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_TYPE_R 0 /* SMC-R only */
26 #define SMC_TYPE_D 1 /* SMC-D only */
27 #define SMC_TYPE_N 2 /* neither SMC-R nor SMC-D */
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_MODEUNSUPP 0x03040000 /* smc modes do not match (R or D)*/
41 #define SMC_CLC_DECL_RMBE_EC 0x03050000 /* peer has eyecatcher in RMBE */
42 #define SMC_CLC_DECL_OPTUNSUPP 0x03060000 /* fastopen sockopt not supported */
43 #define SMC_CLC_DECL_DIFFPREFIX 0x03070000 /* IP prefix / subnet mismatch */
44 #define SMC_CLC_DECL_GETVLANERR 0x03080000 /* err to get vlan id of ip device*/
45 #define SMC_CLC_DECL_ISMVLANERR 0x03090000 /* err to reg vlan id on ism dev */
46 #define SMC_CLC_DECL_NOACTLINK 0x030a0000 /* no active smc-r link in lgr */
47 #define SMC_CLC_DECL_NOSRVLINK 0x030b0000 /* SMC-R link from srv not found */
48 #define SMC_CLC_DECL_VERSMISMAT 0x030c0000 /* SMC version mismatch */
49 #define SMC_CLC_DECL_MAX_DMB 0x030d0000 /* SMC-D DMB limit exceeded */
50 #define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */
51 #define SMC_CLC_DECL_PEERDECL 0x05000000 /* peer declined during handshake */
52 #define SMC_CLC_DECL_INTERR 0x09990000 /* internal error */
53 #define SMC_CLC_DECL_ERR_RTOK 0x09990001 /* rtoken handling failed */
54 #define SMC_CLC_DECL_ERR_RDYLNK 0x09990002 /* ib ready link failed */
55 #define SMC_CLC_DECL_ERR_REGRMB 0x09990003 /* reg rmb failed */
57 #define SMC_FIRST_CONTACT_MASK 0b10 /* first contact bit within typev2 */
59 struct smc_clc_msg_hdr { /* header1 of clc messages */
60 u8 eyecatcher[4]; /* eye catcher */
61 u8 type; /* proposal / accept / confirm / decline */
63 #if defined(__BIG_ENDIAN_BITFIELD)
67 #elif defined(__LITTLE_ENDIAN_BITFIELD)
72 } __packed; /* format defined in RFC7609 */
74 struct smc_clc_msg_trail { /* trailer of clc messages */
78 struct smc_clc_msg_local { /* header2 of clc messages */
79 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
80 u8 gid[16]; /* gid of ib_device port */
81 u8 mac[6]; /* mac of ib_device port */
84 /* Struct would be 4 byte aligned, but it is used in an array that is sent
85 * to peers and must conform to RFC7609, hence we need to use packed here.
87 struct smc_clc_ipv6_prefix {
88 struct in6_addr prefix;
90 } __packed; /* format defined in RFC7609 */
92 #if defined(__BIG_ENDIAN_BITFIELD)
93 struct smc_clc_v2_flag {
98 #elif defined(__LITTLE_ENDIAN_BITFIELD)
99 struct smc_clc_v2_flag {
106 struct smc_clnt_opts_area_hdr {
107 u8 eid_cnt; /* number of user defined EIDs */
108 u8 ism_gid_cnt; /* number of ISMv2 GIDs */
110 struct smc_clc_v2_flag flag;
112 __be16 smcd_v2_ext_offset; /* SMC-Dv2 Extension Offset */
115 struct smc_clc_smcd_gid_chid {
116 __be64 gid; /* ISM GID */
117 __be16 chid; /* ISMv2 CHID */
118 } __packed; /* format defined in
119 * IBM Shared Memory Communications Version 2
120 * (https://www.ibm.com/support/pages/node/6326337)
123 struct smc_clc_v2_extension {
124 struct smc_clnt_opts_area_hdr hdr;
125 u8 roce[16]; /* RoCEv2 GID */
127 u8 user_eids[][SMC_MAX_EID_LEN];
130 struct smc_clc_msg_proposal_prefix { /* prefix part of clc proposal message*/
131 __be32 outgoing_subnet; /* subnet mask */
132 u8 prefix_len; /* number of significant bits in mask */
134 u8 ipv6_prefixes_cnt; /* number of IPv6 prefixes in prefix array */
137 struct smc_clc_msg_smcd { /* SMC-D GID information */
138 struct smc_clc_smcd_gid_chid ism; /* ISM native GID+CHID of requestor */
139 __be16 v2_ext_offset; /* SMC Version 2 Extension Offset */
143 struct smc_clc_smcd_v2_extension {
144 u8 system_eid[SMC_MAX_EID_LEN];
146 struct smc_clc_smcd_gid_chid gidchid[];
149 struct smc_clc_msg_proposal { /* clc proposal message sent by Linux */
150 struct smc_clc_msg_hdr hdr;
151 struct smc_clc_msg_local lcl;
152 __be16 iparea_offset; /* offset to IP address information area */
155 #define SMC_CLC_MAX_V6_PREFIX 8
157 struct smc_clc_msg_proposal_area {
158 struct smc_clc_msg_proposal pclc_base;
159 struct smc_clc_msg_smcd pclc_smcd;
160 struct smc_clc_msg_proposal_prefix pclc_prfx;
161 struct smc_clc_ipv6_prefix pclc_prfx_ipv6[SMC_CLC_MAX_V6_PREFIX];
162 struct smc_clc_v2_extension pclc_v2_ext;
163 struct smc_clc_smcd_v2_extension pclc_smcd_v2_ext;
164 struct smc_clc_smcd_gid_chid pclc_gidchids[SMC_MAX_ISM_DEVS];
