Merge branch 'support-symmetric-xor-rss-hash'

Ahmed Zaki says:

====================
Support symmetric-xor RSS hash

Patches 1 and 2 modify the get/set_rxh ethtool API to take a pointer to
struct of parameters instead of individual params. This will allow future
changes to the uAPI-shared struct ethtool_rxfh without changing the
drivers' API.

Patch 3 adds the support at the Kernel level, allowing the user to set a
symmetric-xor RSS hash for a netdevice via:

    # ethtool -X eth0 hfunc toeplitz symmetric-xor

and clears the flag via:

    # ethtool -X eth0 hfunc toeplitz

The "symmetric-xor" is set in a new "input_xfrm" field in struct
ethtool_rxfh. Support for the new "symmetric-xor" flag will be later sent
to the "ethtool" user-space tool.

Patch 4 fixes a long standing bug with the ice hash function register
values. The bug has been benign for now since only (asymmetric) Toeplitz
hash (Zero) has been used.

Patches 5 and 6 lay some groundwork refactoring. While the first is
mainly cosmetic, the second is needed since there is no more room in the
previous 64-bit RSS profile ID for the symmetric attribute introduced in
the next patch.

Finally, patches 7 and 8 add the symmetric-xor support for the ice
(E800 PFs) and the iAVF drivers.
====================

Link: https://lore.kernel.org/r/20231213003321.605376-1-ahmed.zaki@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 69 insertions, 26 deletions

diff --git a/include/linux/avf/virtchnl.h b/include/linux/avf/virtchnl.h
index 6b3acf15be5c..a44d9dc7e3eb 100644
--- a/include/linux/avf/virtchnl.h
+++ b/include/linux/avf/virtchnl.h
@@ -118,6 +118,7 @@ enum virtchnl_ops {
 	VIRTCHNL_OP_GET_STATS = 15,
 	VIRTCHNL_OP_RSVD = 16,
 	VIRTCHNL_OP_EVENT = 17, /* must ALWAYS be 17 */
+	VIRTCHNL_OP_CONFIG_RSS_HFUNC = 18,
 	/* opcode 19 is reserved */
 	VIRTCHNL_OP_IWARP = 20, /* advanced opcode */
 	VIRTCHNL_OP_RDMA = VIRTCHNL_OP_IWARP,
@@ -911,6 +912,29 @@ struct virtchnl_rss_hena {
 
 VIRTCHNL_CHECK_STRUCT_LEN(8, virtchnl_rss_hena);
 
+/* Type of RSS algorithm */
+enum virtchnl_rss_algorithm {
+	VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC	= 0,
+	VIRTCHNL_RSS_ALG_R_ASYMMETRIC		= 1,
+	VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC	= 2,
+	VIRTCHNL_RSS_ALG_XOR_SYMMETRIC		= 3,
+};
+
+/* VIRTCHNL_OP_CONFIG_RSS_HFUNC
+ * VF sends this message to configure the RSS hash function. Only supported
+ * if both PF and VF drivers set the VIRTCHNL_VF_OFFLOAD_RSS_PF bit during
+ * configuration negotiation.
+ * The hash function is initialized to VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC
+ * by the PF.
+ */
+struct virtchnl_rss_hfunc {
+	u16 vsi_id;
+	u16 rss_algorithm; /* enum virtchnl_rss_algorithm */
+	u32 reserved;
+};
+
+VIRTCHNL_CHECK_STRUCT_LEN(8, virtchnl_rss_hfunc);
+
 /* VIRTCHNL_OP_ENABLE_CHANNELS
  * VIRTCHNL_OP_DISABLE_CHANNELS
  * VF sends these messages to enable or disable channels based on
@@ -1095,14 +1119,6 @@ enum virtchnl_vfr_states {
 	VIRTCHNL_VFR_VFACTIVE,
 };
 
-/* Type of RSS algorithm */
-enum virtchnl_rss_algorithm {
-	VIRTCHNL_RSS_ALG_TOEPLITZ_ASYMMETRIC	= 0,
-	VIRTCHNL_RSS_ALG_R_ASYMMETRIC		= 1,
-	VIRTCHNL_RSS_ALG_TOEPLITZ_SYMMETRIC	= 2,
-	VIRTCHNL_RSS_ALG_XOR_SYMMETRIC		= 3,
-};
-
 #define VIRTCHNL_MAX_NUM_PROTO_HDRS	32
 #define PROTO_HDR_SHIFT			5
 #define PROTO_HDR_FIELD_START(proto_hdr_type) ((proto_hdr_type) << PROTO_HDR_SHIFT)
@@ -1542,6 +1558,9 @@ virtchnl_vc_validate_vf_msg(struct virtchnl_version_info *ver, u32 v_opcode,
 							 vrl->lut_entries);
 		}
 		break;
+	case VIRTCHNL_OP_CONFIG_RSS_HFUNC:
+		valid_len = sizeof(struct virtchnl_rss_hfunc);
+		break;
 	case VIRTCHNL_OP_GET_RSS_HENA_CAPS:
 		break;
 	case VIRTCHNL_OP_SET_RSS_HENA:
diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index 67b30940234b..cfcd952a1d4f 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -597,9 +597,46 @@ struct ethtool_mm_stats {
 };
 
