Merge branch 'eth-bnxt-use-the-new-rss-api'

Jakub Kicinski says:

====================
eth: bnxt: use the new RSS API

Convert bnxt from using the set_rxfh API to separate create/modify/remove
callbacks.

Two small extensions to the core APIs are necessary:
 - the ability to discard contexts if for some catastrophic reasons
   device can no longer provide them;
 - the ability to reserve space in the context for RSS table growth.

The driver is adjusted to store indirection tables on u32 to make
it easier to use core structs directly.

With that out of the way the conversion is fairly straightforward.

Since the opposition to discarding contexts was relatively mild
and its what bnxt does already, I'm sticking to that. We may very
well need to revisit that at a later time.

v1: https://lore.kernel.org/all/20240702234757.4188344-1-kuba@kernel.org/
====================

Link: https://patch.msgid.link/20240711220713.283778-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 9 insertions, 11 deletions

diff --git a/include/linux/ethtool.h b/include/linux/ethtool.h
index e213b5508da6..a1ee76936f53 100644
--- a/include/linux/ethtool.h
+++ b/include/linux/ethtool.h
@@ -181,6 +181,7 @@ struct ethtool_rxfh_context {
 	/* private: driver private data, indirection table, and hash key are
 	 * stored sequentially in @data area.  Use below helpers to access.
 	 */
+	u32 key_off;
 	u8 data[] __aligned(sizeof(void *));
 };
 
@@ -196,19 +197,10 @@ static inline u32 *ethtool_rxfh_context_indir(struct ethtool_rxfh_context *ctx)
 
 static inline u8 *ethtool_rxfh_context_key(struct ethtool_rxfh_context *ctx)
 {
-	return (u8 *)(ethtool_rxfh_context_indir(ctx) + ctx->indir_size);
+	return &ctx->data[ctx->key_off];
 }
 
-static inline size_t ethtool_rxfh_context_size(u32 indir_size, u32 key_size,
-					       u16 priv_size)
-{
-	size_t indir_bytes = array_size(indir_size, sizeof(u32));
-	size_t flex_len;
-
-	flex_len = size_add(size_add(indir_bytes, key_size),
-			    ALIGN(priv_size, sizeof(u32)));
-	return struct_size_t(struct ethtool_rxfh_context, data, flex_len);
-}
+void ethtool_rxfh_context_lost(struct net_device *dev, u32 context_id);
 
 /* declare a link mode bitmap */
 #define __ETHTOOL_DECLARE_LINK_MODE_MASK(name)		\
@@ -721,6 +713,10 @@ struct ethtool_rxfh_param {
  *	contexts.
  * @cap_rss_sym_xor_supported: indicates if the driver supports symmetric-xor
  *	RSS.
+ * @rxfh_indir_space: max size of RSS indirection tables, if indirection table
+ *	size as returned by @get_rxfh_indir_size may change during lifetime
+ *	of the device. Leave as 0 if the table size is constant.
+ * @rxfh_key_space: same as @rxfh_indir_space, but for the key.
  * @rxfh_priv_size: size of the driver private data area the core should
  *	allocate for an RSS context (in &struct ethtool_rxfh_context).
  * @rxfh_max_context_id: maximum (exclusive) supported RSS context ID.  If this
@@ -938,6 +934,8 @@ struct ethtool_ops {
 	u32     cap_link_lanes_supported:1;
 	u32     cap_rss_ctx_supported:1;
 	u32	cap_rss_sym_xor_supported:1;
+	u32	rxfh_indir_space;
+	u16	rxfh_key_space;
 	u16	rxfh_priv_size;
 	u32	rxfh_max_context_id;
 	u32	supported_coalesce_params;