net: gro: expose GRO init/cleanup to use outside of NAPI

Make GRO init and cleanup functions global to be able to use GRO
without a NAPI instance. Taking into account already global gro_flush(),
it's now fully usable standalone.
New functions are not exported, since they're not supposed to be used
outside of the kernel core code.

Tested-by: Daniel Xu <dxu@dxuuu.xyz>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

3 files changed, 40 insertions, 34 deletions

diff --git a/include/net/gro.h b/include/net/gro.h
index 38d70c69ff80..22d3a69e4404 100644
--- a/include/net/gro.h
+++ b/include/net/gro.h
@@ -546,6 +546,9 @@ static inline void gro_normal_one(struct gro_node *gro, struct sk_buff *skb,
 		gro_normal_list(gro);
 }
 
+void gro_init(struct gro_node *gro);
+void gro_cleanup(struct gro_node *gro);
+
 /* This function is the alternative of 'inet_iif' and 'inet_sdif'
  * functions in case we can not rely on fields of IPCB.
  *
diff --git a/net/core/dev.c b/net/core/dev.c
index 634bfcb3b509..2dd9e6f490e6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6850,19 +6850,6 @@ static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
 	return HRTIMER_NORESTART;
 }
 
-static void init_gro_hash(struct napi_struct *napi)
-{
-	int i;
-
-	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
-		INIT_LIST_HEAD(&napi->gro.hash[i].list);
-		napi->gro.hash[i].count = 0;
-	}
-
-	napi->gro.bitmask = 0;
-	napi->gro.cached_napi_id = 0;
-}
-
 int dev_set_threaded(struct net_device *dev, bool threaded)
 {
 	struct napi_struct *napi;
@@ -7190,10 +7177,8 @@ void netif_napi_add_weight_locked(struct net_device *dev,
 	INIT_HLIST_NODE(&napi->napi_hash_node);
 	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
 	napi->timer.function = napi_watchdog;
-	init_gro_hash(napi);
+	gro_init(&napi->gro);
 	napi->skb = NULL;
-	INIT_LIST_HEAD(&napi->gro.rx_list);
-	napi->gro.rx_count = 0;
 	napi->poll = poll;
 	if (weight > NAPI_POLL_WEIGHT)
 		netdev_err_once(dev, "%s() called with weight %d\n", __func__,
@@ -7307,22 +7292,6 @@ void napi_enable(struct napi_struct *n)
 }
 EXPORT_SYMBOL(napi_enable);
 
-static void flush_gro_hash(struct napi_struct *napi)
-{
-	int i;
-
-	for (i = 0; i < GRO_HASH_BUCKETS; i++) {
-		struct sk_buff *skb, *n;
-
-		list_for_each_entry_safe(skb, n, &napi->gro.hash[i].list, list)
-			kfree_skb(skb);
-		napi->gro.hash[i].count = 0;
-	}
-
-	napi->gro.bitmask = 0;
-	napi->gro.cached_napi_id = 0;
-}
-
 /* Must be called in process context */
 void __netif_napi_del_locked(struct napi_struct *napi)
 {
@@ -7345,7 +7314,7 @@ void __netif_napi_del_locked(struct napi_struct *napi)
 	list_del_rcu(&napi->dev_list);
 	napi_free_frags(napi);
 
-	flush_gro_hash(napi);
+	gro_cleanup(&napi->gro);
 
 	if (napi->thread) {
 		kthread_stop(napi->thread);
@@ -12800,7 +12769,7 @@ static int __init net_dev_init(void)
 		INIT_CSD(&sd->defer_csd, trigger_rx_softirq, sd);
 		spin_lock_init(&sd->defer_lock);
 
-		init_gro_hash(&sd->backlog);
+		gro_init(&sd->backlog.gro);
 		sd->backlog.poll = process_backlog;
 		sd->backlog.weight = weight_p;
 		INIT_LIST_HEAD(&sd->backlog.poll_list);
diff --git a/net/core/gro.c b/net/core/gro.c
index 9e1803fdf249..19bd4cdaee3a 100644
--- a/net/core/gro.c
+++ b/net/core/gro.c
@@ -790,3 +790,37 @@ __sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
 	return sum;
 }
 EXPORT_SYMBOL(__skb_gro_checksum_complete);
+
+void gro_init(struct gro_node *gro)
+{
+	for (u32 i = 0; i < GRO_HASH_BUCKETS; i++) {
+		INIT_LIST_HEAD(&gro->hash[i].list);
+		gro->hash[i].count = 0;
+	}
+
+	gro->bitmask = 0;
+	gro->cached_napi_id = 0;
+
+	INIT_LIST_HEAD(&gro->rx_list);
+	gro->rx_count = 0;
+}
+
+void gro_cleanup(struct gro_node *gro)
+{
+	struct sk_buff *skb, *n;
+
+	for (u32 i = 0; i < GRO_HASH_BUCKETS; i++) {
+		list_for_each_entry_safe(skb, n, &gro->hash[i].list, list)
+			kfree_skb(skb);
+
+		gro->hash[i].count = 0;
+	}
+
+	gro->bitmask = 0;
+	gro->cached_napi_id = 0;
+
+	list_for_each_entry_safe(skb, n, &gro->rx_list, list)
+		kfree_skb(skb);
+
+	gro->rx_count = 0;
+}