165 struct smc_clc_msg_trail pclc_trl;
168 struct smcr_clc_msg_accept_confirm { /* SMCR accept/confirm */
169 struct smc_clc_msg_local lcl;
170 u8 qpn[3]; /* QP number */
171 __be32 rmb_rkey; /* RMB rkey */
172 u8 rmbe_idx; /* Index of RMBE in RMB */
173 __be32 rmbe_alert_token; /* unique connection id */
174 #if defined(__BIG_ENDIAN_BITFIELD)
175 u8 rmbe_size : 4, /* buf size (compressed) */
176 qp_mtu : 4; /* QP mtu */
177 #elif defined(__LITTLE_ENDIAN_BITFIELD)
182 __be64 rmb_dma_addr; /* RMB virtual address */
184 u8 psn[3]; /* packet sequence number */
187 struct smcd_clc_msg_accept_confirm_common { /* SMCD accept/confirm */
188 u64 gid; /* Sender GID */
189 u64 token; /* DMB token */
190 u8 dmbe_idx; /* DMBE index */
191 #if defined(__BIG_ENDIAN_BITFIELD)
192 u8 dmbe_size : 4, /* buf size (compressed) */
194 #elif defined(__LITTLE_ENDIAN_BITFIELD)
199 __be32 linkid; /* Link identifier */
202 #define SMC_CLC_OS_ZOS 1
203 #define SMC_CLC_OS_LINUX 2
204 #define SMC_CLC_OS_AIX 3
206 struct smc_clc_first_contact_ext {
208 #if defined(__BIG_ENDIAN_BITFIELD)
211 #elif defined(__LITTLE_ENDIAN_BITFIELD)
216 u8 hostname[SMC_MAX_HOSTNAME_LEN];
219 struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
220 struct smc_clc_msg_hdr hdr;
222 struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
224 struct smcd_clc_msg_accept_confirm_common d0;
228 } __packed; /* format defined in RFC7609 */
230 struct smc_clc_msg_accept_confirm_v2 { /* clc accept / confirm message */
231 struct smc_clc_msg_hdr hdr;
233 struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
235 struct smcd_clc_msg_accept_confirm_common d0;
237 u8 eid[SMC_MAX_EID_LEN];
243 struct smc_clc_msg_decline { /* clc decline message */
244 struct smc_clc_msg_hdr hdr;
245 u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
246 __be32 peer_diagnosis; /* diagnosis information */
247 #if defined(__BIG_ENDIAN_BITFIELD)
250 #elif defined(__LITTLE_ENDIAN_BITFIELD)
255 struct smc_clc_msg_trail trl; /* eye catcher "SMCD" or "SMCR" EBCDIC */
258 /* determine start of the prefix area within the proposal message */
259 static inline struct smc_clc_msg_proposal_prefix *
260 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
262 return (struct smc_clc_msg_proposal_prefix *)
263 ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
266 static inline bool smcr_indicated(int smc_type)
268 return smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B;
271 static inline bool smcd_indicated(int smc_type)
273 return smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B;
276 /* get SMC-D info from proposal message */
277 static inline struct smc_clc_msg_smcd *
278 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
280 if (smcd_indicated(prop->hdr.typev1) &&
281 ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
284 return (struct smc_clc_msg_smcd *)(prop + 1);
287 static inline struct smc_clc_v2_extension *
288 smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop)
290 struct smc_clc_msg_smcd *prop_smcd = smc_get_clc_msg_smcd(prop);
292 if (!prop_smcd || !ntohs(prop_smcd->v2_ext_offset))
295 return (struct smc_clc_v2_extension *)
297 offsetof(struct smc_clc_msg_smcd, v2_ext_offset) +
298 sizeof(prop_smcd->v2_ext_offset) +
299 ntohs(prop_smcd->v2_ext_offset));
302 static inline struct smc_clc_smcd_v2_extension *
303 smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
307 if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset))
310 return (struct smc_clc_smcd_v2_extension *)
312 offsetof(struct smc_clc_v2_extension, hdr) +
313 offsetof(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset) +
314 sizeof(prop_v2ext->hdr.smcd_v2_ext_offset) +
315 ntohs(prop_v2ext->hdr.smcd_v2_ext_offset));
319 struct smc_init_info;
321 int smc_clc_prfx_match(struct socket *clcsock,
322 struct smc_clc_msg_proposal_prefix *prop);
323 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
324 u8 expected_type, unsigned long timeout);
325 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version);
326 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini);
327 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
329 int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
331 void smc_clc_init(void) __init;