Merge branch 'ethtool-track-custom-rss-contexts-in-the-core'

Edward Cree says:

====================
ethtool: track custom RSS contexts in the core

Make the core responsible for tracking the set of custom RSS contexts,
 their IDs, indirection tables, hash keys, and hash functions; this
 lets us get rid of duplicative code in drivers, and will allow us to
 support netlink dumps later.

This series only moves the sfc EF10 & EF100 driver over to the new API;
 other drivers (mvpp2, octeontx2, mlx5, sfc/siena, bnxt_en) can be converted
 afterwards and the legacy API removed.
====================

Link: https://patch.msgid.link/cover.1719502239.git.ecree.xilinx@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 128 insertions, 8 deletions

diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c
index 1cca372c0d80..d8795ed07ba3 100644
--- a/net/ethtool/ioctl.c
+++ b/net/ethtool/ioctl.c
@@ -1202,6 +1202,7 @@ static noinline_for_stack int ethtool_get_rxfh(struct net_device *dev,
 	const struct ethtool_ops *ops = dev->ethtool_ops;
 	struct ethtool_rxfh_param rxfh_dev = {};
 	u32 user_indir_size, user_key_size;
+	struct ethtool_rxfh_context *ctx;
 	struct ethtool_rxfh rxfh;
 	u32 indir_bytes;
 	u8 *rss_config;
@@ -1249,11 +1250,26 @@ static noinline_for_stack int ethtool_get_rxfh(struct net_device *dev,
 	if (user_key_size)
 		rxfh_dev.key = rss_config + indir_bytes;
 
-	rxfh_dev.rss_context = rxfh.rss_context;
-
-	ret = dev->ethtool_ops->get_rxfh(dev, &rxfh_dev);
-	if (ret)
-		goto out;
+	if (rxfh.rss_context) {
+		ctx = xa_load(&dev->ethtool->rss_ctx, rxfh.rss_context);
+		if (!ctx) {
+			ret = -ENOENT;
+			goto out;
+		}
+		if (rxfh_dev.indir)
+			memcpy(rxfh_dev.indir, ethtool_rxfh_context_indir(ctx),
+			       indir_bytes);
+		if (rxfh_dev.key)
+			memcpy(rxfh_dev.key, ethtool_rxfh_context_key(ctx),
+			       user_key_size);
+		rxfh_dev.hfunc = ctx->hfunc;
+		rxfh_dev.input_xfrm = ctx->input_xfrm;
+		ret = 0;
+	} else {
+		ret = dev->ethtool_ops->get_rxfh(dev, &rxfh_dev);
+		if (ret)
+			goto out;
+	}
 
 	if (copy_to_user(useraddr + offsetof(struct ethtool_rxfh, hfunc),
 			 &rxfh_dev.hfunc, sizeof(rxfh.hfunc))) {
@@ -1281,10 +1297,13 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 	const struct ethtool_ops *ops = dev->ethtool_ops;
 	u32 dev_indir_size = 0, dev_key_size = 0, i;
 	struct ethtool_rxfh_param rxfh_dev = {};
+	struct ethtool_rxfh_context *ctx = NULL;
 	struct netlink_ext_ack *extack = NULL;
 	struct ethtool_rxnfc rx_rings;
 	struct ethtool_rxfh rxfh;
+	bool locked = false; /* dev->ethtool->rss_lock taken */
 	u32 indir_bytes = 0;
+	bool create = false;
 	u8 *rss_config;
 	int ret;
 
@@ -1312,6 +1331,7 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 	if ((rxfh.input_xfrm & RXH_XFRM_SYM_XOR) &&
 	    !ops->cap_rss_sym_xor_supported)
 		return -EOPNOTSUPP;
+	create = rxfh.rss_context == ETH_RXFH_CONTEXT_ALLOC;
 
 	/* If either indir, hash key or function is valid, proceed further.
 	 * Must request at least one change: indir size, hash key, function
@@ -1377,13 +1397,77 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 		}
 	}
 
