From 81fd11a61df78837b50f429a7b9e6be94b973b38 Mon Sep 17 00:00:00 2001
From: Geliang Tang <geliang.tang@suse.com>
Date: Wed, 23 Aug 2023 19:04:46 +0800
Subject: [PATCH] mptcp: add bpf_burst set/get params

This patch implements the set/get params interfaces for bpf_burst
scheduler.

Export bpf_sk_storage_lookup(), use it to get bpf_local_storage_data
from sk->sk_bpf_storage, then get or set its params ptr->snd_burst.

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 include/net/bpf_sk_storage.h |  7 +++++++
 net/core/bpf_sk_storage.c    |  2 +-
 net/mptcp/sched.c            | 39 ++++++++++++++++++++++++++++++++++++
 3 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/include/net/bpf_sk_storage.h b/include/net/bpf_sk_storage.h
index 2926f1f00d656a..805142d59d0232 100644
--- a/include/net/bpf_sk_storage.h
+++ b/include/net/bpf_sk_storage.h
@@ -37,6 +37,8 @@ int bpf_sk_storage_diag_put(struct bpf_sk_storage_diag *diag,
 			    struct sock *sk, struct sk_buff *skb,
 			    int stg_array_type,
 			    unsigned int *res_diag_size);
+struct bpf_local_storage_data *
+bpf_sk_storage_lookup(struct sock *sk, struct bpf_map *map, bool cacheit_lockit);
 #else
 static inline int bpf_sk_storage_clone(const struct sock *sk,
 				       struct sock *newsk)
@@ -58,6 +60,11 @@ static inline int bpf_sk_storage_diag_put(struct bpf_sk_storage_diag *diag,
 {
 	return 0;
 }
+struct bpf_local_storage_data *
+bpf_sk_storage_lookup(struct sock *sk, struct bpf_map *map, bool cacheit_lockit)
+{
+	return NULL;
+}
 #endif
 
 #endif /* _BPF_SK_STORAGE_H */
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index cca7594be92ec6..1c023f65017f54 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -17,7 +17,7 @@
 
 DEFINE_BPF_STORAGE_CACHE(sk_cache);
 
-static struct bpf_local_storage_data *
+struct bpf_local_storage_data *
 bpf_sk_storage_lookup(struct sock *sk, struct bpf_map *map, bool cacheit_lockit)
 {
 	struct bpf_local_storage *sk_storage;
diff --git a/net/mptcp/sched.c b/net/mptcp/sched.c
index c78ed61290d2ea..067df28899a672 100644
--- a/net/mptcp/sched.c
+++ b/net/mptcp/sched.c
@@ -11,6 +11,7 @@
 #include <linux/list.h>
 #include <linux/rculist.h>
 #include <linux/spinlock.h>
+#include <net/bpf_sk_storage.h>
 #include "protocol.h"
 
 static DEFINE_SPINLOCK(mptcp_sched_list_lock);
@@ -202,18 +203,56 @@ mptcp_subflow_ctx_by_pos(const struct mptcp_sched_data *data, unsigned int pos)
 
 int mptcp_sched_get_params(struct mptcp_sock *msk)
 {
+	struct sock *sk = (struct sock *)msk;
+
 	if (msk->sched == &mptcp_sched_default)
 		return msk->snd_burst;
 
+	if (sk->sk_bpf_storage && sk->sk_bpf_storage->smap &&
+	    !strcmp(sk->sk_bpf_storage->smap->map.name, "mptcp_burst_map")) {
+		struct bpf_local_storage_data *sdata;
+
+		sdata = bpf_sk_storage_lookup(sk, &sk->sk_bpf_storage->smap->map, true);
+		if (sdata) {
+			struct mptcp_burst_storage {
+				int snd_burst;
+			} *ptr;
+
+			ptr = (struct mptcp_burst_storage *)sdata->data;
+			if (ptr)
+				return ptr->snd_burst;
+		}
+	}
+
 	return 0;
 }
 
 int mptcp_sched_set_params(struct mptcp_sock *msk, int burst)
 {
+	struct sock *sk = (struct sock *)msk;
+
 	if (msk->sched == &mptcp_sched_default) {
 		msk->snd_burst = burst;
 		return 0;
 	}
 
+	if (sk->sk_bpf_storage && sk->sk_bpf_storage->smap &&
+	    !strcmp(sk->sk_bpf_storage->smap->map.name, "mptcp_burst_map")) {
+		struct bpf_local_storage_data *sdata;
+
+		sdata = bpf_sk_storage_lookup(sk, &sk->sk_bpf_storage->smap->map, true);
+		if (sdata) {
+			struct mptcp_burst_storage {
+				int snd_burst;
+			} *ptr;
+
+			ptr = (struct mptcp_burst_storage *)sdata->data;
+			if (ptr) {
+				ptr->snd_burst = burst;
+				return 0;
+			}
+		}
+	}
+
 	return 0;
 }