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 SMC_V1 1 /* SMC version V1 */ 22 #define SMC_V2 2 /* SMC version V2 */ 23 #define SMC_RELEASE 0 24 25 #define SMCPROTO_SMC 0 /* SMC protocol, IPv4 */ 26 #define SMCPROTO_SMC6 1 /* SMC protocol, IPv6 */ 27 28 #define SMC_MAX_ISM_DEVS 8 /* max # of proposed non-native ISM 29 * devices 30 */ 31 32 extern struct proto smc_proto; 33 extern struct proto smc_proto6; 34 35 #ifdef ATOMIC64_INIT 36 #define KERNEL_HAS_ATOMIC64 37 #endif 38 39 enum smc_state { /* possible states of an SMC socket */ 40 SMC_ACTIVE = 1, 41 SMC_INIT = 2, 42 SMC_CLOSED = 7, 43 SMC_LISTEN = 10, 44 /* normal close */ 45 SMC_PEERCLOSEWAIT1 = 20, 46 SMC_PEERCLOSEWAIT2 = 21, 47 SMC_APPFINCLOSEWAIT = 24, 48 SMC_APPCLOSEWAIT1 = 22, 49 SMC_APPCLOSEWAIT2 = 23, 50 SMC_PEERFINCLOSEWAIT = 25, 51 /* abnormal close */ 52 SMC_PEERABORTWAIT = 26, 53 SMC_PROCESSABORT = 27, 54 }; 55 56 struct smc_link_group; 57 58 struct smc_wr_rx_hdr { /* common prefix part of LLC and CDC to demultiplex */ 59 union { 60 u8 type; 61 #if defined(__BIG_ENDIAN_BITFIELD) 62 struct { 63 u8 llc_version:4, 64 llc_type:4; 65 }; 66 #elif defined(__LITTLE_ENDIAN_BITFIELD) 67 struct { 68 u8 llc_type:4, 69 llc_version:4; 70 }; 71 #endif 72 }; 73 } __aligned(1); 74 75 struct smc_cdc_conn_state_flags { 76 #if defined(__BIG_ENDIAN_BITFIELD) 77 u8 peer_done_writing : 1; /* Sending done indicator */ 78 u8 peer_conn_closed : 1; /* Peer connection closed indicator */ 79 u8 peer_conn_abort : 1; /* Abnormal close indicator */ 80 u8 reserved : 5; 81 #elif defined(__LITTLE_ENDIAN_BITFIELD) 82 u8 reserved : 5; 83 u8 peer_conn_abort : 1; 84 u8 peer_conn_closed : 1; 85 u8 peer_done_writing : 1; 86 #endif 87 }; 88 89 struct smc_cdc_producer_flags { 90 #if defined(__BIG_ENDIAN_BITFIELD) 91 u8 write_blocked : 1; /* Writing Blocked, no rx buf space */ 92 u8 urg_data_pending : 1; /* Urgent Data Pending */ 93 u8 urg_data_present : 1; /* Urgent Data Present */ 94 u8 cons_curs_upd_req : 1; /* cursor update requested */ 95 u8 failover_validation : 1;/* message replay due to failover */ 96 u8 reserved : 3; 97 #elif defined(__LITTLE_ENDIAN_BITFIELD) 98 u8 reserved : 3; 99 u8 failover_validation : 1; 100 u8 cons_curs_upd_req : 1; 101 u8 urg_data_present : 1; 102 u8 urg_data_pending : 1; 103 u8 write_blocked : 1; 104 #endif 105 }; 106 107 /* in host byte order */ 108 union smc_host_cursor { /* SMC cursor - an offset in an RMBE */ 109 struct { 110 u16 reserved; 111 u16 wrap; /* window wrap sequence number */ 112 u32 count; /* cursor (= offset) part */ 113 }; 114 #ifdef KERNEL_HAS_ATOMIC64 115 atomic64_t acurs; /* for atomic processing */ 116 #else 117 u64 acurs; /* for atomic processing */ 118 #endif 119 } __aligned(8); 120 121 /* in host byte order, except for flag bitfields in network byte order */ 122 struct smc_host_cdc_msg { /* Connection Data Control message */ 123 struct smc_wr_rx_hdr common; /* .type = 0xFE */ 124 u8 len; /* length = 44 */ 125 u16 seqno; /* connection seq # */ 126 u32 token; /* alert_token */ 127 union smc_host_cursor prod; /* producer cursor */ 