net/smc/smc_clc.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
  *
  *  CLC (connection layer control) handshake over initial TCP socket to
  *  prepare for RDMA traffic
  *
  *  Copyright IBM Corp. 2016
  *
  *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
  */

 #ifndef _SMC_CLC_H
 #define _SMC_CLC_H

 #include <rdma/ib_verbs.h>

 #include "smc.h"

 #define SMC_CLC_PROPOSAL	0x01
 #define SMC_CLC_ACCEPT		0x02
 #define SMC_CLC_CONFIRM		0x03
 #define SMC_CLC_DECLINE		0x04

 #define SMC_TYPE_R		0		/* SMC-R only		      */
 #define SMC_TYPE_D		1		/* SMC-D only		      */
 #define SMC_TYPE_N		2		/* neither SMC-R nor SMC-D    */
 #define SMC_TYPE_B		3		/* SMC-R and SMC-D	      */
 #define CLC_WAIT_TIME		(6 * HZ)	/* max. wait time on clcsock  */
 #define CLC_WAIT_TIME_SHORT	HZ		/* short wait time on clcsock */
 #define SMC_CLC_DECL_MEM	0x01010000  /* insufficient memory resources  */
 #define SMC_CLC_DECL_TIMEOUT_CL	0x02010000  /* timeout w4 QP confirm link     */
 #define SMC_CLC_DECL_TIMEOUT_AL	0x02020000  /* timeout w4 QP add link	      */
 #define SMC_CLC_DECL_CNFERR	0x03000000  /* configuration error            */
 #define SMC_CLC_DECL_PEERNOSMC	0x03010000  /* peer did not indicate SMC      */
 #define SMC_CLC_DECL_IPSEC	0x03020000  /* IPsec usage		      */
 #define SMC_CLC_DECL_NOSMCDEV	0x03030000  /* no SMC device found (R or D)   */
 #define SMC_CLC_DECL_NOSMCDDEV	0x03030001  /* no SMC-D device found	      */
 #define SMC_CLC_DECL_NOSMCRDEV	0x03030002  /* no SMC-R device found	      */
 #define SMC_CLC_DECL_MODEUNSUPP	0x03040000  /* smc modes do not match (R or D)*/
 #define SMC_CLC_DECL_RMBE_EC	0x03050000  /* peer has eyecatcher in RMBE    */
 #define SMC_CLC_DECL_OPTUNSUPP	0x03060000  /* fastopen sockopt not supported */
 #define SMC_CLC_DECL_DIFFPREFIX	0x03070000  /* IP prefix / subnet mismatch    */
 #define SMC_CLC_DECL_GETVLANERR	0x03080000  /* err to get vlan id of ip device*/
 #define SMC_CLC_DECL_ISMVLANERR	0x03090000  /* err to reg vlan id on ism dev  */
 #define SMC_CLC_DECL_NOACTLINK	0x030a0000  /* no active smc-r link in lgr    */
 #define SMC_CLC_DECL_NOSRVLINK	0x030b0000  /* SMC-R link from srv not found  */
 #define SMC_CLC_DECL_VERSMISMAT	0x030c0000  /* SMC version mismatch	      */
 #define SMC_CLC_DECL_MAX_DMB	0x030d0000  /* SMC-D DMB limit exceeded       */
 #define SMC_CLC_DECL_SYNCERR	0x04000000  /* synchronization error          */
 #define SMC_CLC_DECL_PEERDECL	0x05000000  /* peer declined during handshake */
 #define SMC_CLC_DECL_INTERR	0x09990000  /* internal error		      */
 #define SMC_CLC_DECL_ERR_RTOK	0x09990001  /*	 rtoken handling failed       */
 #define SMC_CLC_DECL_ERR_RDYLNK	0x09990002  /*	 ib ready link failed	      */
 #define SMC_CLC_DECL_ERR_REGRMB	0x09990003  /*	 reg rmb failed		      */

