Return-Path: Received: from mail-it0-f67.google.com ([209.85.214.67]:33969 "EHLO mail-it0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbcHWRy3 (ORCPT ); Tue, 23 Aug 2016 13:54:29 -0400 Subject: [PATCH v2 15/22] rpcrdma: RDMA/CM private message data structure From: Chuck Lever To: linux-rdma@vger.kernel.org, linux-nfs@vger.kernel.org Date: Tue, 23 Aug 2016 13:54:06 -0400 Message-ID: <20160823175406.13038.79913.stgit@manet.1015granger.net> In-Reply-To: <20160823174402.13038.84561.stgit@manet.1015granger.net> References: <20160823174402.13038.84561.stgit@manet.1015granger.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Sender: linux-nfs-owner@vger.kernel.org List-ID: 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 --- 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 3b1ff38..a7da6bf 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 */