linux/net/smc/smc_clc.h
Ursula Braun e7b7a64a84 smc: support variable CLC proposal messages
According to RFC7609 [1] the CLC proposal message contains an area of
unknown length for future growth. Additionally it may contain up to
8 IPv6 prefixes. The current version of the SMC-code does not
understand CLC proposal messages using these variable length fields and,
thus, is incompatible with SMC implementations in other operating
systems.

This patch makes sure, SMC understands incoming CLC proposals
* with arbitrary length values for future growth
* with up to 8 IPv6 prefixes

[1] SMC-R Informational RFC: http://www.rfc-editor.org/info/rfc7609

Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Reviewed-by: Hans Wippel <hwippel@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-07 15:03:12 -05:00

139 lines
4.6 KiB
C

/* 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
/* eye catcher "SMCR" EBCDIC for CLC messages */
static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'};
#define SMC_CLC_V1 0x1 /* SMC version */
#define CLC_WAIT_TIME (6 * HZ) /* max. wait time on clcsock */
#define SMC_CLC_DECL_MEM 0x01010000 /* insufficient memory resources */
#define SMC_CLC_DECL_TIMEOUT 0x02000000 /* timeout */
#define SMC_CLC_DECL_CNFERR 0x03000000 /* configuration error */
#define SMC_CLC_DECL_IPSEC 0x03030000 /* IPsec usage */
#define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */
#define SMC_CLC_DECL_REPLY 0x06000000 /* reply to a received decline */
#define SMC_CLC_DECL_INTERR 0x99990000 /* internal error */
#define SMC_CLC_DECL_TCL 0x02040000 /* timeout w4 QP confirm */
#define SMC_CLC_DECL_SEND 0x07000000 /* sending problem */
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,
flag : 1,
rsvd : 3;
#elif defined(__LITTLE_ENDIAN_BITFIELD)
u8 rsvd : 3,
flag : 1,
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 smc_clc_ipv6_prefix {
u8 prefix[4];
u8 prefix_len;
} __packed;
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_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_PROPOSAL_MAX_OFFSET 0x28
#define SMC_CLC_PROPOSAL_MAX_PREFIX (8 * sizeof(struct smc_clc_ipv6_prefix))
#define SMC_CLC_MAX_LEN (sizeof(struct smc_clc_msg_proposal) + \
SMC_CLC_PROPOSAL_MAX_OFFSET + \
SMC_CLC_PROPOSAL_MAX_PREFIX + \
sizeof(struct smc_clc_msg_trail))
struct smc_clc_msg_accept_confirm { /* clc accept / confirm message */
struct smc_clc_msg_hdr hdr;
struct smc_clc_msg_local lcl;
u8 qpn[3]; /* QP number */
__be32 rmb_rkey; /* RMB rkey */
u8 conn_idx; /* Connection index, which RMBE in RMB */
__be32 rmbe_alert_token;/* unique connection id */
#if defined(__BIG_ENDIAN_BITFIELD)
u8 rmbe_size : 4, /* RMBE buf size (compressed notation) */
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]; /* initial packet sequence number */
struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
} __packed; /* format defined in RFC7609 */
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 */
u8 reserved2[4];
struct smc_clc_msg_trail trl; /* eye catcher "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));
}
struct smc_sock;
struct smc_ib_device;
int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
u8 expected_type);
int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
int smc_clc_send_proposal(struct smc_sock *smc, struct smc_ib_device *smcibdev,
u8 ibport);
int smc_clc_send_confirm(struct smc_sock *smc);
int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);
#endif