 /**
+ * struct ethtool_rxfh_param - RXFH (RSS) parameters
+ * @hfunc: Defines the current RSS hash function used by HW (or to be set to).
+ *	Valid values are one of the %ETH_RSS_HASH_*.
+ * @indir_size: On SET, the array size of the user buffer for the
+ *	indirection table, which may be zero, or
+ *	%ETH_RXFH_INDIR_NO_CHANGE.  On GET (read from the driver),
+ *	the array size of the hardware indirection table.
+ * @indir: The indirection table of size @indir_size entries.
+ * @key_size: On SET, the array size of the user buffer for the hash key,
+ *	which may be zero.  On GET (read from the driver), the size of the
+ *	hardware hash key.
+ * @key: The hash key of size @key_size bytes.
+ * @rss_context: RSS context identifier.  Context 0 is the default for normal
+ *	traffic; other contexts can be referenced as the destination for RX flow
+ *	classification rules.  On SET, %ETH_RXFH_CONTEXT_ALLOC is used
+ *	to allocate a new RSS context; on return this field will
+ *	contain the ID of the newly allocated context.
+ * @rss_delete: Set to non-ZERO to remove the @rss_context context.
+ * @input_xfrm: Defines how the input data is transformed. Valid values are one
+ *	of %RXH_XFRM_*.
+ */
+struct ethtool_rxfh_param {
+	u8	hfunc;
+	u32	indir_size;
+	u32	*indir;
+	u32	key_size;
+	u8	*key;
+	u32	rss_context;
+	u8	rss_delete;
+	u8	input_xfrm;
+};
+
+/**
  * struct ethtool_ops - optional netdev operations
  * @cap_link_lanes_supported: indicates if the driver supports lanes
  *	parameter.
+ * @cap_rss_ctx_supported: indicates if the driver supports RSS
+ *	contexts.
+ * @cap_rss_sym_xor_supported: indicates if the driver supports symmetric-xor
+ *	RSS.
  * @supported_coalesce_params: supported types of interrupt coalescing.
  * @supported_ring_params: supported ring params.
  * @get_drvinfo: Report driver/device information. Modern drivers no
@@ -696,15 +733,6 @@ struct ethtool_mm_stats {
  *	will remain unchanged.
  *	Returns a negative error code or zero. An error code must be returned
  *	if at least one unsupported change was requested.
- * @get_rxfh_context: Get the contents of the RX flow hash indirection table,
- *	hash key, and/or hash function assiciated to the given rss context.
- *	Returns a negative error code or zero.
- * @set_rxfh_context: Create, remove and configure RSS contexts. Allows setting
- *	the contents of the RX flow hash indirection table, hash key, and/or
- *	hash function associated to the given context. Arguments which are set
- *	to %NULL or zero will remain unchanged.
- *	Returns a negative error code or zero. An error code must be returned
- *	if at least one unsupported change was requested.
  * @get_channels: Get number of channels.
  * @set_channels: Set number of channels.  Returns a negative error code or
  *	zero.
@@ -787,6 +815,8 @@ struct ethtool_mm_stats {
  */
 struct ethtool_ops {
 	u32     cap_link_lanes_supported:1;
+	u32     cap_rss_ctx_supported:1;
+	u32	cap_rss_sym_xor_supported:1;
 	u32	supported_coalesce_params;
 	u32	supported_ring_params;
 	void	(*get_drvinfo)(struct net_device *, struct ethtool_drvinfo *);
@@ -846,15 +876,9 @@ struct ethtool_ops {
 	int	(*reset)(struct net_device *, u32 *);
 	u32	(*get_rxfh_key_size)(struct net_device *);
 	u32	(*get_rxfh_indir_size)(struct net_device *);
-	int	(*get_rxfh)(struct net_device *, u32 *indir, u8 *key,
-			    u8 *hfunc);
-	int	(*set_rxfh)(struct net_device *, const u32 *indir,
-			    const u8 *key, const u8 hfunc);
-	int	(*get_rxfh_context)(struct net_device *, u32 *indir, u8 *key,
-				    u8 *hfunc, u32 rss_context);
-	int	(*set_rxfh_context)(struct net_device *, const u32 *indir,
-				    const u8 *key, const u8 hfunc,
-				    u32 *rss_context, bool delete);
+	int	(*get_rxfh)(struct net_device *, struct ethtool_rxfh_param *);
+	int	(*set_rxfh)(struct net_device *, struct ethtool_rxfh_param *,
+			    struct netlink_ext_ack *extack);
 	void	(*get_channels)(struct net_device *, struct ethtool_channels *);
 	int	(*set_channels)(struct net_device *, struct ethtool_channels *);
 	int	(*get_dump_flag)(struct net_device *, struct ethtool_dump *);