128 union smc_host_cursor cons; /* consumer cursor, 129 * piggy backed "ack" 130 */ 131 struct smc_cdc_producer_flags prod_flags; /* conn. tx/rx status */ 132 struct smc_cdc_conn_state_flags conn_state_flags; /* peer conn. status*/ 133 u8 reserved[18]; 134 } __aligned(8); 135 136 enum smc_urg_state { 137 SMC_URG_VALID = 1, /* data present */ 138 SMC_URG_NOTYET = 2, /* data pending */ 139 SMC_URG_READ = 3, /* data was already read */ 140 }; 141 142 struct smc_connection { 143 struct rb_node alert_node; 144 struct smc_link_group *lgr; /* link group of connection */ 145 struct smc_link *lnk; /* assigned SMC-R link */ 146 u32 alert_token_local; /* unique conn. id */ 147 u8 peer_rmbe_idx; /* from tcp handshake */ 148 int peer_rmbe_size; /* size of peer rx buffer */ 149 atomic_t peer_rmbe_space;/* remaining free bytes in peer 150 * rmbe 151 */ 152 int rtoken_idx; /* idx to peer RMB rkey/addr */ 153 154 struct smc_buf_desc *sndbuf_desc; /* send buffer descriptor */ 155 struct smc_buf_desc *rmb_desc; /* RMBE descriptor */ 156 int rmbe_size_short;/* compressed notation */ 157 int rmbe_update_limit; 158 /* lower limit for consumer 159 * cursor update 160 */ 161 162 struct smc_host_cdc_msg local_tx_ctrl; /* host byte order staging 163 * buffer for CDC msg send 164 * .prod cf. TCP snd_nxt 165 * .cons cf. TCP sends ack 166 */ 167 union smc_host_cursor local_tx_ctrl_fin; 168 /* prod crsr - confirmed by peer 169 */ 170 union smc_host_cursor tx_curs_prep; /* tx - prepared data 171 * snd_max..wmem_alloc 172 */ 173 union smc_host_cursor tx_curs_sent; /* tx - sent data 174 * snd_nxt ? 175 */ 176 union smc_host_cursor tx_curs_fin; /* tx - confirmed by peer 177 * snd-wnd-begin ? 178 */ 179 atomic_t sndbuf_space; /* remaining space in sndbuf */ 180 u16 tx_cdc_seq; /* sequence # for CDC send */ 181 u16 tx_cdc_seq_fin; /* sequence # - tx completed */ 182 spinlock_t send_lock; /* protect wr_sends */ 183 atomic_t cdc_pend_tx_wr; /* number of pending tx CDC wqe 184 * - inc when post wqe, 185 * - dec on polled tx cqe 186 */ 187 wait_queue_head_t cdc_pend_tx_wq; /* wakeup on no cdc_pend_tx_wr*/ 188 struct delayed_work tx_work; /* retry of smc_cdc_msg_send */ 189 u32 tx_off; /* base offset in peer rmb */ 190 191 struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl. 192 * .prod cf. TCP rcv_nxt 193 * .cons cf. TCP snd_una 194 */ 195 union smc_host_cursor rx_curs_confirmed; /* confirmed to peer 196 * source of snd_una ? 197 */ 198 union smc_host_cursor urg_curs; /* points at urgent byte */ 199 enum smc_urg_state urg_state; 200 bool urg_tx_pend; /* urgent data staged */ 201 bool urg_rx_skip_pend; 202 /* indicate urgent oob data 203 * read, but previous regular 204 * data still pending 205 */ 206 char urg_rx_byte; /* urgent byte */ 207 atomic_t bytes_to_rcv; /* arrived data, 208 * not yet received 209 */ 210 atomic_t splice_pending; /* number of spliced bytes 211 * pending processing 212 */ 213 #ifndef KERNEL_HAS_ATOMIC64 214 spinlock_t acurs_lock; /* protect cursors */ 215 #endif 216 struct work_struct close_work; /* peer sent some closing */ 