summaryrefslogtreecommitdiff
path: root/include/linux/sunrpc/rpc_rdma.h
blob: 245fc59b73247d744682c128bfcae1270e146c26 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
/*
 * Copyright (c) 2003-2007 Network Appliance, Inc. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the BSD-type
 * license below:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *      Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *      Redistributions in binary form must reproduce the above
 *      copyright notice, this list of conditions and the following
 *      disclaimer in the documentation and/or other materials provided
 *      with the distribution.
 *
 *      Neither the name of the Network Appliance, Inc. nor the names of
 *      its contributors may be used to endorse or promote products
 *      derived from this software without specific prior written
 *      permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef _LINUX_SUNRPC_RPC_RDMA_H
#define _LINUX_SUNRPC_RPC_RDMA_H

#include <linux/types.h>
#include <linux/bitops.h>

#define RPCRDMA_VERSION		1
#define rpcrdma_version		cpu_to_be32(RPCRDMA_VERSION)

enum {
	RPCRDMA_V1_DEF_INLINE_SIZE	= 1024,
};

struct rpcrdma_segment {
	__be32 rs_handle;	/* Registered memory handle */
	__be32 rs_length;	/* Length of the chunk in bytes */
	__be64 rs_offset;	/* Chunk virtual address or offset */
};

/*
 * read chunk(s), encoded as a linked list.
 */
struct rpcrdma_read_chunk {
	__be32 rc_discrim;	/* 1 indicates presence */
	__be32 rc_position;	/* Position in XDR stream */
	struct rpcrdma_segment rc_target;
};

/*
 * write chunk, and reply chunk.
 */
struct rpcrdma_write_chunk {
	struct rpcrdma_segment wc_target;
};

/*
 * write chunk(s), encoded as a counted array.
 */
struct rpcrdma_write_array {
	__be32 wc_discrim;	/* 1 indicates presence */
	__be32 wc_nchunks;	/* Array count */
	struct rpcrdma_write_chunk wc_array[0];
};

struct rpcrdma_msg {
	__be32 rm_xid;	/* Mirrors the RPC header xid */
	__be32 rm_vers;	/* Version of this protocol */
	__be32 rm_credit;	/* Buffers requested/granted */
	__be32 rm_type;	/* Type of message (enum rpcrdma_proc) */
	union {

		struct {			/* no chunks */
			__be32 rm_empty[3];	/* 3 empty chunk lists */
		} rm_nochunks;

		struct {			/* no chunks and padded */
			__be32 rm_align;	/* Padding alignment */
			__be32 rm_thresh;	/* Padding threshold */
			__be32 rm_pempty[3];	/* 3 empty chunk lists */
		} rm_padded;

		struct {
			__be32 rm_err;
			__be32 rm_vers_low;
			__be32 rm_vers_high;
		} rm_error;

		__be32 rm_chunks[0];	/* read, write and reply chunks */

	} rm_body;
};

/*
 * XDR sizes, in quads
 */
enum {
	rpcrdma_fixed_maxsz	= 4,
	rpcrdma_segment_maxsz	= 4,
	rpcrdma_readchunk_maxsz	= 2 + rpcrdma_segment_maxsz,
};

/*
 * Smallest RPC/RDMA header: rm_xid through rm_type, then rm_nochunks
 */
#define RPCRDMA_HDRLEN_MIN	(sizeof(__be32) * 7)
#define RPCRDMA_HDRLEN_ERR	(sizeof(__be32) * 5)

enum rpcrdma_errcode {
	ERR_VERS = 1,
	ERR_CHUNK = 2
};

enum rpcrdma_proc {
	RDMA_MSG = 0,		/* An RPC call or reply msg */
	RDMA_NOMSG = 1,		/* An RPC call or reply msg - separate body */
	RDMA_MSGP = 2,		/* An RPC call or reply msg with padding */
	RDMA_DONE = 3,		/* Client signals reply completion */
	RDMA_ERROR = 4		/* An RPC RDMA encoding error */
};

#define rdma_msg	cpu_to_be32(RDMA_MSG)
#define rdma_nomsg	cpu_to_be32(RDMA_NOMSG)
#define rdma_msgp	cpu_to_be32(RDMA_MSGP)
#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 */