 #define SMC_FIRST_CONTACT_MASK	0b10	/* first contact bit within typev2 */

 struct smc_clc_msg_hdr {	/* header1 of clc messages */
 	u8 eyecatcher[4];	/* eye catcher */
 	u8 type;		/* proposal / accept / confirm / decline */
 	__be16 length;
 #if defined(__BIG_ENDIAN_BITFIELD)
 	u8 version : 4,
 	   typev2  : 2,
 	   typev1  : 2;
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 	u8 typev1  : 2,
 	   typev2  : 2,
 	   version : 4;
 #endif
 } __packed;			/* format defined in RFC7609 */

 struct smc_clc_msg_trail {	/* trailer of clc messages */
 	u8 eyecatcher[4];
 };

 struct smc_clc_msg_local {	/* header2 of clc messages */
 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
 	u8 gid[16];		/* gid of ib_device port */
 	u8 mac[6];		/* mac of ib_device port */
 };

 /* Struct would be 4 byte aligned, but it is used in an array that is sent
  * to peers and must conform to RFC7609, hence we need to use packed here.
  */
 struct smc_clc_ipv6_prefix {
 	struct in6_addr prefix;
 	u8 prefix_len;
 } __packed;			/* format defined in RFC7609 */

 #if defined(__BIG_ENDIAN_BITFIELD)
 struct smc_clc_v2_flag {
 	u8 release : 4,
 	   rsvd    : 3,
 	   seid    : 1;
 };
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 struct smc_clc_v2_flag {
 	u8 seid   : 1,
 	rsvd      : 3,
 	release   : 4;
 };
 #endif

 struct smc_clnt_opts_area_hdr {
 	u8 eid_cnt;		/* number of user defined EIDs */
 	u8 ism_gid_cnt;		/* number of ISMv2 GIDs */
 	u8 reserved1;
 	struct smc_clc_v2_flag flag;
 	u8 reserved2[2];
 	__be16 smcd_v2_ext_offset; /* SMC-Dv2 Extension Offset */
 };

 struct smc_clc_smcd_gid_chid {
 	__be64 gid;		/* ISM GID */
 	__be16 chid;		/* ISMv2 CHID */
 } __packed;		/* format defined in
 			 * IBM Shared Memory Communications Version 2
 			 * (https://www.ibm.com/support/pages/node/6326337)
 			 */

 struct smc_clc_v2_extension {
 	struct smc_clnt_opts_area_hdr hdr;
 	u8 roce[16];		/* RoCEv2 GID */
 	u8 reserved[16];
 	u8 user_eids[0][SMC_MAX_EID_LEN];
 };

 struct smc_clc_msg_proposal_prefix {	/* prefix part of clc proposal message*/
 	__be32 outgoing_subnet;	/* subnet mask */
 	u8 prefix_len;		/* number of significant bits in mask */
 	u8 reserved[2];
 	u8 ipv6_prefixes_cnt;	/* number of IPv6 prefixes in prefix array */
 } __aligned(4);

 struct smc_clc_msg_smcd {	/* SMC-D GID information */
 	struct smc_clc_smcd_gid_chid ism; /* ISM native GID+CHID of requestor */
 	__be16 v2_ext_offset;	/* SMC Version 2 Extension Offset */
 	u8 reserved[28];
 };

 struct smc_clc_smcd_v2_extension {
 	u8 system_eid[SMC_MAX_EID_LEN];
 	u8 reserved[16];
 	struct smc_clc_smcd_gid_chid gidchid[0];
 };

 struct smc_clc_msg_proposal {	/* clc proposal message sent by Linux */
 	struct smc_clc_msg_hdr hdr;
 	struct smc_clc_msg_local lcl;
 	__be16 iparea_offset;	/* offset to IP address information area */
 } __aligned(4);

