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 u32 alert_token_local; /* unique conn. id */ 125 u8 peer_rmbe_idx; /* from tcp handshake */ 126 int peer_rmbe_size; /* size of peer rx buffer */ 127 atomic_t peer_rmbe_space;/* remaining free bytes in peer 128 * rmbe 129 */ 130 int rtoken_idx; /* idx to peer RMB rkey/addr */ 131 132 struct smc_buf_desc *sndbuf_desc; /* send buffer descriptor */ 133 struct smc_buf_desc *rmb_desc; /* RMBE descriptor */ 134 int rmbe_size_short;/* compressed notation */ 135 int rmbe_update_limit; 136 /* lower limit for consumer 137 * cursor update 138 */ 139 140 struct smc_host_cdc_msg local_tx_ctrl; /* host byte order staging 141 * buffer for CDC msg send 142 * .prod cf. TCP snd_nxt 143 * .cons cf. TCP sends ack 144 */ 145 union smc_host_cursor tx_curs_prep; /* tx - prepared data 146 * snd_max..wmem_alloc 147 */ 148 union smc_host_cursor tx_curs_sent; /* tx - sent data 149 * snd_nxt ? 150 */ 151 union smc_host_cursor tx_curs_fin; /* tx - confirmed by peer 152 * snd-wnd-begin ? 153 */ 154 atomic_t sndbuf_space; /* remaining space in sndbuf */ 155 u16 tx_cdc_seq; /* sequence # for CDC send */ 156 spinlock_t send_lock; /* protect wr_sends */ 157 struct delayed_work tx_work; /* retry of smc_cdc_msg_send */ 158 u32 tx_off; /* base offset in peer rmb */ 159 160 struct smc_host_cdc_msg local_rx_ctrl; /* filled during event_handl. 161 * .prod cf. TCP rcv_nxt 162 * .cons cf. TCP snd_una 163 */ 164 union smc_host_cursor rx_curs_confirmed; /* confirmed to peer 165 * source of snd_una ? 166 */ 167 union smc_host_cursor urg_curs; /* points at urgent byte */ 168 enum smc_urg_state urg_state; 169 bool urg_tx_pend; /* urgent data staged */ 170 bool urg_rx_skip_pend; 171 /* indicate urgent oob data 172 * read, but previous regular 173 * data still pending 174 */ 175 char urg_rx_byte; /* urgent byte */ 176 atomic_t bytes_to_rcv; /* arrived data, 177 * not yet received 178 */ 179 atomic_t splice_pending; /* number of spliced bytes 180 * pending processing 181 */ 182 #ifndef KERNEL_HAS_ATOMIC64 183 spinlock_t acurs_lock; /* protect cursors */ 184 #endif 185 struct work_struct close_work; /* peer sent some closing */ 186 struct tasklet_struct rx_tsklet; /* Receiver tasklet for SMC-D */ 187 u8 rx_off; /* receive offset: 188 * 0 for SMC-R, 32 for SMC-D 189 */ 190 u64 peer_token; /* SMC-D token of peer */ 191 }; 192 193 struct smc_sock { /* smc sock container */ 194 struct sock sk; 195 struct socket *clcsock; /* internal tcp socket */ 196 struct smc_connection conn; /* smc connection */ 197 struct smc_sock *listen_smc; /* listen parent */ 198 struct work_struct connect_work; /* handle non-blocking connect*/ 199 struct work_struct tcp_listen_work;/* handle tcp socket accepts */ 200 struct work_struct smc_listen_work;/* prepare new accept socket */ 201 struct list_head accept_q; /* sockets to be accepted */ 202 spinlock_t accept_q_lock; /* protects accept_q */ 203 bool use_fallback; /* fallback to tcp */ 204 int fallback_rsn; /* reason for fallback */ 205 u32 peer_diagnosis; /* decline reason from peer */ 206 int sockopt_defer_accept; 207 /* sockopt TCP_DEFER_ACCEPT 208 * value 209 */ 210 u8 wait_close_tx_prepared : 1; 211 /* shutdown wr or close 212 * started, waiting for unsent 213 * data to be sent 214 */ 215 u8 connect_nonblock : 1; 216 /* non-blocking connect in 217 * flight 218 */ 219 struct mutex clcsock_release_lock; 220 /* protects clcsock of a listen 221 * socket 222 * */ 223 }; 224 225 static inline struct smc_sock *smc_sk(const struct sock *sk) 226 { 227 return (struct smc_sock *)sk; 228 } 229 230 #define SMC_SYSTEMID_LEN 8 231 232 extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ 233 234 /* convert an u32 value into network byte order, store it into a 3 byte field */ 235 static inline void hton24(u8 *net, u32 host) 236 { 237 __be32 t; 238 239 t = cpu_to_be32(host); 240 memcpy(net, ((u8 *)&t) + 1, 3); 241 } 242 243 /* convert a received 3 byte field into host byte order*/ 244 static inline u32 ntoh24(u8 *net) 245 { 246 __be32 t = 0; 247 248 memcpy(((u8 *)&t) + 1, net, 3); 249 return be32_to_cpu(t); 250 } 251 252 #ifdef CONFIG_XFRM 253 static inline bool using_ipsec(struct smc_sock *smc) 254 { 255 return (smc->clcsock->sk->sk_policy[0] || 256 smc->clcsock->sk->sk_policy[1]) ? true : false; 257 } 258 #else 259 static inline bool using_ipsec(struct smc_sock *smc) 260 { 261 return false; 262 } 263 #endif 264 265 struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock); 266 void smc_close_non_accepted(struct sock *sk); 267 268 #endif /* __SMC_H */ 269