diff options
Diffstat (limited to 'include/net/mptcp.h')
-rw-r--r-- | include/net/mptcp.h | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/include/net/mptcp.h b/include/net/mptcp.h new file mode 100644 index 000000000000..0573ae75c3db --- /dev/null +++ b/include/net/mptcp.h @@ -0,0 +1,85 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Multipath TCP + * + * Copyright (c) 2017 - 2019, Intel Corporation. + */ + +#ifndef __NET_MPTCP_H +#define __NET_MPTCP_H + +#include <linux/skbuff.h> +#include <linux/types.h> + +/* MPTCP sk_buff extension data */ +struct mptcp_ext { + u64 data_ack; + u64 data_seq; + u32 subflow_seq; + u16 data_len; + u8 use_map:1, + dsn64:1, + data_fin:1, + use_ack:1, + ack64:1, + __unused:3; + /* one byte hole */ +}; + +#ifdef CONFIG_MPTCP + +/* move the skb extension owership, with the assumption that 'to' is + * newly allocated + */ +static inline void mptcp_skb_ext_move(struct sk_buff *to, + struct sk_buff *from) +{ + if (!skb_ext_exist(from, SKB_EXT_MPTCP)) + return; + + if (WARN_ON_ONCE(to->active_extensions)) + skb_ext_put(to); + + to->active_extensions = from->active_extensions; + to->extensions = from->extensions; + from->active_extensions = 0; +} + +static inline bool mptcp_ext_matches(const struct mptcp_ext *to_ext, + const struct mptcp_ext *from_ext) +{ + /* MPTCP always clears the ext when adding it to the skb, so + * holes do not bother us here + */ + return !from_ext || + (to_ext && from_ext && + !memcmp(from_ext, to_ext, sizeof(struct mptcp_ext))); +} + +/* check if skbs can be collapsed. + * MPTCP collapse is allowed if neither @to or @from carry an mptcp data + * mapping, or if the extension of @to is the same as @from. + * Collapsing is not possible if @to lacks an extension, but @from carries one. + */ +static inline bool mptcp_skb_can_collapse(const struct sk_buff *to, + const struct sk_buff *from) +{ + return mptcp_ext_matches(skb_ext_find(to, SKB_EXT_MPTCP), + skb_ext_find(from, SKB_EXT_MPTCP)); +} + +#else + +static inline void mptcp_skb_ext_move(struct sk_buff *to, + const struct sk_buff *from) +{ +} + +static inline bool mptcp_skb_can_collapse(const struct sk_buff *to, + const struct sk_buff *from) +{ + return true; +} + +#endif /* CONFIG_MPTCP */ +#endif /* __NET_MPTCP_H */ |