1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
5 * CLC (connection layer control) handshake over initial TCP socket to
6 * prepare for RDMA traffic
8 * Copyright IBM Corp. 2016
10 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
16 #include <rdma/ib_verbs.h>
20 #define SMC_CLC_PROPOSAL 0x01
21 #define SMC_CLC_ACCEPT 0x02
22 #define SMC_CLC_CONFIRM 0x03
23 #define SMC_CLC_DECLINE 0x04
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 */
38 #define SMC_CLC_DECL_MODEUNSUPP 0x03040000 /* smc modes do not match (R or D)*/
39 #define SMC_CLC_DECL_RMBE_EC 0x03050000 /* peer has eyecatcher in RMBE */
40 #define SMC_CLC_DECL_OPTUNSUPP 0x03060000 /* fastopen sockopt not supported */
41 #define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */
42 #define SMC_CLC_DECL_PEERDECL 0x05000000 /* peer declined during handshake */
43 #define SMC_CLC_DECL_INTERR 0x99990000 /* internal error */
44 #define SMC_CLC_DECL_ERR_RTOK 0x99990001 /* rtoken handling failed */
45 #define SMC_CLC_DECL_ERR_RDYLNK 0x99990002 /* ib ready link failed */
46 #define SMC_CLC_DECL_ERR_REGRMB 0x99990003 /* reg rmb failed */
48 struct smc_clc_msg_hdr { /* header1 of clc messages */
49 u8 eyecatcher[4]; /* eye catcher */
50 u8 type; /* proposal / accept / confirm / decline */
52 #if defined(__BIG_ENDIAN_BITFIELD)
57 #elif defined(__LITTLE_ENDIAN_BITFIELD)
63 } __packed; /* format defined in RFC7609 */
65 struct smc_clc_msg_trail { /* trailer of clc messages */
69 struct smc_clc_msg_local { /* header2 of clc messages */
70 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
71 u8 gid[16]; /* gid of ib_device port */
72 u8 mac[6]; /* mac of ib_device port */
75 #define SMC_CLC_MAX_V6_PREFIX 8
77 /* Struct would be 4 byte aligned, but it is used in an array that is sent
78 * to peers and must conform to RFC7609, hence we need to use packed here.
80 struct smc_clc_ipv6_prefix {
81 struct in6_addr prefix;
83 } __packed; /* format defined in RFC7609 */
85 struct smc_clc_msg_proposal_prefix { /* prefix part of clc proposal message*/
86 __be32 outgoing_subnet; /* subnet mask */
87 u8 prefix_len; /* number of significant bits in mask */
89 u8 ipv6_prefixes_cnt; /* number of IPv6 prefixes in prefix array */
92 struct smc_clc_msg_smcd { /* SMC-D GID information */
93 u64 gid; /* ISM GID of requestor */
97 struct smc_clc_msg_proposal { /* clc proposal message sent by Linux */
98 struct smc_clc_msg_hdr hdr;
99 struct smc_clc_msg_local lcl;
100 __be16 iparea_offset; /* offset to IP address information area */
103 #define SMC_CLC_PROPOSAL_MAX_OFFSET 0x28
104 #define SMC_CLC_PROPOSAL_MAX_PREFIX (SMC_CLC_MAX_V6_PREFIX * \
105 sizeof(struct smc_clc_ipv6_prefix))
106 #define SMC_CLC_MAX_LEN (sizeof(struct smc_clc_msg_proposal) + \
107 SMC_CLC_PROPOSAL_MAX_OFFSET + \
108 sizeof(struct smc_clc_msg_proposal_prefix) + \
109 SMC_CLC_PROPOSAL_MAX_PREFIX + \
110 sizeof(struct smc_clc_msg_trail))
112 struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
113 struct smc_clc_msg_hdr hdr;
116 struct smc_clc_msg_local lcl;
117 u8 qpn[3]; /* QP number */
118 __be32 rmb_rkey; /* RMB rkey */
119 u8 rmbe_idx; /* Index of RMBE in RMB */
120 __be32 rmbe_alert_token;/* unique connection id */
121 #if defined(__BIG_ENDIAN_BITFIELD)
122 u8 rmbe_size : 4, /* buf size (compressed) */
123 qp_mtu : 4; /* QP mtu */
124 #elif defined(__LITTLE_ENDIAN_BITFIELD)
129 __be64 rmb_dma_addr; /* RMB virtual address */
131 u8 psn[3]; /* packet sequence number */
132 struct smc_clc_msg_trail smcr_trl;
133 /* eye catcher "SMCR" EBCDIC */
136 u64 gid; /* Sender GID */
137 u64 token; /* DMB token */
138 u8 dmbe_idx; /* DMBE index */
139 #if defined(__BIG_ENDIAN_BITFIELD)
140 u8 dmbe_size : 4, /* buf size (compressed) */
142 #elif defined(__LITTLE_ENDIAN_BITFIELD)
147 u32 linkid; /* Link identifier */
149 struct smc_clc_msg_trail smcd_trl;
150 /* eye catcher "SMCD" EBCDIC */
153 } __packed; /* format defined in RFC7609 */
155 struct smc_clc_msg_decline { /* clc decline message */
156 struct smc_clc_msg_hdr hdr;
157 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
158 __be32 peer_diagnosis; /* diagnosis information */
160 struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
163 /* determine start of the prefix area within the proposal message */
164 static inline struct smc_clc_msg_proposal_prefix *
165 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
167 return (struct smc_clc_msg_proposal_prefix *)
168 ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
171 /* get SMC-D info from proposal message */
172 static inline struct smc_clc_msg_smcd *
173 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
175 if (ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
178 return (struct smc_clc_msg_smcd *)(prop + 1);
183 int smc_clc_prfx_match(struct socket *clcsock,
184 struct smc_clc_msg_proposal_prefix *prop);
185 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
186 u8 expected_type, unsigned long timeout);
187 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
188 int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
189 struct smc_ib_device *smcibdev, u8 ibport, u8 gid[],
190 struct smcd_dev *ismdev);
191 int smc_clc_send_confirm(struct smc_sock *smc);
192 int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);