1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Shared Memory Communications over RDMA (SMC-R) and RoCE 4 * 5 * Definitions for the SMC module (socket related) 6 * 7 * Copyright IBM Corp. 2016 8 * 9 * Author(s): Ursula Braun <ubraun@linux.vnet.ibm.com> 10 */ 11 #ifndef __SMC_H 12 #define __SMC_H 13 14 #include <linux/socket.h> 15 #include <linux/types.h> 16 #include <linux/compiler.h> /* __aligned */ 17 #include <net/sock.h> 18 19 #include "smc_ib.h" 20 21 #define SMCPROTO_SMC 0 /* SMC protocol, IPv4 */ 22 #define SMCPROTO_SMC6 1 /* SMC protocol, IPv6 */ 23 24 extern struct proto smc_proto; 25 extern struct proto smc_proto6; 26 27 #ifdef ATOMIC64_INIT 28 #define KERNEL_HAS_ATOMIC64 29 #endif 30 31 enum smc_state { /* possible states of an SMC socket */ 32 SMC_ACTIVE = 1, 33 SMC_INIT = 2, 34 SMC_CLOSED = 7, 35 SMC_LISTEN = 10, 36 /* normal close */ 37 SMC_PEERCLOSEWAIT1 = 20, 38 SMC_PEERCLOSEWAIT2 = 21, 39 SMC_APPFINCLOSEWAIT = 24, 40 SMC_APPCLOSEWAIT1 = 22, 41 SMC_APPCLOSEWAIT2 = 23, 42 SMC_PEERFINCLOSEWAIT = 25, 43 /* abnormal close */ 44 SMC_PEERABORTWAIT = 26, 45 SMC_PROCESSABORT = 27, 46 }; 47 48 struct smc_link_group; 49 50 struct smc_wr_rx_hdr { /* common prefix part of LLC and CDC to demultiplex */ 51 u8 type; 52 } __aligned(1); 53 54 struct smc_cdc_conn_state_flags { 55 #if defined(__BIG_ENDIAN_BITFIELD) 56 u8 peer_done_writing : 1; /* Sending done indicator */ 57 u8 peer_conn_closed : 1; /* Peer connection closed indicator */ 58 u8 peer_conn_abort : 1; /* Abnormal close indicator */ 59 u8 reserved : 5; 60 #elif defined(__LITTLE_ENDIAN_BITFIELD) 61 u8 reserved : 5; 62 u8 peer_conn_abort : 1; 63 u8 peer_conn_closed : 1; 64 u8 peer_done_writing : 1; 65 #endif 66 }; 67 68 struct smc_cdc_producer_flags { 69 #if defined(__BIG_ENDIAN_BITFIELD) 70 u8 write_blocked : 1; /* Writing Blocked, no rx buf space */ 71 u8 urg_data_pending : 1; /* Urgent Data Pending */ 72 u8 urg_data_present : 1; /* Urgent Data Present */ 73 u8 cons_curs_upd_req : 1; /* cursor update requested */ 74 u8 failover_validation : 1;/* message replay due to failover */ 75 u8 reserved : 3; 76 #elif defined(__LITTLE_ENDIAN_BITFIELD) 77 u8 reserved : 3; 78 u8 failover_validation : 1; 79 u8 cons_curs_upd_req : 1; 80 u8 urg_data_present : 1; 81 u8 urg_data_pending : 1; 82 u8 write_blocked : 1; 83 #endif 84 }; 85 86 /* in host byte order */ 87 union smc_host_cursor { /* SMC cursor - an offset in an RMBE */ 88 struct { 89 u16 reserved; 90 u16 wrap; /* window wrap sequence number */ 91 u32 count; /* cursor (= offset) part */ 92 }; 93 #ifdef KERNEL_HAS_ATOMIC64 94 atomic64_t acurs; /* for atomic processing */ 95 #else 96 u64 acurs; /* for atomic processing */ 97 #endif 98 } __aligned(8); 99 100 /* in host byte order, except for flag bitfields in network byte order */ 101 struct smc_host_cdc_msg { /* Connection Data Control message */ 102 struct smc_wr_rx_hdr common; /* .type = 0xFE */ 103 u8 len; /* length = 44 */ 104 u16 seqno; /* connection seq # */ 105 u32 token; /* alert_token */ 106 union smc_host_cursor prod; /* producer cursor */ 107 union smc_host_cursor cons; /* consumer cursor, 108 * piggy backed "ack" 109 */ 110 struct smc_cdc_producer_flags prod_flags; /* conn. tx/rx status */ 111 struct smc_cdc_conn_state_flags conn_state_flags; /* peer conn. status*/ 112 u8 reserved[18]; 113 } __aligned(8); 114 115 enum smc_urg_state { 116 SMC_URG_VALID = 1, /* data present */ 117 SMC_URG_NOTYET = 2, /* data pending */ 118 SMC_URG_READ = 3, /* data was already read */ 119 }; 120 121 struct smc_connection { 122 struct rb_node alert_node; 123 struct smc_link_group *lgr; /* link group of connection */ 124 struct smc_link *lnk; /* assigned SMC-R link */ 125 u32 alert_token_local; /* unique conn. id */ 126 u8 peer_rmbe_idx; /* from tcp handshake */ 127 int peer_rmbe_size; /* size of peer rx buffer */ 128 atomic_t peer_rmbe_space;/* remaining free bytes in peer 129 * rmbe 130 */ 131 int rtoken_idx; /* idx to peer RMB rkey/addr */ 132 133 struct smc_buf_desc *sndbuf_desc; /* send buffer descriptor */ 134 struct smc_buf_desc *rmb_desc; /* RMBE descriptor */ 135 int rmbe_size_short;/* compressed notation */ 136 int rmbe_update_limit; 137 /* lower limit for consumer 138 * cursor update 139 */ 140 141 struct smc_host_cdc_msg local_tx_ctrl; /* host byte order staging 142 * buffer for CDC msg send 143 * .prod cf. TCP snd_nxt 144 * .cons cf. TCP sends ack 145 */ 146 union smc_host_cursor tx_curs_prep; /* tx - prepared data 147 * snd_max..wmem_alloc 148 */ 149 union smc_host_cursor tx_curs_sent; /* tx - sent data 150 * snd_nxt ? 