 #define SMC_CLC_MAX_V6_PREFIX		8

 struct smc_clc_msg_proposal_area {
 	struct smc_clc_msg_proposal		pclc_base;
 	struct smc_clc_msg_smcd			pclc_smcd;
 	struct smc_clc_msg_proposal_prefix	pclc_prfx;
 	struct smc_clc_ipv6_prefix	pclc_prfx_ipv6[SMC_CLC_MAX_V6_PREFIX];
 	struct smc_clc_v2_extension		pclc_v2_ext;
 	struct smc_clc_smcd_v2_extension	pclc_smcd_v2_ext;
 	struct smc_clc_smcd_gid_chid		pclc_gidchids[SMC_MAX_ISM_DEVS];
 	struct smc_clc_msg_trail		pclc_trl;
 };

 struct smcr_clc_msg_accept_confirm {	/* SMCR accept/confirm */
 	struct smc_clc_msg_local lcl;
 	u8 qpn[3];			/* QP number */
 	__be32 rmb_rkey;		/* RMB rkey */
 	u8 rmbe_idx;			/* Index of RMBE in RMB */
 	__be32 rmbe_alert_token;	/* unique connection id */
  #if defined(__BIG_ENDIAN_BITFIELD)
 	u8 rmbe_size : 4,		/* buf size (compressed) */
 	   qp_mtu   : 4;		/* QP mtu */
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 	u8 qp_mtu   : 4,
 	   rmbe_size : 4;
 #endif
 	u8 reserved;
 	__be64 rmb_dma_addr;	/* RMB virtual address */
 	u8 reserved2;
 	u8 psn[3];		/* packet sequence number */
 } __packed;

 struct smcd_clc_msg_accept_confirm_common {	/* SMCD accept/confirm */
 	u64 gid;		/* Sender GID */
 	u64 token;		/* DMB token */
 	u8 dmbe_idx;		/* DMBE index */
 #if defined(__BIG_ENDIAN_BITFIELD)
 	u8 dmbe_size : 4,	/* buf size (compressed) */
 	   reserved3 : 4;
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 	u8 reserved3 : 4,
 	   dmbe_size : 4;
 #endif
 	u16 reserved4;
 	__be32 linkid;		/* Link identifier */
 } __packed;

 #define SMC_CLC_OS_ZOS		1
 #define SMC_CLC_OS_LINUX	2
 #define SMC_CLC_OS_AIX		3

 struct smc_clc_first_contact_ext {
 	u8 reserved1;
 #if defined(__BIG_ENDIAN_BITFIELD)
 	u8 os_type : 4,
 	   release : 4;
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 	u8 release : 4,
 	   os_type : 4;
 #endif
 	u8 reserved2[2];
 	u8 hostname[SMC_MAX_HOSTNAME_LEN];
 };

 struct smc_clc_msg_accept_confirm {	/* clc accept / confirm message */
 	struct smc_clc_msg_hdr hdr;
 	union {
 		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
 		struct { /* SMC-D */
 			struct smcd_clc_msg_accept_confirm_common d0;
 			u32 reserved5[3];
 		};
 	};
 } __packed;			/* format defined in RFC7609 */

 struct smc_clc_msg_accept_confirm_v2 {	/* clc accept / confirm message */
 	struct smc_clc_msg_hdr hdr;
 	union {
 		struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
 		struct { /* SMC-D */
 			struct smcd_clc_msg_accept_confirm_common d0;
 			__be16 chid;
 			u8 eid[SMC_MAX_EID_LEN];
 			u8 reserved5[8];
 		};
 	};
 };

 struct smc_clc_msg_decline {	/* clc decline message */
 	struct smc_clc_msg_hdr hdr;
 	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
 	__be32 peer_diagnosis;	/* diagnosis information */
 #if defined(__BIG_ENDIAN_BITFIELD)
 	u8 os_type  : 4,
 	   reserved : 4;
 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 	u8 reserved : 4,
 	   os_type  : 4;
 #endif
 	u8 reserved2[3];
 	struct smc_clc_msg_trail trl; /* eye catcher "SMCD" or "SMCR" EBCDIC */
 } __aligned(4);

 /* determine start of the prefix area within the proposal message */
 static inline struct smc_clc_msg_proposal_prefix *
 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
 {
 	return (struct smc_clc_msg_proposal_prefix *)
 	       ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
 }

 static inline bool smcr_indicated(int smc_type)
 {
 	return smc_type == SMC_TYPE_R || smc_type == SMC_TYPE_B;
 }

 static inline bool smcd_indicated(int smc_type)
 {
 	return smc_type == SMC_TYPE_D || smc_type == SMC_TYPE_B;
 }

