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/genetlink.h> 18 #include <net/sock.h> 19 20 #include "smc_ib.h" 21 22 #define SMC_V1 1 /* SMC version V1 */ 23 #define SMC_V2 2 /* SMC version V2 */ 24 #define SMC_RELEASE 0 25 26 #define SMCPROTO_SMC 0 /* SMC protocol, IPv4 */ 27 #define SMCPROTO_SMC6 1 /* SMC protocol, IPv6 */ 28 29 #define SMC_MAX_ISM_DEVS 8 /* max # of proposed non-native ISM 30 * devices 31 */ 32 #define SMC_AUTOCORKING_DEFAULT_SIZE 0x10000 /* 64K by default */ 33 34 extern struct proto smc_proto; 35 extern struct proto smc_proto6; 36 37 #ifdef ATOMIC64_INIT 38 #define KERNEL_HAS_ATOMIC64 39 #endif 40 41 enum smc_state { /* possible states of an SMC socket */ 42 SMC_ACTIVE = 1, 43 SMC_INIT = 2, 44 SMC_CLOSED = 7, 45 SMC_LISTEN = 10, 46 /* normal close */ 47 SMC_PEERCLOSEWAIT1 = 20, 48 SMC_PEERCLOSEWAIT2 = 21, 49 SMC_APPFINCLOSEWAIT = 24, 50 SMC_APPCLOSEWAIT1 = 22, 51 SMC_APPCLOSEWAIT2 = 23, 52 SMC_PEERFINCLOSEWAIT = 25, 53 /* abnormal close */ 54 SMC_PEERABORTWAIT = 26, 55 SMC_PROCESSABORT = 27, 56 }; 57 58 struct smc_link_group; 59 60 struct smc_wr_rx_hdr { /* common prefix part of LLC and CDC to demultiplex */ 61 union { 62 u8 type; 63 #if defined(__BIG_ENDIAN_BITFIELD) 64 struct { 65 u8 llc_version:4, 66 llc_type:4; 67 }; 68 #elif defined(__LITTLE_ENDIAN_BITFIELD) 69 struct { 70 u8 llc_type:4, 71 llc_version:4; 72 }; 73 #endif 74 }; 75 } __aligned(1); 76 77 struct smc_cdc_conn_state_flags { 78 #if defined(__BIG_ENDIAN_BITFIELD) 79 u8 peer_done_writing : 1; /* Sending done indicator */ 80 u8 peer_conn_closed : 1; /* Peer connection closed indicator */ 81 u8 peer_conn_abort : 1; /* Abnormal close indicator */ 82 u8 reserved : 5; 83 #elif defined(__LITTLE_ENDIAN_BITFIELD) 84 u8 reserved : 5; 85 u8 peer_conn_abort : 1; 86 u8 peer_conn_closed : 1; 87 u8 peer_done_writing : 1; 88 #endif 89 }; 90 91 struct smc_cdc_producer_flags { 92 #if defined(__BIG_ENDIAN_BITFIELD) 93 u8 write_blocked : 1; /* Writing Blocked, no rx buf space */ 94 u8 urg_data_pending : 1; /* Urgent Data Pending */ 95 u8 urg_data_present : 1; /* Urgent Data Present */ 96 u8 cons_curs_upd_req : 1; /* cursor update requested */ 97 u8 failover_validation : 1;/* message replay due to failover */ 98 u8 reserved : 3; 99 #elif defined(__LITTLE_ENDIAN_BITFIELD) 100 u8 reserved : 3; 101 u8 failover_validation : 1; 102 u8 cons_curs_upd_req : 1; 103 u8 urg_data_present : 1; 104 u8 urg_data_pending : 1; 105 u8 write_blocked : 1; 106 #endif 107 }; 108 109 /* in host byte order */ 110 union smc_host_cursor { /* SMC cursor - an offset in an RMBE */ 111 struct { 112 u16 reserved; 113 u16 wrap; /* window wrap sequence number */ 114 u32 count; /* cursor (= offset) part */ 115 }; 116 #ifdef KERNEL_HAS_ATOMIC64 117 atomic64_t acurs; /* for atomic processing */ 118 #else 119 u64 acurs; /* for atomic processing */ 120 #endif 121 } __aligned(8); 122 123 /* in host byte order, except for flag bitfields in network byte order */ 124 struct smc_host_cdc_msg { /* Connection Data Control message */ 125 struct smc_wr_rx_hdr common; /* .type = 0xFE */ 126 u8 len; /* length = 44 */ 127 u16 seqno; /* connection seq # */ 128 u32 token; /* alert_token */ 129 union smc_host_cursor prod; /* producer cursor */ 130 union smc_host_cursor cons; /* consumer cursor, 131 * piggy backed "ack" 132 */ 133 struct smc_cdc_producer_flags prod_flags; /* conn. tx/rx status */ 134 struct smc_cdc_conn_state_flags conn_state_flags; /* peer conn. status*/ 135 u8 reserved[18]; 136 } __aligned(8); 137 138 enum smc_urg_state { 139 SMC_URG_VALID = 1, /* data present */ 140 SMC_URG_NOTYET = 2, /* data pending */ 141 SMC_URG_READ = 3, /* data was already read */ 142 }; 143 144 struct smc_mark_woken { 145 bool woken; 146 void *key; 147 wait_queue_entry_t wait_entry; 148 }; 149 150 struct smc_connection { 151 