151 */ 152 union smc_host_cursor tx_curs_fin; /* tx - confirmed by peer 153 * snd-wnd-begin ? 154 */ 155 atomic_t sndbuf_space; /* remaining space in sndbuf */ 156 u16 tx_cdc_seq; /* sequence # for CDC send */ 157 spinlock_t send_lock; /* protect wr_sends */ 158 struct delayed_work tx_work; /* retry of smc_cdc_msg_send */ 159 u32 tx_off; /* base offset in peer rmb */ 160 161 struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl. 162 * .prod cf. TCP rcv_nxt 163 * .cons cf. TCP snd_una 164 */ 165 union smc_host_cursor rx_curs_confirmed; /* confirmed to peer 166 * source of snd_una ? 167 */ 168 union smc_host_cursor urg_curs; /* points at urgent byte */ 169 enum smc_urg_state urg_state; 170 bool urg_tx_pend; /* urgent data staged */ 171 bool urg_rx_skip_pend; 172 /* indicate urgent oob data 173 * read, but previous regular 174 * data still pending 175 */ 176 char urg_rx_byte; /* urgent byte */ 177 atomic_t bytes_to_rcv; /* arrived data, 178 * not yet received 179 */ 180 atomic_t splice_pending; /* number of spliced bytes 181 * pending processing 182 */ 183 #ifndef KERNEL_HAS_ATOMIC64 184 spinlock_t acurs_lock; /* protect cursors */ 185 #endif 186 struct work_struct close_work; /* peer sent some closing */ 187 struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */ 188 u8 rx_off; /* receive offset: 189 * 0 for SMC-R, 32 for SMC-D 190 */ 191 u64 peer_token; /* SMC-D token of peer */ 192 u8 killed : 1; /* abnormal termination */ 193 }; 194 195 struct smc_sock { /* smc sock container */ 196 struct sock sk; 197 struct socket *clcsock; /* internal tcp socket */ 198 struct smc_connection conn; /* smc connection */ 199 struct smc_sock *listen_smc; /* listen parent */ 200 struct work_struct connect_work; /* handle non-blocking connect*/ 201 struct work_struct tcp_listen_work;/* handle tcp socket accepts */ 202 struct work_struct smc_listen_work;/* prepare new accept socket */ 203 struct list_head accept_q; /* sockets to be accepted */ 204 spinlock_t accept_q_lock; /* protects accept_q */ 205 bool use_fallback; /* fallback to tcp */ 206 int fallback_rsn; /* reason for fallback */ 207 u32 peer_diagnosis; /* decline reason from peer */ 208 int sockopt_defer_accept; 209 /* sockopt TCP_DEFER_ACCEPT 210 * value 211 */ 212 u8 wait_close_tx_prepared : 1; 213 /* shutdown wr or close 214 * started, waiting for unsent 215 * data to be sent 216 */ 217 u8 connect_nonblock : 1; 218 /* non-blocking connect in 219 * flight 220 */ 221 struct mutex clcsock_release_lock; 222 /* protects clcsock of a listen 223 * socket 224 * */ 225 }; 226 227 static inline struct smc_sock *smc_sk(const struct sock *sk) 228 { 229 return (struct smc_sock *)sk; 230 } 231 232 #define SMC_SYSTEMID_LEN 8 233 234 extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ 235 236 /* convert an u32 value into network byte order, store it into a 3 byte field */ 237 static inline void hton24(u8 *net, u32 host) 238 { 239 __be32 t; 240 241 t = cpu_to_be32(host); 242 memcpy(net, ((u8 *)&t) + 1, 3); 243 } 244 245 /* convert a received 3 byte field into host byte order*/ 246 static inline u32 ntoh24(u8 *net) 247 { 248 __be32 t = 0; 249 250 memcpy(((u8 *)&t) + 1, net, 3); 251 return be32_to_cpu(t); 252 } 253 254 #ifdef CONFIG_XFRM 255 static inline bool using_ipsec(struct smc_sock *smc) 256 { 257 return (smc->clcsock->sk->sk_policy[0] || 258 smc->clcsock->sk->sk_policy[1]) ? true : false; 259 } 260 #else 261 static inline bool using_ipsec(struct smc_sock *smc) 262 { 263 return false; 264 } 265 #endif 266 267 struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); 268 void smc_close_non_accepted(struct sock *sk); 269 270 #endif /* __SMC_H */ 271