xref: /linux/net/smc/smc_clc.h (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  CLC (connection layer control) handshake over initial TCP socket to
6  *  prepare for RDMA traffic
7  *
8  *  Copyright IBM Corp. 2016
9  *
10  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
11  */
12 
13 #ifndef _SMC_CLC_H
14 #define _SMC_CLC_H
15 
16 #include <rdma/ib_verbs.h>
17 
18 #include "smc.h"
19 
20 #define SMC_CLC_PROPOSAL	0x01
21 #define SMC_CLC_ACCEPT		0x02
22 #define SMC_CLC_CONFIRM		0x03
23 #define SMC_CLC_DECLINE		0x04
24 
25 /* eye catcher "SMCR" EBCDIC for CLC messages */
26 static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
27 
28 #define SMC_CLC_V1		0x1		/* SMC version                */
29 #define CLC_WAIT_TIME		(6 * HZ)	/* max. wait time on clcsock  */
30 #define SMC_CLC_DECL_MEM	0x01010000  /* insufficient memory resources  */
31 #define SMC_CLC_DECL_TIMEOUT	0x02000000  /* timeout                        */
32 #define SMC_CLC_DECL_CNFERR	0x03000000  /* configuration error            */
33 #define SMC_CLC_DECL_IPSEC	0x03030000  /* IPsec usage                    */
34 #define SMC_CLC_DECL_SYNCERR	0x04000000  /* synchronization error          */
35 #define SMC_CLC_DECL_REPLY	0x06000000  /* reply to a received decline    */
36 #define SMC_CLC_DECL_INTERR	0x99990000  /* internal error                 */
37 #define SMC_CLC_DECL_TCL	0x02040000  /* timeout w4 QP confirm          */
38 #define SMC_CLC_DECL_SEND	0x07000000  /* sending problem                */
39 
40 struct smc_clc_msg_hdr {	/* header1 of clc messages */
41 	u8 eyecatcher[4];	/* eye catcher */
42 	u8 type;		/* proposal / accept / confirm / decline */
43 	__be16 length;
44 #if defined(__BIG_ENDIAN_BITFIELD)
45 	u8 version : 4,
46 	   flag    : 1,
47 	   rsvd	   : 3;
48 #elif defined(__LITTLE_ENDIAN_BITFIELD)
49 	u8 rsvd    : 3,
50 	   flag    : 1,
51 	   version : 4;
52 #endif
53 } __packed;			/* format defined in RFC7609 */
54 
55 struct smc_clc_msg_trail {	/* trailer of clc messages */
56 	u8 eyecatcher[4];
57 };
58 
59 struct smc_clc_msg_local {	/* header2 of clc messages */
60 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
61 	u8 gid[16];		/* gid of ib_device port */
62 	u8 mac[6];		/* mac of ib_device port */
63 };
64 
65 struct smc_clc_msg_proposal {	/* clc proposal message */
66 	struct smc_clc_msg_hdr hdr;
67 	struct smc_clc_msg_local lcl;
68 	__be16 iparea_offset;	/* offset to IP address information area */
69 	__be32 outgoing_subnet;	/* subnet mask */
70 	u8 prefix_len;		/* number of significant bits in mask */
71 	u8 reserved[2];
72 	u8 ipv6_prefixes_cnt;	/* number of IPv6 prefixes in prefix array */
73 	struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
74 } __aligned(4);
75 
76 struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
77 	struct smc_clc_msg_hdr hdr;
78 	struct smc_clc_msg_local lcl;
79 	u8 qpn[3];		/* QP number */
80 	__be32 rmb_rkey;	/* RMB rkey */
81 	u8 conn_idx;		/* Connection index, which RMBE in RMB */
82 	__be32 rmbe_alert_token;/* unique connection id */
83 #if defined(__BIG_ENDIAN_BITFIELD)
84 	u8 rmbe_size : 4,	/* RMBE buf size (compressed notation) */
85 	   qp_mtu   : 4;	/* QP mtu */
86 #elif defined(__LITTLE_ENDIAN_BITFIELD)
87 	u8 qp_mtu   : 4,
88 	   rmbe_size : 4;
89 #endif
90 	u8 reserved;
91 	__be64 rmb_dma_addr;	/* RMB virtual address */
92 	u8 reserved2;
93 	u8 psn[3];		/* initial packet sequence number */
94 	struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
95 } __packed;			/* format defined in RFC7609 */
96 
97 struct smc_clc_msg_decline {	/* clc decline message */
98 	struct smc_clc_msg_hdr hdr;
99 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
100 	__be32 peer_diagnosis;	/* diagnosis information */
101 	u8 reserved2[4];
102 	struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
103 } __aligned(4);
104 
105 struct smc_sock;
106 struct smc_ib_device;
107 
108 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
109 		     u8 expected_type);
110 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
111 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_ib_device *smcibdev,
112 			  u8 ibport);
113 int smc_clc_send_confirm(struct smc_sock *smc);
114 int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);
115 
116 #endif
117