struct rb_node alert_node; 152 struct smc_link_group *lgr; /* link group of connection */ 153 struct smc_link *lnk; /* assigned SMC-R link */ 154 u32 alert_token_local; /* unique conn. id */ 155 u8 peer_rmbe_idx; /* from tcp handshake */ 156 int peer_rmbe_size; /* size of peer rx buffer */ 157 atomic_t peer_rmbe_space;/* remaining free bytes in peer 158 * rmbe 159 */ 160 int rtoken_idx; /* idx to peer RMB rkey/addr */ 161 162 struct smc_buf_desc *sndbuf_desc; /* send buffer descriptor */ 163 struct smc_buf_desc *rmb_desc; /* RMBE descriptor */ 164 int rmbe_size_short;/* compressed notation */ 165 int rmbe_update_limit; 166 /* lower limit for consumer 167 * cursor update 168 */ 169 170 struct smc_host_cdc_msg local_tx_ctrl; /* host byte order staging 171 * buffer for CDC msg send 172 * .prod cf. TCP snd_nxt 173 * .cons cf. TCP sends ack 174 */ 175 union smc_host_cursor local_tx_ctrl_fin; 176 /* prod crsr - confirmed by peer 177 */ 178 union smc_host_cursor tx_curs_prep; /* tx - prepared data 179 * snd_max..wmem_alloc 180 */ 181 union smc_host_cursor tx_curs_sent; /* tx - sent data 182 * snd_nxt ? 183 */ 184 union smc_host_cursor tx_curs_fin; /* tx - confirmed by peer 185 * snd-wnd-begin ? 186 */ 187 atomic_t sndbuf_space; /* remaining space in sndbuf */ 188 u16 tx_cdc_seq; /* sequence # for CDC send */ 189 u16 tx_cdc_seq_fin; /* sequence # - tx completed */ 190 spinlock_t send_lock; /* protect wr_sends */ 191 atomic_t cdc_pend_tx_wr; /* number of pending tx CDC wqe 192 * - inc when post wqe, 193 * - dec on polled tx cqe 194 */ 195 wait_queue_head_t cdc_pend_tx_wq; /* wakeup on no cdc_pend_tx_wr*/ 196 atomic_t tx_pushing; /* nr_threads trying tx push */ 197 struct delayed_work tx_work; /* retry of smc_cdc_msg_send */ 198 u32 tx_off; /* base offset in peer rmb */ 199 200 struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl. 201 * .prod cf. TCP rcv_nxt 202 * .cons cf. TCP snd_una 203 */ 204 union smc_host_cursor rx_curs_confirmed; /* confirmed to peer 205 * source of snd_una ? 206 */ 207 union smc_host_cursor urg_curs; /* points at urgent byte */ 208 enum smc_urg_state urg_state; 209 bool urg_tx_pend; /* urgent data staged */ 210 bool urg_rx_skip_pend; 211 /* indicate urgent oob data 212 * read, but previous regular 213 * data still pending 214 */ 215 char urg_rx_byte; /* urgent byte */ 216 bool tx_in_release_sock; 217 /* flush pending tx data in 218 * sock release_cb() 219 */ 220 atomic_t bytes_to_rcv; /* arrived data, 221 * not yet received 222 */ 223 atomic_t splice_pending; /* number of spliced bytes 224 * pending processing 225 */ 226 #ifndef KERNEL_HAS_ATOMIC64 227 spinlock_t acurs_lock; /* protect cursors */ 228 #endif 229 struct work_struct close_work; /* peer sent some closing */ 230 struct work_struct abort_work; /* abort the connection */ 231 struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */ 232 u8 rx_off; /* receive offset: 233 * 0 for SMC-R, 32 for SMC-D 234 */ 235 u64 peer_token; /* SMC-D token of peer */ 236 u8 killed : 1; /* abnormal termination */ 237 u8 freed : 1; /* normal termiation */ 238 u8 out_of_sync : 1; /* out of sync with peer */ 239 }; 240 241 struct smc_sock { /* smc sock container */ 242 struct sock sk; 243 struct socket *clcsock; /* internal tcp socket */ 244 void (*clcsk_state_change)(struct sock *sk); 245 /* original stat_change fct. */ 246 void (*clcsk_data_ready)(struct sock *sk); 247 /* original data_ready fct. */ 248 void (*clcsk_write_space)(struct sock *sk); 249 /* original write_space fct. */ 250 void (*clcsk_error_report)(struct sock *sk); 251 /* original error_report fct. */ 252 struct smc_connection conn; /* smc connection */ 253 struct smc_sock *listen_smc; /* listen parent */ 254 struct work_struct connect_work; /* handle non-blocking connect*/ 255 struct work_struct tcp_listen_work;/* handle