From 78476d315e190533757ab894255c4f2c2f254bce Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Fri, 29 Oct 2021 11:01:44 +0800 Subject: [PATCH] mctp: Add flow extension to skb This change adds a new skb extension for MCTP, to represent a request/response flow. The intention is to use this in a later change to allow i2c controllers to correctly configure a multiplexer over a flow. Since we have a cleanup function in the core path (if an extension is present), we'll need to make CONFIG_MCTP a bool, rather than a tristate. Includes a fix for a build warning with clang: Reported-by: kernel test robot Signed-off-by: Jeremy Kerr Signed-off-by: David S. Miller --- include/linux/skbuff.h | 3 +++ include/net/mctp.h | 7 +++++++ net/core/skbuff.c | 19 +++++++++++++++++++ net/mctp/Kconfig | 7 ++++++- 4 files changed, 35 insertions(+), 1 deletion(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index cb96f1e6460c..0bd6520329f6 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -4244,6 +4244,9 @@ enum skb_ext_id { #if IS_ENABLED(CONFIG_MPTCP) SKB_EXT_MPTCP, #endif +#if IS_ENABLED(CONFIG_MCTP_FLOWS) + SKB_EXT_MCTP, +#endif SKB_EXT_NUM, /* must be last */ }; diff --git a/include/net/mctp.h b/include/net/mctp.h index 23bec708f4c7..7a5ba801703c 100644 --- a/include/net/mctp.h +++ b/include/net/mctp.h @@ -189,6 +189,13 @@ static inline struct mctp_skb_cb *mctp_cb(struct sk_buff *skb) return (void *)(skb->cb); } +/* If CONFIG_MCTP_FLOWS, we may add one of these as a SKB extension, + * indicating the flow to the device driver. + */ +struct mctp_flow { + struct mctp_sk_key *key; +}; + /* Route definition. * * These are held in the pernet->mctp.routes list, with RCU protection for diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 09b8cf8ab234..67a9188d8a49 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -70,6 +70,7 @@ #include #include #include +#include #include #include @@ -4440,6 +4441,9 @@ static const u8 skb_ext_type_len[] = { #if IS_ENABLED(CONFIG_MPTCP) [SKB_EXT_MPTCP] = SKB_EXT_CHUNKSIZEOF(struct mptcp_ext), #endif +#if IS_ENABLED(CONFIG_MCTP_FLOWS) + [SKB_EXT_MCTP] = SKB_EXT_CHUNKSIZEOF(struct mctp_flow), +#endif }; static __always_inline unsigned int skb_ext_total_length(void) @@ -4457,6 +4461,9 @@ static __always_inline unsigned int skb_ext_total_length(void) #if IS_ENABLED(CONFIG_MPTCP) skb_ext_type_len[SKB_EXT_MPTCP] + #endif +#if IS_ENABLED(CONFIG_MCTP_FLOWS) + skb_ext_type_len[SKB_EXT_MCTP] + +#endif 0; } @@ -6529,6 +6536,14 @@ static void skb_ext_put_sp(struct sec_path *sp) } #endif +#ifdef CONFIG_MCTP_FLOWS +static void skb_ext_put_mctp(struct mctp_flow *flow) +{ + if (flow->key) + mctp_key_unref(flow->key); +} +#endif + void __skb_ext_del(struct sk_buff *skb, enum skb_ext_id id) { struct skb_ext *ext = skb->extensions; @@ -6564,6 +6579,10 @@ free_now: if (__skb_ext_exist(ext, SKB_EXT_SEC_PATH)) skb_ext_put_sp(skb_ext_get_ptr(ext, SKB_EXT_SEC_PATH)); #endif +#ifdef CONFIG_MCTP_FLOWS + if (__skb_ext_exist(ext, SKB_EXT_MCTP)) + skb_ext_put_mctp(skb_ext_get_ptr(ext, SKB_EXT_MCTP)); +#endif kmem_cache_free(skbuff_ext_cache, ext); } diff --git a/net/mctp/Kconfig b/net/mctp/Kconfig index 868c92272cbd..3a5c0e70da77 100644 --- a/net/mctp/Kconfig +++ b/net/mctp/Kconfig @@ -1,7 +1,7 @@ menuconfig MCTP depends on NET - tristate "MCTP core protocol support" + bool "MCTP core protocol support" help Management Component Transport Protocol (MCTP) is an in-system protocol for communicating between management controllers and @@ -16,3 +16,8 @@ config MCTP_TEST bool "MCTP core tests" if !KUNIT_ALL_TESTS depends on MCTP=y && KUNIT=y default KUNIT_ALL_TESTS + +config MCTP_FLOWS + bool + depends on MCTP + select SKB_EXTENSIONS -- 2.11.0