;
+
+/* Invalid combinations will simply return zero, allows no boundary checks */
+static const enum xdp_rss_hash_type mlx5_xdp_rss_type[RSS_TYPE_MAX_TABLE] = {
+	[RSS_TYPE_NO_HASH]	 = XDP_RSS_TYPE_NONE,
+	[1]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[2]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[3]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[RSS_TYPE_L3_IPV4]	 = XDP_RSS_TYPE_L3_IPV4,
+	[RSS_TYPE_L4_IPV4_TCP]	 = XDP_RSS_TYPE_L4_IPV4_TCP,
+	[RSS_TYPE_L4_IPV4_UDP]	 = XDP_RSS_TYPE_L4_IPV4_UDP,
+	[RSS_TYPE_L4_IPV4_IPSEC] = XDP_RSS_TYPE_L4_IPV4_IPSEC,
+	[RSS_TYPE_L3_IPV6]	 = XDP_RSS_TYPE_L3_IPV6,
+	[RSS_TYPE_L4_IPV6_TCP]	 = XDP_RSS_TYPE_L4_IPV6_TCP,
+	[RSS_TYPE_L4_IPV6_UDP]   = XDP_RSS_TYPE_L4_IPV6_UDP,
+	[RSS_TYPE_L4_IPV6_IPSEC] = XDP_RSS_TYPE_L4_IPV6_IPSEC,
+	[12]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[13]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[14]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+	[15]			 = XDP_RSS_TYPE_NONE, /* Implicit zero */
+};
+
 static int mlx5e_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
 			     enum xdp_rss_hash_type *rss_type)
 {
 	const struct mlx5e_xdp_buff *_ctx = (void *)ctx;
+	const struct mlx5_cqe64 *cqe = _ctx->cqe;
+	u32 hash_type, l4_type, ip_type, lookup;
 
 	if (unlikely(!(_ctx->xdp.rxq->dev->features & NETIF_F_RXHASH)))
 		return -ENODATA;
 
-	*hash = be32_to_cpu(_ctx->cqe->rss_hash_result);
+	*hash = be32_to_cpu(cqe->rss_hash_result);
+
+	hash_type = cqe->rss_hash_type;
+	BUILD_BUG_ON(CQE_RSS_HTYPE_IP != RSS_L3); /* same mask */
+	ip_type = hash_type & CQE_RSS_HTYPE_IP;
+	l4_type = FIELD_GET(CQE_RSS_HTYPE_L4, hash_type);
+	lookup = ip_type | l4_type;
+	*rss_type = mlx5_xdp_rss_type[lookup];
+
 	return 0;
 }
 
diff --git a/include/linux/mlx5/device.h b/include/linux/mlx5/device.h
index 71b06ebad402..1db19a9d26e3 100644
--- a/include/linux/mlx5/device.h
+++ b/include/linux/mlx5/device.h
@@ -36,6 +36,7 @@
 #include <linux/types.h>
 #include <rdma/ib_verbs.h>
 #include <linux/mlx5/mlx5_ifc.h>
+#include <linux/bitfield.h>
 
 #if defined(__LITTLE_ENDIAN)
 #define MLX5_SET_HOST_ENDIANNESS	0
@@ -980,14 +981,23 @@ enum {
 };
 
 enum {
-	CQE_RSS_HTYPE_IP	= 0x3 << 2,
+	CQE_RSS_HTYPE_IP	= GENMASK(3, 2),
 	/* cqe->rss_hash_type[3:2] - IP destination selected for hash
 	 * (00 = none,  01 = IPv4, 10 = IPv6, 11 = Reserved)
 	 */
-	CQE_RSS_HTYPE_L4	= 0x3 << 6,
+	CQE_RSS_IP_NONE		= 0x0,
+	CQE_RSS_IPV4		= 0x1,
+	CQE_RSS_IPV6		= 0x2,
+	CQE_RSS_RESERVED	= 0x3,
+
+	CQE_RSS_HTYPE_L4	= GENMASK(7, 6),
 	/* cqe->rss_hash_type[7:6] - L4 destination selected for hash
 	 * (00 = none, 01 = TCP. 10 = UDP, 11 = IPSEC.SPI
 	 */
+	CQE_RSS_L4_NONE		= 0x0,
+	CQE_RSS_L4_TCP		= 0x1,
+	CQE_RSS_L4_UDP		= 0x2,
+	CQE_RSS_L4_IPSEC	= 0x3,
 };
 
 enum {
diff --git a/include/net/xdp.h b/include/net/xdp.h
index a76c4ea203ea..76aa748e7923 100644
--- a/include/net/xdp.h
+++ b/include/net/xdp.h
@@ -460,10 +460,12 @@ enum xdp_rss_hash_type {
 	XDP_RSS_TYPE_L4_IPV4_TCP     = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
 	XDP_RSS_TYPE_L4_IPV4_UDP     = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
 	XDP_RSS_TYPE_L4_IPV4_SCTP    = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+	XDP_RSS_TYPE_L4_IPV4_IPSEC   = XDP_RSS_L3_IPV4 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,
 
 	XDP_RSS_TYPE_L4_IPV6_TCP     = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_TCP,
 	XDP_RSS_TYPE_L4_IPV6_UDP     = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_UDP,
 	XDP_RSS_TYPE_L4_IPV6_SCTP    = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_SCTP,
+	XDP_RSS_TYPE_L4_IPV6_IPSEC   = XDP_RSS_L3_IPV6 | XDP_RSS_L4 | XDP_RSS_L4_IPSEC,
 
 	XDP_RSS_TYPE_L4_IPV6_TCP_EX  = XDP_RSS_TYPE_L4_IPV6_TCP  | XDP_RSS_L3_DYNHDR,
 	XDP_RSS_TYPE_L4_IPV6_UDP_EX  = XDP_RSS_TYPE_L4_IPV6_UDP  | XDP_RSS_L3_DYNHDR,