217 struct work_struct abort_work; /* abort the connection */ 218 struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */ 219 u8 rx_off; /* receive offset: 220 * 0 for SMC-R, 32 for SMC-D 221 */ 222 u64 peer_token; /* SMC-D token of peer */ 223 u8 killed : 1; /* abnormal termination */ 224 u8 freed : 1; /* normal termiation */ 225 u8 out_of_sync : 1; /* out of sync with peer */ 226 }; 227 228 struct smc_sock { /* smc sock container */ 229 struct sock sk; 230 struct socket *clcsock; /* internal tcp socket */ 231 void (*clcsk_data_ready)(struct sock *sk); 232 /* original data_ready fct. **/ 233 struct smc_connection conn; /* smc connection */ 234 struct smc_sock *listen_smc; /* listen parent */ 235 struct work_struct connect_work; /* handle non-blocking connect*/ 236 struct work_struct tcp_listen_work;/* handle tcp socket accepts */ 237 struct work_struct smc_listen_work;/* prepare new accept socket */ 238 struct list_head accept_q; /* sockets to be accepted */ 239 spinlock_t accept_q_lock; /* protects accept_q */ 240 bool use_fallback; /* fallback to tcp */ 241 int fallback_rsn; /* reason for fallback */ 242 u32 peer_diagnosis; /* decline reason from peer */ 243 int sockopt_defer_accept; 244 /* sockopt TCP_DEFER_ACCEPT 245 * value 246 */ 247 u8 wait_close_tx_prepared : 1; 248 /* shutdown wr or close 249 * started, waiting for unsent 250 * data to be sent 251 */ 252 u8 connect_nonblock : 1; 253 /* non-blocking connect in 254 * flight 255 */ 256 struct mutex clcsock_release_lock; 257 /* protects clcsock of a listen 258 * socket 259 * */ 260 }; 261 262 static inline struct smc_sock *smc_sk(const struct sock *sk) 263 { 264 return (struct smc_sock *)sk; 265 } 266 267 extern struct workqueue_struct *smc_hs_wq; /* wq for handshake work */ 268 extern struct workqueue_struct *smc_close_wq; /* wq for close work */ 269 270 #define SMC_SYSTEMID_LEN 8 271 272 extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ 273 274 #define ntohll(x) be64_to_cpu(x) 275 #define htonll(x) cpu_to_be64(x) 276 277 /* convert an u32 value into network byte order, store it into a 3 byte field */ 278 static inline void hton24(u8 *net, u32 host) 279 { 280 __be32 t; 281 282 t = cpu_to_be32(host); 283 memcpy(net, ((u8 *)&t) + 1, 3); 284 } 285 286 /* convert a received 3 byte field into host byte order*/ 287 static inline u32 ntoh24(u8 *net) 288 { 289 __be32 t = 0; 290 291 memcpy(((u8 *)&t) + 1, net, 3); 292 return be32_to_cpu(t); 293 } 294 295 #ifdef CONFIG_XFRM 296 static inline bool using_ipsec(struct smc_sock *smc) 297 { 298 return (smc->clcsock->sk->sk_policy[0] || 299 smc->clcsock->sk->sk_policy[1]) ? true : false; 300 } 301 #else 302 static inline bool using_ipsec(struct smc_sock *smc) 303 { 304 return false; 305 } 306 #endif 307 308 struct smc_gidlist; 309 310 struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); 311 void smc_close_non_accepted(struct sock *sk); 312 void smc_fill_gid_list(struct smc_link_group *lgr, 313 struct smc_gidlist *gidlist, 314 struct smc_ib_device *known_dev, u8 *known_gid); 315 316 #endif /* __SMC_H */ 317