tcp socket accepts */ 256 struct work_struct smc_listen_work;/* prepare new accept socket */ 257 struct list_head accept_q; /* sockets to be accepted */ 258 spinlock_t accept_q_lock; /* protects accept_q */ 259 bool limit_smc_hs; /* put constraint on handshake */ 260 bool use_fallback; /* fallback to tcp */ 261 int fallback_rsn; /* reason for fallback */ 262 u32 peer_diagnosis; /* decline reason from peer */ 263 atomic_t queued_smc_hs; /* queued smc handshakes */ 264 struct inet_connection_sock_af_ops af_ops; 265 const struct inet_connection_sock_af_ops *ori_af_ops; 266 /* original af ops */ 267 int sockopt_defer_accept; 268 /* sockopt TCP_DEFER_ACCEPT 269 * value 270 */ 271 u8 wait_close_tx_prepared : 1; 272 /* shutdown wr or close 273 * started, waiting for unsent 274 * data to be sent 275 */ 276 u8 connect_nonblock : 1; 277 /* non-blocking connect in 278 * flight 279 */ 280 struct mutex clcsock_release_lock; 281 /* protects clcsock of a listen 282 * socket 283 * */ 284 }; 285 286 #define smc_sk(ptr) container_of_const(ptr, struct smc_sock, sk) 287 288 static inline void smc_init_saved_callbacks(struct smc_sock *smc) 289 { 290 smc->clcsk_state_change = NULL; 291 smc->clcsk_data_ready = NULL; 292 smc->clcsk_write_space = NULL; 293 smc->clcsk_error_report = NULL; 294 } 295 296 static inline struct smc_sock *smc_clcsock_user_data(const struct sock *clcsk) 297 { 298 return (struct smc_sock *) 299 ((uintptr_t)clcsk->sk_user_data & ~SK_USER_DATA_NOCOPY); 300 } 301 302 /* save target_cb in saved_cb, and replace target_cb with new_cb */ 303 static inline void smc_clcsock_replace_cb(void (**target_cb)(struct sock *), 304 void (*new_cb)(struct sock *), 305 void (**saved_cb)(struct sock *)) 306 { 307 /* only save once */ 308 if (!*saved_cb) 309 *saved_cb = *target_cb; 310 *target_cb = new_cb; 311 } 312 313 /* restore target_cb to saved_cb, and reset saved_cb to NULL */ 314 static inline void smc_clcsock_restore_cb(void (**target_cb)(struct sock *), 315 void (**saved_cb)(struct sock *)) 316 { 317 if (!*saved_cb) 318 return; 319 *target_cb = *saved_cb; 320 *saved_cb = NULL; 321 } 322 323 extern struct workqueue_struct *smc_hs_wq; /* wq for handshake work */ 324 extern struct workqueue_struct *smc_close_wq; /* wq for close work */ 325 326 #define SMC_SYSTEMID_LEN 8 327 328 extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ 329 330 #define ntohll(x) be64_to_cpu(x) 331 #define htonll(x) cpu_to_be64(x) 332 333 /* convert an u32 value into network byte order, store it into a 3 byte field */ 334 static inline void hton24(u8 *net, u32 host) 335 { 336 __be32 t; 337 338 t = cpu_to_be32(host); 339 memcpy(net, ((u8 *)&t) + 1, 3); 340 } 341 342 /* convert a received 3 byte field into host byte order*/ 343 static inline u32 ntoh24(u8 *net) 344 { 345 __be32 t = 0; 346 347 memcpy(((u8 *)&t) + 1, net, 3); 348 return be32_to_cpu(t); 349 } 350 351 #ifdef CONFIG_XFRM 352 static inline bool using_ipsec(struct smc_sock *smc) 353 { 354 return (smc->clcsock->sk->sk_policy[0] || 355 smc->clcsock->sk->sk_policy[1]) ? true : false; 356 } 357 #else 358 static inline bool using_ipsec(struct smc_sock *smc) 359 { 360 return false; 361 } 362 #endif 363 364 struct smc_gidlist; 365 366 struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); 367 void smc_close_non_accepted(struct sock *sk); 368 void smc_fill_gid_list(struct smc_link_group *lgr, 369 struct smc_gidlist *gidlist, 370 struct smc_ib_device *known_dev, u8 *known_gid); 371 372 /* smc handshake limitation interface for netlink */ 373 int smc_nl_dump_hs_limitation(struct sk_buff *skb, struct netlink_callback *cb); 374 int smc_nl_enable_hs_limitation(struct sk_buff *skb, struct genl_info *info); 375 int smc_nl_disable_hs_limitation(struct sk_buff *skb, struct genl_info *info); 376 377 #endif /* __SMC_H */ 378