 /* get SMC-D info from proposal message */
 static inline struct smc_clc_msg_smcd *
 smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
 {
 	if (smcd_indicated(prop->hdr.typev1) &&
 	    ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
 		return NULL;

 	return (struct smc_clc_msg_smcd *)(prop + 1);
 }

 static inline struct smc_clc_v2_extension *
 smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop)
 {
 	struct smc_clc_msg_smcd *prop_smcd = smc_get_clc_msg_smcd(prop);

 	if (!prop_smcd || !ntohs(prop_smcd->v2_ext_offset))
 		return NULL;

 	return (struct smc_clc_v2_extension *)
 	       ((u8 *)prop_smcd +
 	       offsetof(struct smc_clc_msg_smcd, v2_ext_offset) +
 	       sizeof(prop_smcd->v2_ext_offset) +
 	       ntohs(prop_smcd->v2_ext_offset));
 }

 static inline struct smc_clc_smcd_v2_extension *
 smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
 {
 	if (!prop_v2ext)
 		return NULL;
 	if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset))
 		return NULL;

 	return (struct smc_clc_smcd_v2_extension *)
 		((u8 *)prop_v2ext +
 		 offsetof(struct smc_clc_v2_extension, hdr) +
 		 offsetof(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset) +
 		 sizeof(prop_v2ext->hdr.smcd_v2_ext_offset) +
 		 ntohs(prop_v2ext->hdr.smcd_v2_ext_offset));
 }

 struct smcd_dev;
 struct smc_init_info;

 int smc_clc_prfx_match(struct socket *clcsock,
 		       struct smc_clc_msg_proposal_prefix *prop);
 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
 		     u8 expected_type, unsigned long timeout);
 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version);
 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_init_info *ini);
 int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
 			 u8 version);
 int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
 			u8 version);
 void smc_clc_init(void) __init;

 #endif
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* Shared Memory Communications over RDMA (SMC-R) and RoCE
	*
	* CLC (connection layer control) handshake over initial TCP socket to
	* prepare for RDMA traffic
	*
	* Copyright IBM Corp. 2016
	*
	* Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com>
	*/

	#ifndef _SMC_CLC_H
	#define _SMC_CLC_H

	#include <rdma/ib_verbs.h>

	#include "smc.h"

	#define SMC_CLC_PROPOSAL 0x01
	#define SMC_CLC_ACCEPT 0x02
	#define SMC_CLC_CONFIRM 0x03
	#define SMC_CLC_DECLINE 0x04

