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 #define SMC_CLC_V1 0x1 /* SMC version */
26 #define SMC_TYPE_R 0 /* SMC-R only */
27 #define SMC_TYPE_D 1 /* SMC-D only */
28 #define SMC_TYPE_B 3 /* SMC-R and SMC-D */
29 #define CLC_WAIT_TIME (6 * HZ) /* max. wait time on clcsock */
30 #define CLC_WAIT_TIME_SHORT HZ /* short wait time on clcsock */
31 #define SMC_CLC_DECL_MEM 0x01010000 /* insufficient memory resources */
32 #define SMC_CLC_DECL_TIMEOUT_CL 0x02010000 /* timeout w4 QP confirm link */
33 #define SMC_CLC_DECL_TIMEOUT_AL 0x02020000 /* timeout w4 QP add link */
34 #define SMC_CLC_DECL_CNFERR 0x03000000 /* configuration error */
35 #define SMC_CLC_DECL_PEERNOSMC 0x03010000 /* peer did not indicate SMC */
36 #define SMC_CLC_DECL_IPSEC 0x03020000 /* IPsec usage */
37 #define SMC_CLC_DECL_NOSMCDEV 0x03030000 /* no SMC device found (R or D) */
38 #define SMC_CLC_DECL_NOSMCDDEV 0x03030001 /* no SMC-D device found */
39 #define SMC_CLC_DECL_NOSMCRDEV 0x03030002 /* no SMC-R device found */
40 #define SMC_CLC_DECL_SMCDNOTALK 0x03030003 /* SMC-D dev can't talk to peer */
41 #define SMC_CLC_DECL_MODEUNSUPP 0x03040000 /* smc modes do not match (R or D)*/
42 #define SMC_CLC_DECL_RMBE_EC 0x03050000 /* peer has eyecatcher in RMBE */
43 #define SMC_CLC_DECL_OPTUNSUPP 0x03060000 /* fastopen sockopt not supported */
44 #define SMC_CLC_DECL_DIFFPREFIX 0x03070000 /* IP prefix / subnet mismatch */
45 #define SMC_CLC_DECL_GETVLANERR 0x03080000 /* err to get vlan id of ip device*/
46 #define SMC_CLC_DECL_ISMVLANERR 0x03090000 /* err to reg vlan id on ism dev */
47 #define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */
48 #define SMC_CLC_DECL_PEERDECL 0x05000000 /* peer declined during handshake */
49 #define SMC_CLC_DECL_INTERR 0x09990000 /* internal error */
50 #define SMC_CLC_DECL_ERR_RTOK 0x09990001 /* rtoken handling failed */
51 #define SMC_CLC_DECL_ERR_RDYLNK 0x09990002 /* ib ready link failed */
52 #define SMC_CLC_DECL_ERR_REGRMB 0x09990003 /* reg rmb failed */
53
54 struct smc_clc_msg_hdr { /* header1 of clc messages */
55 u8 eyecatcher[4]; /* eye catcher */
56 u8 type; /* proposal / accept / confirm / decline */
57 __be16 length;
58 #if defined(__BIG_ENDIAN_BITFIELD)
59 u8 version : 4,
60 flag : 1,
61 rsvd : 1,
62 path : 2;
63 #elif defined(__LITTLE_ENDIAN_BITFIELD)
64 u8 path : 2,
65 rsvd : 1,
66 flag : 1,
67 version : 4;
68 #endif
69 } __packed; /* format defined in RFC7609 */
70
71 struct smc_clc_msg_trail { /* trailer of clc messages */
72 u8 eyecatcher[4];
73 };
74
75 struct smc_clc_msg_local { /* header2 of clc messages */
76 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
77 u8 gid[16]; /* gid of ib_device port */
78 u8 mac[6]; /* mac of ib_device port */
79 };
80
81 #define SMC_CLC_MAX_V6_PREFIX 8
82
83 /* Struct would be 4 byte aligned, but it is used in an array that is sent
84 * to peers and must conform to RFC7609, hence we need to use packed here.
