xref: /linux/net/smc/smc_clc.h (revision 0c8a32eed1625a65798286fb73fea8710a908545)
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_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_NOISM2SUPP	0x03030003  /* hardware has no ISMv2 support  */
41 #define SMC_CLC_DECL_NOV2EXT	0x03030004  /* peer sent no clc v2 extension  */
42 #define SMC_CLC_DECL_NOV2DEXT	0x03030005  /* peer sent no clc SMC-Dv2 ext.  */
43 #define SMC_CLC_DECL_NOSEID	0x03030006  /* peer sent no SEID	      */
44 #define SMC_CLC_DECL_NOSMCD2DEV	0x03030007  /* no SMC-Dv2 device found	      */
45 #define SMC_CLC_DECL_MODEUNSUPP	0x03040000  /* smc modes do not match (R or D)*/
46 #define SMC_CLC_DECL_RMBE_EC	0x03050000  /* peer has eyecatcher in RMBE    */
47 #define SMC_CLC_DECL_OPTUNSUPP	0x03060000  /* fastopen sockopt not supported */
48 #define SMC_CLC_DECL_DIFFPREFIX	0x03070000  /* IP prefix / subnet mismatch    */
49 #define SMC_CLC_DECL_GETVLANERR	0x03080000  /* err to get vlan id of ip device*/
50 #define SMC_CLC_DECL_ISMVLANERR	0x03090000  /* err to reg vlan id on ism dev  */
51 #define SMC_CLC_DECL_NOACTLINK	0x030a0000  /* no active smc-r link in lgr    */
52 #define SMC_CLC_DECL_NOSRVLINK	0x030b0000  /* SMC-R link from srv not found  */
53 #define SMC_CLC_DECL_VERSMISMAT	0x030c0000  /* SMC version mismatch	      */
54 #define SMC_CLC_DECL_MAX_DMB	0x030d0000  /* SMC-D DMB limit exceeded       */
55 #define SMC_CLC_DECL_SYNCERR	0x04000000  /* synchronization error          */
56 #define SMC_CLC_DECL_PEERDECL	0x05000000  /* peer declined during handshake */
57 #define SMC_CLC_DECL_INTERR	0x09990000  /* internal error		      */
58 #define SMC_CLC_DECL_ERR_RTOK	0x09990001  /*	 rtoken handling failed       */
59 #define SMC_CLC_DECL_ERR_RDYLNK	0x09990002  /*	 ib ready link failed	      */
60 #define SMC_CLC_DECL_ERR_REGRMB	0x09990003  /*	 reg rmb failed		      */
61 
62 #define SMC_FIRST_CONTACT_MASK	0b10	/* first contact bit within typev2 */
63 
64 struct smc_clc_msg_hdr {	/* header1 of clc messages */
65 	u8 eyecatcher[4];	/* eye catcher */
66 	u8 type;		/* proposal / accept / confirm / decline */
67 	__be16 length;
68 #if defined(__BIG_ENDIAN_BITFIELD)
69 	u8 version : 4,
70 	   typev2  : 2,
71 	   typev1  : 2;
72 #elif defined(__LITTLE_ENDIAN_BITFIELD)
73 	u8 typev1  : 2,
74 	   typev2  : 2,
75 	   version : 4;
76 #endif
77 } __packed;			/* format defined in RFC7609 */
78 
79 struct smc_clc_msg_trail {	/* trailer of clc messages */
80 	u8 eyecatcher[4];
81 };
82 
83 struct smc_clc_msg_local {	/* header2 of clc messages */
84 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
85 	u8 gid[16];		/* gid of ib_device port */
86 	u8 mac[6];		/* mac of ib_device port */
87 };
88 
89 /* Struct would be 4 byte aligned, but it is used in an array that is sent
90  * to peers and must conform to RFC7609, hence we need to use packed here.