	#define SMC_TYPE_R 0 /* SMC-R only */
	#define SMC_TYPE_D 1 /* SMC-D only */
	#define SMC_TYPE_N 2 /* neither SMC-R nor SMC-D */
	#define SMC_TYPE_B 3 /* SMC-R and SMC-D */
	#define CLC_WAIT_TIME (6 * HZ) /* max. wait time on clcsock */
	#define CLC_WAIT_TIME_SHORT HZ /* short wait time on clcsock */
	#define SMC_CLC_DECL_MEM 0x01010000 /* insufficient memory resources */
	#define SMC_CLC_DECL_TIMEOUT_CL 0x02010000 /* timeout w4 QP confirm link */
	#define SMC_CLC_DECL_TIMEOUT_AL 0x02020000 /* timeout w4 QP add link */
	#define SMC_CLC_DECL_CNFERR 0x03000000 /* configuration error */
	#define SMC_CLC_DECL_PEERNOSMC 0x03010000 /* peer did not indicate SMC */
	#define SMC_CLC_DECL_IPSEC 0x03020000 /* IPsec usage */
	#define SMC_CLC_DECL_NOSMCDEV 0x03030000 /* no SMC device found (R or D) */
	#define SMC_CLC_DECL_NOSMCDDEV 0x03030001 /* no SMC-D device found */
	#define SMC_CLC_DECL_NOSMCRDEV 0x03030002 /* no SMC-R device found */
	#define SMC_CLC_DECL_MODEUNSUPP 0x03040000 /* smc modes do not match (R or D)*/
	#define SMC_CLC_DECL_RMBE_EC 0x03050000 /* peer has eyecatcher in RMBE */
	#define SMC_CLC_DECL_OPTUNSUPP 0x03060000 /* fastopen sockopt not supported */
	#define SMC_CLC_DECL_DIFFPREFIX 0x03070000 /* IP prefix / subnet mismatch */
	#define SMC_CLC_DECL_GETVLANERR 0x03080000 /* err to get vlan id of ip device*/
	#define SMC_CLC_DECL_ISMVLANERR 0x03090000 /* err to reg vlan id on ism dev */
	#define SMC_CLC_DECL_NOACTLINK 0x030a0000 /* no active smc-r link in lgr */
	#define SMC_CLC_DECL_NOSRVLINK 0x030b0000 /* SMC-R link from srv not found */
	#define SMC_CLC_DECL_VERSMISMAT 0x030c0000 /* SMC version mismatch */
	#define SMC_CLC_DECL_MAX_DMB 0x030d0000 /* SMC-D DMB limit exceeded */
	#define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */
	#define SMC_CLC_DECL_PEERDECL 0x05000000 /* peer declined during handshake */
	#define SMC_CLC_DECL_INTERR 0x09990000 /* internal error */
	#define SMC_CLC_DECL_ERR_RTOK 0x09990001 /* rtoken handling failed */
	#define SMC_CLC_DECL_ERR_RDYLNK 0x09990002 /* ib ready link failed */
	#define SMC_CLC_DECL_ERR_REGRMB 0x09990003 /* reg rmb failed */

	#define SMC_FIRST_CONTACT_MASK 0b10 /* first contact bit within typev2 */

	struct smc_clc_msg_hdr { /* header1 of clc messages */
	u8 eyecatcher[4]; /* eye catcher */
	u8 type; /* proposal / accept / confirm / decline */
	__be16 length;
	#if defined(__BIG_ENDIAN_BITFIELD)
	u8 version : 4,
	typev2 : 2,
	typev1 : 2;
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	u8 typev1 : 2,
	typev2 : 2,
	version : 4;
	#endif
	} __packed; /* format defined in RFC7609 */

	struct smc_clc_msg_trail { /* trailer of clc messages */
	u8 eyecatcher[4];
	};

	struct smc_clc_msg_local { /* header2 of clc messages */
	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
	u8 gid[16]; /* gid of ib_device port */
	u8 mac[6]; /* mac of ib_device port */
	};

	/* Struct would be 4 byte aligned, but it is used in an array that is sent
	* to peers and must conform to RFC7609, hence we need to use packed here.
	*/
	struct smc_clc_ipv6_prefix {
	struct in6_addr prefix;
	u8 prefix_len;
	} __packed; /* format defined in RFC7609 */

	#if defined(__BIG_ENDIAN_BITFIELD)
	struct smc_clc_v2_flag {
	u8 release : 4,
	rsvd : 3,
	seid : 1;
	};
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	struct smc_clc_v2_flag {
	u8 seid : 1,
	rsvd : 3,
	release : 4;
	};
	#endif

	struct smc_clnt_opts_area_hdr {
	u8 eid_cnt; /* number of user defined EIDs */
	u8 ism_gid_cnt; /* number of ISMv2 GIDs */
	u8 reserved1;
	struct smc_clc_v2_flag flag;
	u8 reserved2[2];
	__be16 smcd_v2_ext_offset; /* SMC-Dv2 Extension Offset */
	};

	struct smc_clc_smcd_gid_chid {
	__be64 gid; /* ISM GID */
	__be16 chid; /* ISMv2 CHID */
	} __packed; /* format defined in
	* IBM Shared Memory Communications Version 2
	* (https://www.ibm.com/support/pages/node/6326337)
	*/

	struct smc_clc_v2_extension {
	struct smc_clnt_opts_area_hdr hdr;
	u8 roce[16]; /* RoCEv2 GID */
	u8 reserved[16];
	u8 user_eids[0][SMC_MAX_EID_LEN];
	};

