include/linux/sunrpc/rpc_rdma.h

   1 /*
   2  * Copyright (c) 2015-2017 Oracle. All rights reserved.
   3  * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the BSD-type
   9  * license below:
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  *
  15  *      Redistributions of source code must retain the above copyright
  16  *      notice, this list of conditions and the following disclaimer.
  17  *
  18  *      Redistributions in binary form must reproduce the above
  19  *      copyright notice, this list of conditions and the following
  20  *      disclaimer in the documentation and/or other materials provided
  21  *      with the distribution.
  22  *
  23  *      Neither the name of the Network Appliance, Inc. nor the names of
  24  *      its contributors may be used to endorse or promote products
  25  *      derived from this software without specific prior written
  26  *      permission.
  27  *
  28  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  29  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  30  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  31  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  32  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  33  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  34  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  35  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  36  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  37  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  38  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  39  */
  40
  41 #ifndef _LINUX_SUNRPC_RPC_RDMA_H
  42 #define _LINUX_SUNRPC_RPC_RDMA_H
  43
  44 #include <linux/types.h>
  45 #include <linux/bitops.h>
  46
  47 #define RPCRDMA_VERSION         1
  48 #define rpcrdma_version         cpu_to_be32(RPCRDMA_VERSION)
  49
  50 enum {
  51         RPCRDMA_V1_DEF_INLINE_SIZE      = 1024,
  52 };
  53
  54 /*
  55  * XDR sizes, in quads
  56  */
  57 enum {
  58         rpcrdma_fixed_maxsz     = 4,
  59         rpcrdma_segment_maxsz   = 4,
  60         rpcrdma_readchunk_maxsz = 2 + rpcrdma_segment_maxsz,
  61 };
  62
  63 /*
  64  * Smallest RPC/RDMA header: rm_xid through rm_type, then rm_nochunks
  65  */
  66 #define RPCRDMA_HDRLEN_MIN      (sizeof(__be32) * 7)
  67 #define RPCRDMA_HDRLEN_ERR      (sizeof(__be32) * 5)
  68
  69 enum rpcrdma_errcode {
  70         ERR_VERS = 1,
  71         ERR_CHUNK = 2
  72 };
  73
  74 enum rpcrdma_proc {
  75         RDMA_MSG = 0,           /* An RPC call or reply msg */
  76         RDMA_NOMSG = 1,         /* An RPC call or reply msg - separate body */
  77         RDMA_MSGP = 2,          /* An RPC call or reply msg with padding */
  78         RDMA_DONE = 3,          /* Client signals reply completion */
  79         RDMA_ERROR = 4          /* An RPC RDMA encoding error */
  80 };
  81
  82 #define rdma_msg        cpu_to_be32(RDMA_MSG)
  83 #define rdma_nomsg      cpu_to_be32(RDMA_NOMSG)
  84 #define rdma_msgp       cpu_to_be32(RDMA_MSGP)
  85 #define rdma_done       cpu_to_be32(RDMA_DONE)
  86 #define rdma_error      cpu_to_be32(RDMA_ERROR)
  87
  88 #define err_vers        cpu_to_be32(ERR_VERS)
  89 #define err_chunk       cpu_to_be32(ERR_CHUNK)
  90
  91 /*
  92  * Private extension to RPC-over-RDMA Version One.
  93  * Message passed during RDMA-CM connection set-up.
  94  *
  95  * Add new fields at the end, and don't permute existing
  96  * fields.
  97  */
  98 struct rpcrdma_connect_private {
  99         __be32                  cp_magic;
 100         u8                      cp_version;
 101         u8                      cp_flags;
 102         u8                      cp_send_size;
 103         u8                      cp_recv_size;
 104 } __packed;
 105
 106 #define rpcrdma_cmp_magic       __cpu_to_be32(0xf6ab0e18)
 107
 108 enum {
 109         RPCRDMA_CMP_VERSION             = 1,
 110         RPCRDMA_CMP_F_SND_W_INV_OK      = BIT(0),
 111 };
 112
 113 static inline u8
 114 rpcrdma_encode_buffer_size(unsigned int size)
 115 {
 116         return (size >> 10) - 1;
 117 }
 118
 119 static inline unsigned int
 120 rpcrdma_decode_buffer_size(u8 val)
 121 {
 122         return ((unsigned int)val + 1) << 10;
 123 }
 124
 125 #endif                          /* _LINUX_SUNRPC_RPC_RDMA_H */