net/smc/smc_clc.h

   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_CLC_V1              0x1             /* SMC version                */
  26 #define CLC_WAIT_TIME           (6 * HZ)        /* max. wait time on clcsock  */
  27 #define SMC_CLC_DECL_MEM        0x01010000  /* insufficient memory resources  */
  28 #define SMC_CLC_DECL_TIMEOUT    0x02000000  /* timeout                        */
  29 #define SMC_CLC_DECL_CNFERR     0x03000000  /* configuration error            */
  30 #define SMC_CLC_DECL_IPSEC      0x03030000  /* IPsec usage                    */
  31 #define SMC_CLC_DECL_SYNCERR    0x04000000  /* synchronization error          */
  32 #define SMC_CLC_DECL_REPLY      0x06000000  /* reply to a received decline    */
  33 #define SMC_CLC_DECL_INTERR     0x99990000  /* internal error                 */
  34 #define SMC_CLC_DECL_TCL        0x02040000  /* timeout w4 QP confirm          */
  35 #define SMC_CLC_DECL_SEND       0x07000000  /* sending problem                */
  36 #define SMC_CLC_DECL_RMBE_EC    0x08000000  /* peer has eyecatcher in RMBE    */
  37
  38 struct smc_clc_msg_hdr {        /* header1 of clc messages */
  39         u8 eyecatcher[4];       /* eye catcher */
  40         u8 type;                /* proposal / accept / confirm / decline */
  41         __be16 length;
  42 #if defined(__BIG_ENDIAN_BITFIELD)
  43         u8 version : 4,
  44            flag    : 1,
  45            rsvd    : 3;
  46 #elif defined(__LITTLE_ENDIAN_BITFIELD)
  47         u8 rsvd    : 3,
  48            flag    : 1,
  49            version : 4;
  50 #endif
  51 } __packed;                     /* format defined in RFC7609 */
  52
  53 struct smc_clc_msg_trail {      /* trailer of clc messages */
  54         u8 eyecatcher[4];
  55 };
  56
  57 struct smc_clc_msg_local {      /* header2 of clc messages */
  58         u8 id_for_peer[SMC_SYSTEMID_LEN]; /* unique system id */
  59         u8 gid[16];             /* gid of ib_device port */
  60         u8 mac[6];              /* mac of ib_device port */
  61 };
  62
  63 #define SMC_CLC_MAX_V6_PREFIX   8
  64
  65 /* Struct would be 4 byte aligned, but it is used in an array that is sent
  66  * to peers and must conform to RFC7609, hence we need to use packed here.
  67  */
  68 struct smc_clc_ipv6_prefix {
  69         struct in6_addr prefix;
  70         u8 prefix_len;
  71 } __packed;                     /* format defined in RFC7609 */
  72
  73 struct smc_clc_msg_proposal_prefix {    /* prefix part of clc proposal message*/
  74         __be32 outgoing_subnet; /* subnet mask */
  75         u8 prefix_len;          /* number of significant bits in mask */
  76         u8 reserved[2];
  77         u8 ipv6_prefixes_cnt;   /* number of IPv6 prefixes in prefix array */
  78 } __aligned(4);
  79
  80 struct smc_clc_msg_proposal {   /* clc proposal message sent by Linux */
  81         struct smc_clc_msg_hdr hdr;
  82         struct smc_clc_msg_local lcl;
  83         __be16 iparea_offset;   /* offset to IP address information area */
  84 } __aligned(4);
  85
  86 #define SMC_CLC_PROPOSAL_MAX_OFFSET     0x28
  87 #define SMC_CLC_PROPOSAL_MAX_PREFIX     (SMC_CLC_MAX_V6_PREFIX * \
  88                                          sizeof(struct smc_clc_ipv6_prefix))
  89 #define SMC_CLC_MAX_LEN         (sizeof(struct smc_clc_msg_proposal) + \
  90                                  SMC_CLC_PROPOSAL_MAX_OFFSET + \
  91                                  sizeof(struct smc_clc_msg_proposal_prefix) + \
  92                                  SMC_CLC_PROPOSAL_MAX_PREFIX + \
  93                                  sizeof(struct smc_clc_msg_trail))
  94
  95 struct smc_clc_msg_accept_confirm {     /* clc accept / confirm message */
  96         struct smc_clc_msg_hdr hdr;
  97         struct smc_clc_msg_local lcl;
  98         u8 qpn[3];              /* QP number */
  99         __be32 rmb_rkey;        /* RMB rkey */
 100         u8 rmbe_idx;            /* Index of RMBE in RMB */
 101         __be32 rmbe_alert_token;/* unique connection id */
 102 #if defined(__BIG_ENDIAN_BITFIELD)
 103         u8 rmbe_size : 4,       /* RMBE buf size (compressed notation) */
 104            qp_mtu   : 4;        /* QP mtu */
 105 #elif defined(__LITTLE_ENDIAN_BITFIELD)
 106         u8 qp_mtu   : 4,
 107            rmbe_size : 4;
 108 #endif
 109         u8 reserved;
 110         __be64 rmb_dma_addr;    /* RMB virtual address */
 111         u8 reserved2;
 112         u8 psn[3];              /* initial packet sequence number */
 113         struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
 114 } __packed;                     /* format defined in RFC7609 */
 115
 116 struct smc_clc_msg_decline {    /* clc decline message */
 117         struct smc_clc_msg_hdr hdr;
 118         u8 id_for_peer[SMC_SYSTEMID_LEN]; /* sender peer_id */
 119         __be32 peer_diagnosis;  /* diagnosis information */
 120         u8 reserved2[4];
 121         struct smc_clc_msg_trail trl; /* eye catcher "SMCR" EBCDIC */
 122 } __aligned(4);
 123
 124 /* determine start of the prefix area within the proposal message */
 125 static inline struct smc_clc_msg_proposal_prefix *
 126 smc_clc_proposal_get_prefix(struct smc_clc_msg_proposal *pclc)
 127 {
 128         return (struct smc_clc_msg_proposal_prefix *)
 129                ((u8 *)pclc + sizeof(*pclc) + ntohs(pclc->iparea_offset));
 130 }
 131
 132 int smc_clc_prfx_match(struct socket *clcsock,
 133                        struct smc_clc_msg_proposal_prefix *prop);
 134 int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
 135                      u8 expected_type);
 136 int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info);
 137 int smc_clc_send_proposal(struct smc_sock *smc, struct smc_ib_device *smcibdev,
 138                           u8 ibport);
 139 int smc_clc_send_confirm(struct smc_sock *smc);
 140 int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact);
 141
 142 #endif