	struct smc_clc_msg_proposal_prefix { /* prefix part of clc proposal message*/
	__be32 outgoing_subnet; /* subnet mask */
	u8 prefix_len; /* number of significant bits in mask */
	u8 reserved[2];
	u8 ipv6_prefixes_cnt; /* number of IPv6 prefixes in prefix array */
	} __aligned(4);

	struct smc_clc_msg_smcd { /* SMC-D GID information */
	struct smc_clc_smcd_gid_chid ism; /* ISM native GID+CHID of requestor */
	__be16 v2_ext_offset; /* SMC Version 2 Extension Offset */
	u8 reserved[28];
	};

	struct smc_clc_smcd_v2_extension {
	u8 system_eid[SMC_MAX_EID_LEN];
	u8 reserved[16];
	struct smc_clc_smcd_gid_chid gidchid[0];
	};

	struct smc_clc_msg_proposal { /* clc proposal message sent by Linux */
	struct smc_clc_msg_hdr hdr;
	struct smc_clc_msg_local lcl;
	__be16 iparea_offset; /* offset to IP address information area */
	} __aligned(4);

	#define SMC_CLC_MAX_V6_PREFIX 8

	struct smc_clc_msg_proposal_area {
	struct smc_clc_msg_proposal pclc_base;
	struct smc_clc_msg_smcd pclc_smcd;
	struct smc_clc_msg_proposal_prefix pclc_prfx;
	struct smc_clc_ipv6_prefix pclc_prfx_ipv6[SMC_CLC_MAX_V6_PREFIX];
	struct smc_clc_v2_extension pclc_v2_ext;
	struct smc_clc_smcd_v2_extension pclc_smcd_v2_ext;
	struct smc_clc_smcd_gid_chid pclc_gidchids[SMC_MAX_ISM_DEVS];
	struct smc_clc_msg_trail pclc_trl;
	};

	struct smcr_clc_msg_accept_confirm { /* SMCR accept/confirm */
	struct smc_clc_msg_local lcl;
	u8 qpn[3]; /* QP number */
	__be32 rmb_rkey; /* RMB rkey */
	u8 rmbe_idx; /* Index of RMBE in RMB */
	__be32 rmbe_alert_token; /* unique connection id */
	#if defined(__BIG_ENDIAN_BITFIELD)
	u8 rmbe_size : 4, /* buf size (compressed) */
	qp_mtu : 4; /* QP mtu */
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	u8 qp_mtu : 4,
	rmbe_size : 4;
	#endif
	u8 reserved;
	__be64 rmb_dma_addr; /* RMB virtual address */
	u8 reserved2;
	u8 psn[3]; /* packet sequence number */
	} __packed;

	struct smcd_clc_msg_accept_confirm_common { /* SMCD accept/confirm */
	u64 gid; /* Sender GID */
	u64 token; /* DMB token */
	u8 dmbe_idx; /* DMBE index */
	#if defined(__BIG_ENDIAN_BITFIELD)
	u8 dmbe_size : 4, /* buf size (compressed) */
	reserved3 : 4;
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	u8 reserved3 : 4,
	dmbe_size : 4;
	#endif
	u16 reserved4;
	__be32 linkid; /* Link identifier */
	} __packed;

	#define SMC_CLC_OS_ZOS 1
	#define SMC_CLC_OS_LINUX 2
	#define SMC_CLC_OS_AIX 3

	struct smc_clc_first_contact_ext {
	u8 reserved1;
	#if defined(__BIG_ENDIAN_BITFIELD)
	u8 os_type : 4,
	release : 4;
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	u8 release : 4,
	os_type : 4;
	#endif
	u8 reserved2[2];
	u8 hostname[SMC_MAX_HOSTNAME_LEN];
	};

	struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
	struct smc_clc_msg_hdr hdr;
	union {
	struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
	struct { /* SMC-D */
	struct smcd_clc_msg_accept_confirm_common d0;
	u32 reserved5[3];
	};
	};
	} __packed; /* format defined in RFC7609 */

