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 #include <linux/bitops.h>
45
46 #define RPCRDMA_VERSION 1
47 #define rpcrdma_version cpu_to_be32(RPCRDMA_VERSION)
48
49 enum {
50 RPCRDMA_V1_DEF_INLINE_SIZE = 1024,
51 };
52
53 struct rpcrdma_segment {
54 __be32 rs_handle; /* Registered memory handle */
55 __be32 rs_length; /* Length of the chunk in bytes */
56 __be64 rs_offset; /* Chunk virtual address or offset */
57 };
58
59 /*
60 * read chunk(s), encoded as a linked list.
61 */
62 struct rpcrdma_read_chunk {
63 __be32 rc_discrim; /* 1 indicates presence */
64 __be32 rc_position; /* Position in XDR stream */
65 struct rpcrdma_segment rc_target;
66 };
67
68 /*
69 * write chunk, and reply chunk.
70 */
71 struct rpcrdma_write_chunk {
72 struct rpcrdma_segment wc_target;
73 };
74
75 /*
76 * write chunk(s), encoded as a counted array.
77 */
78 struct rpcrdma_write_array {
79 __be32 wc_discrim; /* 1 indicates presence */
80 __be32 wc_nchunks; /* Array count */
81 struct rpcrdma_write_chunk wc_array[0];
82 };
83
84 struct rpcrdma_msg {
85 __be32 rm_xid; /* Mirrors the RPC header xid */
86 __be32 rm_vers; /* Version of this protocol */
87 __be32 rm_credit; /* Buffers requested/granted */
88 __be32 rm_type; /* Type of message (enum rpcrdma_proc) */
89 union {
90
91 struct { /* no chunks */
92 __be32 rm_empty[3]; /* 3 empty chunk lists */
93 } rm_nochunks;
94
95 struct { /* no chunks and padded */
96 __be32 rm_align; /* Padding alignment */
97 __be32 rm_thresh; /* Padding threshold */
98 __be32 rm_pempty[3]; /* 3 empty chunk lists */
99 } rm_padded;
100
101 struct {
102 __be32 rm_err;
103 __be32 rm_vers_low;
104 __be32 rm_vers_high;
105 } rm_error;
106
107 __be32 rm_chunks[0]; /* read, write and reply chunks */
108
109 } rm_body;
110 };
111
112 /*
113 * XDR sizes, in quads
114 */
115 enum {
116 rpcrdma_fixed_maxsz = 4,
117 rpcrdma_segment_maxsz = 4,
118 rpcrdma_readchunk_maxsz = 2 + rpcrdma_segment_maxsz,
119 };
120
121 /*
122 * Smallest RPC/RDMA header: rm_xid through rm_type, then rm_nochunks
123 */
124 #define RPCRDMA_HDRLEN_MIN (sizeof(__be32) * 7)
125 #define RPCRDMA_HDRLEN_ERR (sizeof(__be32) * 5)
126
127 enum rpcrdma_errcode {
128 ERR_VERS = 1,
129 ERR_CHUNK = 2
130 };
131
132 enum rpcrdma_proc {
133 RDMA_MSG = 0, /* An RPC call or reply msg */
134 RDMA_NOMSG = 1, /* An RPC call or reply msg - separate body */
135 RDMA_MSGP = 2, /* An RPC call or reply msg with padding */
136 RDMA_DONE = 3, /* Client signals reply completion */
137 RDMA_ERROR = 4 /* An RPC RDMA encoding error */
138 };
139
140 #define rdma_msg cpu_to_be32(RDMA_MSG)
141 #define rdma_nomsg cpu_to_be32(RDMA_NOMSG)
142 #define rdma_msgp cpu_to_be32(RDMA_MSGP)
143 #define rdma_done cpu_to_be32(RDMA_DONE)
144 #define rdma_error cpu_to_be32(RDMA_ERROR)
145
146 #define err_vers cpu_to_be32(ERR_VERS)
147 #define err_chunk cpu_to_be32(ERR_CHUNK)
148
149 /*
150 * Private extension to RPC-over-RDMA Version One.
151 * Message passed during RDMA-CM connection set-up.
152 *
153 * Add new fields at the end, and don't permute existing
154 * fields.
155 */
156 struct rpcrdma_connect_private {
157 __be32 cp_magic;
158 u8 cp_version;
159 u8 cp_flags;
160 u8 cp_send_size;
161 u8 cp_recv_size;
162 } __packed;
163
164 #define rpcrdma_cmp_magic __cpu_to_be32(0xf6ab0e18)
165
166 enum {
167 RPCRDMA_CMP_VERSION = 1,
168 RPCRDMA_CMP_F_SND_W_INV_OK = BIT(0),
169 };
170
171 static inline u8
rpcrdma_encode_buffer_size(unsigned int size)172 rpcrdma_encode_buffer_size(unsigned int size)
173 {
174 return (size >> 10) - 1;
175 }
176
177 static inline unsigned int
rpcrdma_decode_buffer_size(u8 val)178 rpcrdma_decode_buffer_size(u8 val)
179 {
180 return ((unsigned int)val + 1) << 10;
181 }
182
183 #endif /* _LINUX_SUNRPC_RPC_RDMA_H */
184