+	if (rxfh.rss_context) {
+		mutex_lock(&dev->ethtool->rss_lock);
+		locked = true;
+	}
+	if (create) {
+		if (rxfh_dev.rss_delete) {
+			ret = -EINVAL;
+			goto out;
+		}
+		ctx = kzalloc(ethtool_rxfh_context_size(dev_indir_size,
+							dev_key_size,
+							ops->rxfh_priv_size),
+			      GFP_KERNEL_ACCOUNT);
+		if (!ctx) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		ctx->indir_size = dev_indir_size;
+		ctx->key_size = dev_key_size;
+		ctx->priv_size = ops->rxfh_priv_size;
+		/* Initialise to an empty context */
+		ctx->hfunc = ETH_RSS_HASH_NO_CHANGE;
+		ctx->input_xfrm = RXH_XFRM_NO_CHANGE;
+		if (ops->create_rxfh_context) {
+			u32 limit = ops->rxfh_max_context_id ?: U32_MAX;
+			u32 ctx_id;
+
+			/* driver uses new API, core allocates ID */
+			ret = xa_alloc(&dev->ethtool->rss_ctx, &ctx_id, ctx,
+				       XA_LIMIT(1, limit), GFP_KERNEL_ACCOUNT);
+			if (ret < 0) {
+				kfree(ctx);
+				goto out;
+			}
+			WARN_ON(!ctx_id); /* can't happen */
+			rxfh.rss_context = ctx_id;
+		}
+	} else if (rxfh.rss_context) {
+		ctx = xa_load(&dev->ethtool->rss_ctx, rxfh.rss_context);
+		if (!ctx) {
+			ret = -ENOENT;
+			goto out;
+		}
+	}
 	rxfh_dev.hfunc = rxfh.hfunc;
 	rxfh_dev.rss_context = rxfh.rss_context;
 	rxfh_dev.input_xfrm = rxfh.input_xfrm;
 
-	ret = ops->set_rxfh(dev, &rxfh_dev, extack);
-	if (ret)
+	if (rxfh.rss_context && ops->create_rxfh_context) {
+		if (create)
+			ret = ops->create_rxfh_context(dev, ctx, &rxfh_dev,
+						       extack);
+		else if (rxfh_dev.rss_delete)
+			ret = ops->remove_rxfh_context(dev, ctx,
+						       rxfh.rss_context,
+						       extack);
+		else
+			ret = ops->modify_rxfh_context(dev, ctx, &rxfh_dev,
+						       extack);
+	} else {
+		ret = ops->set_rxfh(dev, &rxfh_dev, extack);
+	}
+	if (ret) {
+		if (create) {
+			/* failed to create, free our new tracking entry */
+			if (ops->create_rxfh_context)
+				xa_erase(&dev->ethtool->rss_ctx, rxfh.rss_context);
+			kfree(ctx);
+		}
 		goto out;
+	}
 
 	if (copy_to_user(useraddr + offsetof(struct ethtool_rxfh, rss_context),
 			 &rxfh_dev.rss_context, sizeof(rxfh_dev.rss_context)))
@@ -1396,8 +1480,44 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev,
 		else if (rxfh.indir_size != ETH_RXFH_INDIR_NO_CHANGE)
 			dev->priv_flags |= IFF_RXFH_CONFIGURED;
 	}
+	/* Update rss_ctx tracking */
+	if (create && !ops->create_rxfh_context) {
+		/* driver uses old API, it chose context ID */
+		if (WARN_ON(xa_load(&dev->ethtool->rss_ctx, rxfh.rss_context))) {
+			/* context ID reused, our tracking is screwed */
+			kfree(ctx);
+			goto out;
+		}
+		/* Allocate the exact ID the driver gave us */
+		if (xa_is_err(xa_store(&dev->ethtool->rss_ctx, rxfh.rss_context,
+				       ctx, GFP_KERNEL))) {
+			kfree(ctx);
+			goto out;
+		}
+	}
+	if (rxfh_dev.rss_delete) {
+		WARN_ON(xa_erase(&dev->ethtool->rss_ctx, rxfh.rss_context) != ctx);
+		kfree(ctx);
+	} else if (ctx) {
+		if (rxfh_dev.indir) {
+			for (i = 0; i < dev_indir_size; i++)
+				ethtool_rxfh_context_indir(ctx)[i] = rxfh_dev.indir[i];
+			ctx->indir_configured = 1;
+		}
+		if (rxfh_dev.key) {
+			memcpy(ethtool_rxfh_context_key(ctx), rxfh_dev.key,
+			       dev_key_size);
+			ctx->key_configured = 1;
+		}
+		if (rxfh_dev.hfunc != ETH_RSS_HASH_NO_CHANGE)
+			ctx->hfunc = rxfh_dev.hfunc;
+		if (rxfh_dev.input_xfrm != RXH_XFRM_NO_CHANGE)
+			ctx->input_xfrm = rxfh_dev.input_xfrm;
+	}
 
 out:
+	if (locked)
+		mutex_unlock(&dev->ethtool->rss_lock);
 	kfree(rss_config);
 	return ret;
 }
@@ -1509,7 +1629,7 @@ static int ethtool_set_wol(struct net_device *dev, char __user *useraddr)
 	if (ret)
 		return ret;
 
-	dev->wol_enabled = !!wol.wolopts;
+	dev->ethtool->wol_enabled = !!wol.wolopts;
 	ethtool_notify(dev, ETHTOOL_MSG_WOL_NTF, NULL);
 
 	return 0;