xref: /kernel/linux/linux-5.10/net/smc/smc_clc.h (revision 8c2ecf20)
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_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		      */
56
57#define SMC_FIRST_CONTACT_MASK	0b10	/* first contact bit within typev2 */
58
59struct smc_clc_msg_hdr {	/* header1 of clc messages */
60	u8 eyecatcher[4];	/* eye catcher */
61	u8 type;		/* proposal / accept / confirm / decline */
62	__be16 length;
63#if defined(__BIG_ENDIAN_BITFIELD)
64	u8 version : 4,
65	   typev2  : 2,
66	   typev1  : 2;
67#elif defined(__LITTLE_ENDIAN_BITFIELD)
68	u8 typev1  : 2,
69	   typev2  : 2,
70	   version : 4;
71#endif
72} __packed;			/* format defined in RFC7609 */
73
74struct smc_clc_msg_trail {	/* trailer of clc messages */
75	u8 eyecatcher[4];
76};
77
78struct 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 */
82};
83
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.
86 */
87struct smc_clc_ipv6_prefix {
88	struct in6_addr prefix;
89	u8 prefix_len;
90} __packed;			/* format defined in RFC7609 */
91
92#if defined(__BIG_ENDIAN_BITFIELD)
93struct smc_clc_v2_flag {
94	u8 release : 4,
95	   rsvd    : 3,
96	   seid    : 1;
97};
98#elif defined(__LITTLE_ENDIAN_BITFIELD)
99struct smc_clc_v2_flag {
100	u8 seid   : 1,
101	rsvd      : 3,
102	release   : 4;
103};
104#endif
105
106struct smc_clnt_opts_area_hdr {
107	u8 eid_cnt;		/* number of user defined EIDs */
108	u8 ism_gid_cnt;		/* number of ISMv2 GIDs */
109	u8 reserved1;
110	struct smc_clc_v2_flag flag;
111	u8 reserved2[2];
112	__be16 smcd_v2_ext_offset; /* SMC-Dv2 Extension Offset */
113};
114
115struct 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)
121			 */
122
123struct smc_clc_v2_extension {
124	struct smc_clnt_opts_area_hdr hdr;
125	u8 roce[16];		/* RoCEv2 GID */
126	u8 reserved[16];
127	u8 user_eids[][SMC_MAX_EID_LEN];
128};
129
130struct 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 */
133	u8 reserved[2];
134	u8 ipv6_prefixes_cnt;	/* number of IPv6 prefixes in prefix array */
135} __aligned(4);
136
137struct 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 */
140	u8 reserved[28];
141};
142
143struct smc_clc_smcd_v2_extension {
144	u8 system_eid[SMC_MAX_EID_LEN];
145	u8 reserved[16];
146	struct smc_clc_smcd_gid_chid gidchid[];
147};
148
149struct 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 */
153} __aligned(4);
154
155#define SMC_CLC_MAX_V6_PREFIX		8
156
157struct 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;
166};
167
168struct 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)
178	u8 qp_mtu   : 4,
179	   rmbe_size : 4;
180#endif
181	u8 reserved;
182	__be64 rmb_dma_addr;	/* RMB virtual address */
183	u8 reserved2;
184	u8 psn[3];		/* packet sequence number */
185} __packed;
186
187struct 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) */
193	   reserved3 : 4;
194#elif defined(__LITTLE_ENDIAN_BITFIELD)
195	u8 reserved3 : 4,
196	   dmbe_size : 4;
197#endif
198	u16 reserved4;
199	__be32 linkid;		/* Link identifier */
200} __packed;
201
202#define SMC_CLC_OS_ZOS		1
203#define SMC_CLC_OS_LINUX	2
204#define SMC_CLC_OS_AIX		3
205
206struct smc_clc_first_contact_ext {
207	u8 reserved1;
208#if defined(__BIG_ENDIAN_BITFIELD)
209	u8 os_type : 4,
210	   release : 4;
211#elif defined(__LITTLE_ENDIAN_BITFIELD)
212	u8 release : 4,
213	   os_type : 4;
214#endif
215	u8 reserved2[2];
216	u8 hostname[SMC_MAX_HOSTNAME_LEN];
217};
218
219struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
220	struct smc_clc_msg_hdr hdr;
221	union {
222		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
223		struct { /* SMC-D */
224			struct smcd_clc_msg_accept_confirm_common d0;
225			u32 reserved5[3];
226		};
227	};
228} __packed;			/* format defined in RFC7609 */
229
230struct smc_clc_msg_accept_confirm_v2 {	/* clc accept / confirm message */
231	struct smc_clc_msg_hdr hdr;
232	union {
233		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
234		struct { /* SMC-D */
235			struct smcd_clc_msg_accept_confirm_common d0;
236			__be16 chid;
237			u8 eid[SMC_MAX_EID_LEN];
238			u8 reserved5[8];
239		};
240	};
241};
242
243struct 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)
248	u8 os_type  : 4,
249	   reserved : 4;
250#elif defined(__LITTLE_ENDIAN_BITFIELD)
251	u8 reserved : 4,
252	   os_type  : 4;
253#endif
254	u8 reserved2[3];
255	struct smc_clc_msg_trail trl; /* eye catcher "SMCD" or "SMCR" EBCDIC */
256} __aligned(4);
257
258/* determine start of the prefix area within the proposal message */
259static inline struct smc_clc_msg_proposal_prefix *
260smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
261{
262	return (struct smc_clc_msg_proposal_prefix *)
263	       ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
264}
265
266static inline bool smcr_indicated(int smc_type)
267{
268	return smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B;
269}
270
271static inline bool smcd_indicated(int smc_type)
272{
273	return smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B;
274}
275
276/* get SMC-D info from proposal message */
277static inline struct smc_clc_msg_smcd *
278smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
279{
280	if (smcd_indicated(prop->hdr.typev1) &&
281	    ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
282		return NULL;
283
284	return (struct smc_clc_msg_smcd *)(prop + 1);
285}
286
287static inline struct smc_clc_v2_extension *
288smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop)
289{
290	struct smc_clc_msg_smcd *prop_smcd = smc_get_clc_msg_smcd(prop);
291
292	if (!prop_smcd || !ntohs(prop_smcd->v2_ext_offset))
293		return NULL;
294
295	return (struct smc_clc_v2_extension *)
296	       ((u8 *)prop_smcd +
297	       offsetof(struct smc_clc_msg_smcd, v2_ext_offset) +
298	       sizeof(prop_smcd->v2_ext_offset) +
299	       ntohs(prop_smcd->v2_ext_offset));
300}
301
302static inline struct smc_clc_smcd_v2_extension *
303smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
304{
305	if (!prop_v2ext)
306		return NULL;
307	if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset))
308		return NULL;
309
310	return (struct smc_clc_smcd_v2_extension *)
311		((u8 *)prop_v2ext +
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));
316}
317
318struct smcd_dev;
319struct smc_init_info;
320
321int smc_clc_prfx_match(struct socket *clcsock,
322		       struct smc_clc_msg_proposal_prefix *prop);
323int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
324		     u8 expected_type, unsigned long timeout);
325int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version);
326int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini);
327int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
328			 u8 version);
329int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
330			u8 version);
331void smc_clc_init(void) __init;
332
333#endif
334