LXR linux/include/linux/sunrpc/rpc

   1/*
   2 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
   3 *
   4 * This software is available to you under a choice of one of two
   5 * licenses.  You may choose to be licensed under the terms of the GNU
   6 * General Public License (GPL) Version 2, available from the file
   7 * COPYING in the main directory of this source tree, or the BSD-type
   8 * license below:
   9 *
  10 * Redistribution and use in source and binary forms, with or without
  11 * modification, are permitted provided that the following conditions
  12 * are met:
  13 *
  14 *      Redistributions of source code must retain the above copyright
  15 *      notice, this list of conditions and the following disclaimer.
  16 *
  17 *      Redistributions in binary form must reproduce the above
  18 *      copyright notice, this list of conditions and the following
  19 *      disclaimer in the documentation and/or other materials provided
  20 *      with the distribution.
  21 *
  22 *      Neither the name of the Network Appliance, Inc. nor the names of
  23 *      its contributors may be used to endorse or promote products
  24 *      derived from this software without specific prior written
  25 *      permission.
  26 *
  27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  30 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  31 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  32 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  33 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  34 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  35 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  36 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  37 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  38 */
  39
  40#ifndef _LINUX_SUNRPC_RPC_RDMA_H
  41#define _LINUX_SUNRPC_RPC_RDMA_H
  42
  43#include <linux/types.h>
  44
  45#define RPCRDMA_VERSION         1
  46#define rpcrdma_version         cpu_to_be32(RPCRDMA_VERSION)
  47
  48struct rpcrdma_segment {
  49        __be32 rs_handle;       /* Registered memory handle */
  50        __be32 rs_length;       /* Length of the chunk in bytes */
  51        __be64 rs_offset;       /* Chunk virtual address or offset */
  52};
  53
  54/*
  55 * read chunk(s), encoded as a linked list.
  56 */
  57struct rpcrdma_read_chunk {
  58        __be32 rc_discrim;      /* 1 indicates presence */
  59        __be32 rc_position;     /* Position in XDR stream */
  60        struct rpcrdma_segment rc_target;
  61};
  62
  63/*
  64 * write chunk, and reply chunk.
  65 */
  66struct rpcrdma_write_chunk {
  67        struct rpcrdma_segment wc_target;
  68};
  69
  70/*
  71 * write chunk(s), encoded as a counted array.
  72 */
  73struct rpcrdma_write_array {
  74        __be32 wc_discrim;      /* 1 indicates presence */
  75        __be32 wc_nchunks;      /* Array count */
  76        struct rpcrdma_write_chunk wc_array[0];
  77};
  78
  79struct rpcrdma_msg {
  80        __be32 rm_xid;  /* Mirrors the RPC header xid */
  81        __be32 rm_vers; /* Version of this protocol */
  82        __be32 rm_credit;       /* Buffers requested/granted */
  83        __be32 rm_type; /* Type of message (enum rpcrdma_proc) */
  84        union {
  85
  86                struct {                        /* no chunks */
  87                        __be32 rm_empty[3];     /* 3 empty chunk lists */
  88                } rm_nochunks;
  89
  90                struct {                        /* no chunks and padded */
  91                        __be32 rm_align;        /* Padding alignment */
  92                        __be32 rm_thresh;       /* Padding threshold */
  93                        __be32 rm_pempty[3];    /* 3 empty chunk lists */
  94                } rm_padded;
  95
  96                struct {
  97                        __be32 rm_err;
  98                        __be32 rm_vers_low;
  99                        __be32 rm_vers_high;
 100                } rm_error;
 101
 102                __be32 rm_chunks[0];    /* read, write and reply chunks */
 103
 104        } rm_body;
 105};
 106
 107/*
 108 * Smallest RPC/RDMA header: rm_xid through rm_type, then rm_nochunks
 109 */
 110#define RPCRDMA_HDRLEN_MIN      (sizeof(__be32) * 7)
 111#define RPCRDMA_HDRLEN_ERR      (sizeof(__be32) * 5)
 112
 113enum rpcrdma_errcode {
 114        ERR_VERS = 1,
 115        ERR_CHUNK = 2
 116};
 117
 118enum rpcrdma_proc {
 119        RDMA_MSG = 0,           /* An RPC call or reply msg */
 120        RDMA_NOMSG = 1,         /* An RPC call or reply msg - separate body */
 121        RDMA_MSGP = 2,          /* An RPC call or reply msg with padding */
 122        RDMA_DONE = 3,          /* Client signals reply completion */
 123        RDMA_ERROR = 4          /* An RPC RDMA encoding error */
 124};
 125
 126#define rdma_msg        cpu_to_be32(RDMA_MSG)
 127#define rdma_nomsg      cpu_to_be32(RDMA_NOMSG)
 128#define rdma_msgp       cpu_to_be32(RDMA_MSGP)
 129#define rdma_done       cpu_to_be32(RDMA_DONE)
 130#define rdma_error      cpu_to_be32(RDMA_ERROR)
 131
 132#endif                          /* _LINUX_SUNRPC_RPC_RDMA_H */
 133