	struct smc_clc_msg_accept_confirm_v2 { /* clc accept / confirm message */
	struct smc_clc_msg_hdr hdr;
	union {
	struct smcr_clc_msg_accept_confirm r0; /* SMC-R */
	struct { /* SMC-D */
	struct smcd_clc_msg_accept_confirm_common d0;
	__be16 chid;
	u8 eid[SMC_MAX_EID_LEN];
	u8 reserved5[8];
	};
	};
	};

	struct smc_clc_msg_decline { /* clc decline message */
	struct smc_clc_msg_hdr hdr;
	u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
	__be32 peer_diagnosis; /* diagnosis information */
	#if defined(__BIG_ENDIAN_BITFIELD)
	u8 os_type : 4,
	reserved : 4;
	#elif defined(__LITTLE_ENDIAN_BITFIELD)
	u8 reserved : 4,
	os_type : 4;
	#endif
	u8 reserved2[3];
	struct smc_clc_msg_trail trl; /* eye catcher "SMCD" or "SMCR" EBCDIC */
	} __aligned(4);

	/* determine start of the prefix area within the proposal message */
	static inline struct smc_clc_msg_proposal_prefix *
	smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
	{
	return (struct smc_clc_msg_proposal_prefix *)
	((u8 )pclc + sizeof(pclc) + ntohs(pclc->iparea_offset));
	}

	static inline bool smcr_indicated(int smc_type)
	{
	return smc_type == SMC_TYPE_R \|\| smc_type == SMC_TYPE_B;
	}

	static inline bool smcd_indicated(int smc_type)
	{
	return smc_type == SMC_TYPE_D \|\| smc_type == SMC_TYPE_B;
	}

	/* get SMC-D info from proposal message */
	static inline struct smc_clc_msg_smcd *
	smc_get_clc_msg_smcd(struct smc_clc_msg_proposal *prop)
	{
	if (smcd_indicated(prop->hdr.typev1) &&
	ntohs(prop->iparea_offset) != sizeof(struct smc_clc_msg_smcd))
	return NULL;

	return (struct smc_clc_msg_smcd *)(prop + 1);
	}

	static inline struct smc_clc_v2_extension *
	smc_get_clc_v2_ext(struct smc_clc_msg_proposal *prop)
	{
	struct smc_clc_msg_smcd *prop_smcd = smc_get_clc_msg_smcd(prop);

	if (!prop_smcd \|\| !ntohs(prop_smcd->v2_ext_offset))
	return NULL;

	return (struct smc_clc_v2_extension *)
	((u8 *)prop_smcd +
	offsetof(struct smc_clc_msg_smcd, v2_ext_offset) +
	sizeof(prop_smcd->v2_ext_offset) +
	ntohs(prop_smcd->v2_ext_offset));
	}

	static inline struct smc_clc_smcd_v2_extension *
	smc_get_clc_smcd_v2_ext(struct smc_clc_v2_extension *prop_v2ext)
	{
	if (!prop_v2ext)
	return NULL;
	if (!ntohs(prop_v2ext->hdr.smcd_v2_ext_offset))
	return NULL;

	return (struct smc_clc_smcd_v2_extension *)
	((u8 *)prop_v2ext +
	offsetof(struct smc_clc_v2_extension, hdr) +
	offsetof(struct smc_clnt_opts_area_hdr, smcd_v2_ext_offset) +
	sizeof(prop_v2ext->hdr.smcd_v2_ext_offset) +
	ntohs(prop_v2ext->hdr.smcd_v2_ext_offset));
	}

	struct smcd_dev;
	struct smc_init_info;

	int smc_clc_prfx_match(struct socket *clcsock,
	struct smc_clc_msg_proposal_prefix *prop);
	int smc_clc_wait_msg(struct smc_sock smc, void buf, int buflen,
	u8 expected_type, unsigned long timeout);
	int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, u8 version);
	int smc_clc_send_proposal(struct smc_sock smc, struct smc_init_info ini);
	int smc_clc_send_confirm(struct smc_sock *smc, bool clnt_first_contact,
	u8 version);
	int smc_clc_send_accept(struct smc_sock *smc, bool srv_first_contact,
	u8 version);
	void smc_clc_init(void) __init;

	#endif