85 */
86 struct smc_clc_ipv6_prefix {
87 struct in6_addr prefix;
88 u8 prefix_len;
89 } __packed; /* format defined in RFC7609 */
90
91 struct smc_clc_msg_proposal_prefix { /* prefix part of clc proposal message*/
92 __be32 outgoing_subnet; /* subnet mask */
93 u8 prefix_len; /* number of significant bits in mask */
94 u8 reserved[2];
95 u8 ipv6_prefixes_cnt; /* number of IPv6 prefixes in prefix array */
96 } __aligned(4);
97
98 struct smc_clc_msg_smcd { /* SMC-D GID information */
99 u64 gid; /* ISM GID of requestor */
100 u8 res[32];
101 };
102
103 struct smc_clc_msg_proposal { /* clc proposal message sent by Linux */
104 struct smc_clc_msg_hdr hdr;
105 struct smc_clc_msg_local lcl;
106 __be16 iparea_offset; /* offset to IP address information area */
107 } __aligned(4);
108
109 #define SMC_CLC_PROPOSAL_MAX_OFFSET 0x28
110 #define SMC_CLC_PROPOSAL_MAX_PREFIX (SMC_CLC_MAX_V6_PREFIX * \
111 sizeof(struct smc_clc_ipv6_prefix))
112 #define SMC_CLC_MAX_LEN (sizeof(struct smc_clc_msg_proposal) + \
113 SMC_CLC_PROPOSAL_MAX_OFFSET + \
114 sizeof(struct smc_clc_msg_proposal_prefix) + \
115 SMC_CLC_PROPOSAL_MAX_PREFIX + \
116 sizeof(struct smc_clc_msg_trail))
117
118 struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
119 struct smc_clc_msg_hdr hdr;
120 union {
121 struct { /* SMC-R */
122 struct smc_clc_msg_local lcl;
123 u8 qpn[3]; /* QP number */
124 __be32 rmb_rkey; /* RMB rkey */
125 u8 rmbe_idx; /* Index of RMBE in RMB */
126 __be32 rmbe_alert_token;/* unique connection id */
127 #if defined(__BIG_ENDIAN_BITFIELD)
128 u8 rmbe_size : 4, /* buf size (compressed) */
129 qp_mtu : 4; /* QP mtu */
130 #elif defined(__LITTLE_ENDIAN_BITFIELD)
131 u8 qp_mtu : 4,
132 rmbe_size : 4;
133 #endif
134 u8 reserved;
135 __be64 rmb_dma_addr; /* RMB virtual address */
136 u8 reserved2;
137 u8 psn[3]; /* packet sequence number */
138 struct smc_clc_msg_trail smcr_trl;
139 /* eye catcher "SMCR" EBCDIC */
140 } __packed;
141 struct { /* SMC-D */
142 u64 gid; /* Sender GID */
143 u64 token; /* DMB token */
144 u8 dmbe_idx; /* DMBE index */
145 #if defined(__BIG_ENDIAN_BITFIELD)
146 u8 dmbe_size : 4, /* buf size (compressed) */
147 reserved3 : 4;
148 #elif defined(__LITTLE_ENDIAN_BITFIELD)
149 u8 reserved3 : 4,
150 dmbe_size : 4;
151 #endif
152 u16 reserved4;
153 u32 linkid; /* Link identifier */
154 u32 reserved5[3];
155 struct smc_clc_msg_trail smcd_trl;
156 /* eye catcher "SMCD" EBCDIC */
157 } __packed;
158 };
159 } __packed; /* format defined in RFC7609 */
160
161 struct smc_clc_msg_decline { /* clc decline message */
162 struct smc_clc_msg_hdr hdr;
163 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
164 __be32 peer_diagnosis; /* diagnosis information */
165 u8 reserved2[4];
166 struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
167 } __aligned(4);
168
169 /* determine start of the prefix area within the proposal message */
170 static inline struct smc_clc_msg_proposal_prefix *
smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal * pclc)171 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
172 {
173 return (struct smc_clc_msg_proposal_prefix *)
174 ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
175 }
176
177 /* get SMC-D info from proposal message */
178 static inline struct smc_clc_msg_smcd *
smc_get_clc_msg_smcd(struct smc_clc_msg_proposal * prop)179 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
180 {
181 if (ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
182 return NULL;
183
184 return (struct smc_clc_msg_smcd *)(prop + 1);
185 }
186
187 struct smcd_dev;
188 struct smc_init_info;
189
190 int smc_clc_prfx_match(struct socket *clcsock,
191 struct smc_clc_msg_proposal_prefix *prop);
192 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
193 u8 expected_type, unsigned long timeout);
194 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
195 int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
196 struct smc_init_info *ini);
197 int smc_clc_send_confirm(struct smc_sock *smc);
198 int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);
199
200 #endif
201