91  */
92 struct smc_clc_ipv6_prefix {
93 	struct in6_addr prefix;
94 	u8 prefix_len;
95 } __packed;			/* format defined in RFC7609 */
96 
97 #if defined(__BIG_ENDIAN_BITFIELD)
98 struct smc_clc_v2_flag {
99 	u8 release : 4,
100 	   rsvd    : 3,
101 	   seid    : 1;
102 };
103 #elif defined(__LITTLE_ENDIAN_BITFIELD)
104 struct smc_clc_v2_flag {
105 	u8 seid   : 1,
106 	rsvd      : 3,
107 	release   : 4;
108 };
109 #endif
110 
111 struct smc_clnt_opts_area_hdr {
112 	u8 eid_cnt;		/* number of user defined EIDs */
113 	u8 ism_gid_cnt;		/* number of ISMv2 GIDs */
114 	u8 reserved1;
115 	struct smc_clc_v2_flag flag;
116 	u8 reserved2[2];
117 	__be16 smcd_v2_ext_offset; /* SMC-Dv2 Extension Offset */
118 };
119 
120 struct smc_clc_smcd_gid_chid {
121 	__be64 gid;		/* ISM GID */
122 	__be16 chid;		/* ISMv2 CHID */
123 } __packed;		/* format defined in
124 			 * IBM Shared Memory Communications Version 2
125 			 * (https://www.ibm.com/support/pages/node/6326337)
126 			 */
127 
128 struct smc_clc_v2_extension {
129 	struct smc_clnt_opts_area_hdr hdr;
130 	u8 roce[16];		/* RoCEv2 GID */
131 	u8 reserved[16];
132 	u8 user_eids[][SMC_MAX_EID_LEN];
133 };
134 
135 struct smc_clc_msg_proposal_prefix {	/* prefix part of clc proposal message*/
136 	__be32 outgoing_subnet;	/* subnet mask */
137 	u8 prefix_len;		/* number of significant bits in mask */
138 	u8 reserved[2];
139 	u8 ipv6_prefixes_cnt;	/* number of IPv6 prefixes in prefix array */
140 } __aligned(4);
141 
142 struct smc_clc_msg_smcd {	/* SMC-D GID information */
143 	struct smc_clc_smcd_gid_chid ism; /* ISM native GID+CHID of requestor */
144 	__be16 v2_ext_offset;	/* SMC Version 2 Extension Offset */
145 	u8 reserved[28];
146 };
147 
148 struct smc_clc_smcd_v2_extension {
149 	u8 system_eid[SMC_MAX_EID_LEN];
150 	u8 reserved[16];
151 	struct smc_clc_smcd_gid_chid gidchid[];
152 };
153 
154 struct smc_clc_msg_proposal {	/* clc proposal message sent by Linux */
155 	struct smc_clc_msg_hdr hdr;
156 	struct smc_clc_msg_local lcl;
157 	__be16 iparea_offset;	/* offset to IP address information area */
158 } __aligned(4);
159 
160 #define SMC_CLC_MAX_V6_PREFIX		8
161 
162 struct smc_clc_msg_proposal_area {
163 	struct smc_clc_msg_proposal		pclc_base;
164 	struct smc_clc_msg_smcd			pclc_smcd;
165 	struct smc_clc_msg_proposal_prefix	pclc_prfx;
166 	struct smc_clc_ipv6_prefix	pclc_prfx_ipv6[SMC_CLC_MAX_V6_PREFIX];
167 	struct smc_clc_v2_extension		pclc_v2_ext;
168 	struct smc_clc_smcd_v2_extension	pclc_smcd_v2_ext;
169 	struct smc_clc_smcd_gid_chid		pclc_gidchids[SMC_MAX_ISM_DEVS];
170 	struct smc_clc_msg_trail		pclc_trl;
171 };
172 
173 struct smcr_clc_msg_accept_confirm {	/* SMCR accept/confirm */
174 	struct smc_clc_msg_local lcl;
175 	u8 qpn[3];			/* QP number */
176 	__be32 rmb_rkey;		/* RMB rkey */
177 	u8 rmbe_idx;			/* Index of RMBE in RMB */
178 	__be32 rmbe_alert_token;	/* unique connection id */
179  #if defined(__BIG_ENDIAN_BITFIELD)
180 	u8 rmbe_size : 4,		/* buf size (compressed) */
181 	   qp_mtu   : 4;		/* QP mtu */
182 #elif defined(__LITTLE_ENDIAN_BITFIELD)
183 	u8 qp_mtu   : 4,
184 	   rmbe_size : 4;
185 #endif
186 	u8 reserved;
187 	__be64 rmb_dma_addr;	/* RMB virtual address */
188 	u8 reserved2;
189 	u8 psn[3];		/* packet sequence number */
190 } __packed;
191 
192 struct smcd_clc_msg_accept_confirm_common {	/* SMCD accept/confirm */
193 	u64 gid;		/* Sender GID */
194 	u64 token;		/* DMB token */
195 	u8 dmbe_idx;		/* DMBE index */
196 #if defined(__BIG_ENDIAN_BITFIELD)
197 	u8 dmbe_size : 4,	/* buf size (compressed) */
198 	   reserved3 : 4;
199 #elif defined(__LITTLE_ENDIAN_BITFIELD)
200 	u8 reserved3 : 4,
201 	   dmbe_size : 4;
202 #endif
203 	u16 reserved4;
204 	__be32 linkid;		/* Link identifier */
205 } __packed;
206 
207 #define SMC_CLC_OS_ZOS		1
208 #define SMC_CLC_OS_LINUX	2
209 #define SMC_CLC_OS_AIX		3
210 
211 struct smc_clc_first_contact_ext {
212 	u8 reserved1;
213 #if defined(__BIG_ENDIAN_BITFIELD)
214 	u8 os_type : 4,
215 	   release : 4;
216 #elif defined(__LITTLE_ENDIAN_BITFIELD)
