From ff06bd191e722393d9abf7d6f9767f195274e909 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 15 Sep 2016 10:56:59 -0400 Subject: [PATCH] rpcrdma: RDMA/CM private message data structure Introduce data structure used by both client and server to exchange implementation details during RDMA/CM connection establishment. This is an experimental out-of-band exchange between Linux RPC-over-RDMA Version One implementations, replacing the deprecated CCP (see RFC 5666bis). The purpose of this extension is to enable prototyping of features that might be introduced in a subsequent version of RPC-over-RDMA. Suggested by Christoph Hellwig and Devesh Sharma. Signed-off-by: Chuck Lever Reviewed-by: Sagi Grimberg Signed-off-by: Anna Schumaker --- include/linux/sunrpc/rpc_rdma.h | 35 +++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/include/linux/sunrpc/rpc_rdma.h b/include/linux/sunrpc/rpc_rdma.h index 3b1ff38f0c37..a7da6bf56610 100644 --- a/include/linux/sunrpc/rpc_rdma.h +++ b/include/linux/sunrpc/rpc_rdma.h @@ -41,6 +41,7 @@ #define _LINUX_SUNRPC_RPC_RDMA_H #include +#include #define RPCRDMA_VERSION 1 #define rpcrdma_version cpu_to_be32(RPCRDMA_VERSION) @@ -129,4 +130,38 @@ enum rpcrdma_proc { #define rdma_done cpu_to_be32(RDMA_DONE) #define rdma_error cpu_to_be32(RDMA_ERROR) +/* + * Private extension to RPC-over-RDMA Version One. + * Message passed during RDMA-CM connection set-up. + * + * Add new fields at the end, and don't permute existing + * fields. + */ +struct rpcrdma_connect_private { + __be32 cp_magic; + u8 cp_version; + u8 cp_flags; + u8 cp_send_size; + u8 cp_recv_size; +} __packed; + +#define rpcrdma_cmp_magic __cpu_to_be32(0xf6ab0e18) + +enum { + RPCRDMA_CMP_VERSION = 1, + RPCRDMA_CMP_F_SND_W_INV_OK = BIT(0), +}; + +static inline u8 +rpcrdma_encode_buffer_size(unsigned int size) +{ + return (size >> 10) - 1; +} + +static inline unsigned int +rpcrdma_decode_buffer_size(u8 val) +{ + return ((unsigned int)val + 1) << 10; +} + #endif /* _LINUX_SUNRPC_RPC_RDMA_H */ -- 2.20.1