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 (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_SYNCERR 0x04000000 /* synchronization error */
47 #define SMC_CLC_DECL_PEERDECL 0x05000000 /* peer declined during handshake */
48 #define SMC_CLC_DECL_INTERR 0x09990000 /* internal error */
49 #define SMC_CLC_DECL_ERR_RTOK 0x09990001 /* rtoken handling failed */
50 #define SMC_CLC_DECL_ERR_RDYLNK 0x09990002 /* ib ready link failed */
51 #define SMC_CLC_DECL_ERR_REGRMB 0x09990003 /* reg rmb failed */
53 struct smc_clc_msg_hdr { /* header1 of clc messages */
54 u8 eyecatcher[4]; /* eye catcher */
55 u8 type; /* proposal / accept / confirm / decline */
57 #if defined(__BIG_ENDIAN_BITFIELD)
62 #elif defined(__LITTLE_ENDIAN_BITFIELD)
68 } __packed; /* format defined in RFC7609 */
70 struct smc_clc_msg_trail { /* trailer of clc messages */
74 struct smc_clc_msg_local { /* header2 of clc messages */
75 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
76 u8 gid[16]; /* gid of ib_device port */
77 u8 mac[6]; /* mac of ib_device port */
80 #define SMC_CLC_MAX_V6_PREFIX 8
82 /* Struct would be 4 byte aligned, but it is used in an array that is sent
83 * to peers and must conform to RFC7609, hence we need to use packed here.
85 struct smc_clc_ipv6_prefix {
86 struct in6_addr prefix;
88 } __packed; /* format defined in RFC7609 */
90 struct smc_clc_msg_proposal_prefix { /* prefix part of clc proposal message*/
91 __be32 outgoing_subnet; /* subnet mask */
92 u8 prefix_len; /* number of significant bits in mask */
94 u8 ipv6_prefixes_cnt; /* number of IPv6 prefixes in prefix array */
97 struct smc_clc_msg_smcd { /* SMC-D GID information */
98 u64 gid; /* ISM GID of requestor */
102 struct smc_clc_msg_proposal { /* clc proposal message sent by Linux */
103 struct smc_clc_msg_hdr hdr;
104 struct smc_clc_msg_local lcl;
105 __be16 iparea_offset; /* offset to IP address information area */
108 #define SMC_CLC_PROPOSAL_MAX_OFFSET 0x28
109 #define SMC_CLC_PROPOSAL_MAX_PREFIX (SMC_CLC_MAX_V6_PREFIX * \
110 sizeof(struct smc_clc_ipv6_prefix))
111 #define SMC_CLC_MAX_LEN (sizeof(struct smc_clc_msg_proposal) + \
112 SMC_CLC_PROPOSAL_MAX_OFFSET + \
113 sizeof(struct smc_clc_msg_proposal_prefix) + \
114 SMC_CLC_PROPOSAL_MAX_PREFIX + \
115 sizeof(struct smc_clc_msg_trail))
117 struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
118 struct smc_clc_msg_hdr hdr;
121 struct smc_clc_msg_local lcl;
122 u8 qpn[3]; /* QP number */
123 __be32 rmb_rkey; /* RMB rkey */
124 u8 rmbe_idx; /* Index of RMBE in RMB */
125 __be32 rmbe_alert_token;/* unique connection id */
126 #if defined(__BIG_ENDIAN_BITFIELD)
127 u8 rmbe_size : 4, /* buf size (compressed) */
128 qp_mtu : 4; /* QP mtu */
129 #elif defined(__LITTLE_ENDIAN_BITFIELD)
134 __be64 rmb_dma_addr; /* RMB virtual address */
136 u8 psn[3]; /* packet sequence number */
137 struct smc_clc_msg_trail smcr_trl;
138 /* eye catcher "SMCR" EBCDIC */
141 u64 gid; /* Sender GID */
142 u64 token; /* DMB token */
143 u8 dmbe_idx; /* DMBE index */
144 #if defined(__BIG_ENDIAN_BITFIELD)
145 u8 dmbe_size : 4, /* buf size (compressed) */
147 #elif defined(__LITTLE_ENDIAN_BITFIELD)
152 u32 linkid; /* Link identifier */
154 struct smc_clc_msg_trail smcd_trl;
155 /* eye catcher "SMCD" EBCDIC */
158 } __packed; /* format defined in RFC7609 */
160 struct smc_clc_msg_decline { /* clc decline message */
161 struct smc_clc_msg_hdr hdr;
162 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
163 __be32 peer_diagnosis; /* diagnosis information */
165 struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
168 /* determine start of the prefix area within the proposal message */
169 static inline struct smc_clc_msg_proposal_prefix *
170 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
172 return (struct smc_clc_msg_proposal_prefix *)
173 ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
176 /* get SMC-D info from proposal message */
177 static inline struct smc_clc_msg_smcd *
178 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
180 if (ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
183 return (struct smc_clc_msg_smcd *)(prop + 1);
187 struct smc_init_info;
189 int smc_clc_prfx_match(struct socket *clcsock,
190 struct smc_clc_msg_proposal_prefix *prop);
191 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
192 u8 expected_type, unsigned long timeout);
193 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
194 int smc_clc_send_proposal(struct smc_sock *smc, int smc_type,
195 struct smc_init_info *ini);
196 int smc_clc_send_confirm(struct smc_sock *smc);
197 int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);