217 	u8 release : 4,
218 	   os_type : 4;
219 #endif
220 	u8 reserved2[2];
221 	u8 hostname[SMC_MAX_HOSTNAME_LEN];
222 };
223 
224 struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
225 	struct smc_clc_msg_hdr hdr;
226 	union {
227 		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
228 		struct { /* SMC-D */
229 			struct smcd_clc_msg_accept_confirm_common d0;
230 			u32 reserved5[3];
231 		};
232 	};
233 } __packed;			/* format defined in RFC7609 */
234 
235 struct smc_clc_msg_accept_confirm_v2 {	/* clc accept / confirm message */
236 	struct smc_clc_msg_hdr hdr;
237 	union {
238 		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
239 		struct { /* SMC-D */
240 			struct smcd_clc_msg_accept_confirm_common d0;
241 			__be16 chid;
242 			u8 eid[SMC_MAX_EID_LEN];
243 			u8 reserved5[8];
244 		};
245 	};
246 };
247 
248 struct smc_clc_msg_decline {	/* clc decline message */
249 	struct smc_clc_msg_hdr hdr;
250 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
251 	__be32 peer_diagnosis;	/* diagnosis information */
252 #if defined(__BIG_ENDIAN_BITFIELD)
253 	u8 os_type  : 4,
254 	   reserved : 4;
255 #elif defined(__LITTLE_ENDIAN_BITFIELD)
256 	u8 reserved : 4,
257 	   os_type  : 4;
258 #endif
259 	u8 reserved2[3];
260 	struct smc_clc_msg_trail trl; /* eye catcher "SMCD" or "SMCR" EBCDIC */
261 } __aligned(4);
262 
263 /* determine start of the prefix area within the proposal message */
264 static inline struct smc_clc_msg_proposal_prefix *
265 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
266 {
267 	return (struct smc_clc_msg_proposal_prefix *)
268 	       ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
269 }
270 
271 static inline bool smcr_indicated(int smc_type)
272 {
273 	return smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B;
274 }
275 
276 static inline bool smcd_indicated(int smc_type)
277 {
278 	return smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B;
279 }
280 
281 /* get SMC-D info from proposal message */
282 static inline struct smc_clc_msg_smcd *
283 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
284 {
285 	if (smcd_indicated(prop->hdr.typev1) &&
286 	    ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
287 		return NULL;
288 
289 	return (struct smc_clc_msg_smcd *)(prop + 1);
290 }
291 
292 static inline struct smc_clc_v2_extension *
293 smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop)
294 {
295 	struct smc_clc_msg_smcd *prop_smcd = smc_get_clc_msg_smcd(prop);
296 
297 	if (!prop_smcd || !ntohs(prop_smcd->v2_ext_offset))
298 		return NULL;
299 
300 	return (struct smc_clc_v2_extension *)
301 	       ((u8 *)prop_smcd +
302 	       offsetof(struct smc_clc_msg_smcd, v2_ext_offset) +
303 	       sizeof(prop_smcd->v2_ext_offset) +
304 	       ntohs(prop_smcd->v2_ext_offset));
305 }
306 
307 static inline struct smc_clc_smcd_v2_extension *
308 smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
309 {
310 	if (!prop_v2ext)
311 		return NULL;
312 	if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset))
313 		return NULL;
314 
315 	return (struct smc_clc_smcd_v2_extension *)
316 		((u8 *)prop_v2ext +
317 		 offsetof(struct smc_clc_v2_extension, hdr) +
318 		 offsetof(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset) +
319 		 sizeof(prop_v2ext->hdr.smcd_v2_ext_offset) +
320 		 ntohs(prop_v2ext->hdr.smcd_v2_ext_offset));
321 }
322 
323 struct smcd_dev;
324 struct smc_init_info;
325 
326 int smc_clc_prfx_match(struct socket *clcsock,
327 		       struct smc_clc_msg_proposal_prefix *prop);
328 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
329 		     u8 expected_type, unsigned long timeout);
330 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version);
331 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini);
332 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
333 			 u8 version);
334 int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
335 			u8 version);
336 void smc_clc_init(void) __init;
337 void smc_clc_get_hostname(u8 **host);
338 
339 #endif
340