1 /* 2 * linux/include/linux/sunrpc/xprt.h 3 * 4 * Declarations for the RPC transport interface. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]> 7 */ 8 9 #ifndef _LINUX_SUNRPC_XPRT_H 10 #define _LINUX_SUNRPC_XPRT_H 11 12 #include <linux/uio.h> 13 #include <linux/socket.h> 14 #include <linux/in.h> 15 #include <linux/ktime.h> 16 #include <linux/kref.h> 17 #include <linux/sunrpc/sched.h> 18 #include <linux/sunrpc/xdr.h> 19 #include <linux/sunrpc/msg_prot.h> 20 21 #ifdef __KERNEL__ 22 23 #define RPC_MIN_SLOT_TABLE (2U) 24 #define RPC_DEF_SLOT_TABLE (16U) 25 #define RPC_MAX_SLOT_TABLE_LIMIT (65536U) 26 #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT 27 28 #define RPC_CWNDSHIFT (8U) 29 #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 30 #define RPC_INITCWND RPC_CWNDSCALE 31 #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 32 #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 33 34 /* 35 * This describes a timeout strategy 36 */ 37 struct rpc_timeout { 38 unsigned long to_initval, /* initial timeout */ 39 to_maxval, /* max timeout */ 40 to_increment; /* if !exponential */ 41 unsigned int to_retries; /* max # of retries */ 42 unsigned char to_exponential; 43 }; 44 45 enum rpc_display_format_t { 46 RPC_DISPLAY_ADDR = 0, 47 RPC_DISPLAY_PORT, 48 RPC_DISPLAY_PROTO, 49 RPC_DISPLAY_HEX_ADDR, 50 RPC_DISPLAY_HEX_PORT, 51 RPC_DISPLAY_NETID, 52 RPC_DISPLAY_MAX, 53 }; 54 55 struct rpc_task; 56 struct rpc_xprt; 57 struct seq_file; 58 struct svc_serv; 59 struct net; 60 61 /* 62 * This describes a complete RPC request 63 */ 64 struct rpc_rqst { 65 /* 66 * This is the user-visible part 67 */ 68 struct rpc_xprt * rq_xprt; /* RPC client */ 69 struct xdr_buf rq_snd_buf; /* send buffer */ 70 struct xdr_buf rq_rcv_buf; /* recv buffer */ 71 72 /* 73 * This is the private part 74 */ 75 struct rpc_task * rq_task; /* RPC task data */ 76 struct rpc_cred * rq_cred; /* Bound cred */ 77 __be32 rq_xid; /* request XID */ 78 int rq_cong; /* has incremented xprt->cong */ 79 u32 rq_seqno; /* gss seq no. used on req. */ 80 int rq_enc_pages_num; 81 struct page **rq_enc_pages; /* scratch pages for use by 82 gss privacy code */ 83 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ 84 struct list_head rq_list; 85 86 void *rq_xprtdata; /* Per-xprt private data */ 87 void *rq_buffer; /* Call XDR encode buffer */ 88 size_t rq_callsize; 89 void *rq_rbuffer; /* Reply XDR decode buffer */ 90 size_t rq_rcvsize; 91 size_t rq_xmit_bytes_sent; /* total bytes sent */ 92 size_t rq_reply_bytes_recvd; /* total reply bytes */ 93 /* received */ 94 95 struct xdr_buf rq_private_buf; /* The receive buffer 96 * used in the softirq. 97 */ 98 unsigned long rq_majortimeo; /* major timeout alarm */ 99 unsigned long rq_timeout; /* Current timeout value */ 100 ktime_t rq_rtt; /* round-trip time */ 101 unsigned int rq_retries; /* # of retries */ 102 unsigned int rq_connect_cookie; 103 /* A cookie used to track the 104 state of the transport 105 connection */ 106 107 /* 108 * Partial send handling 109 */ 110 u32 rq_bytes_sent; /* Bytes we have sent */ 111 112 ktime_t rq_xtime; /* transmit time stamp */ 113 int rq_ntrans; 114 115 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 116 struct list_head rq_bc_list; /* Callback service list */ 117 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 118 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 119 #endif /* CONFIG_SUNRPC_BACKCHANEL */ 120 }; 121 #define rq_svec rq_snd_buf.head 122 #define rq_slen rq_snd_buf.len 123 124 struct rpc_xprt_ops { 125 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 126 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 127 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 128 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 129 void (*rpcbind)(struct rpc_task *task); 130 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 131 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 132 int (*buf_alloc)(struct rpc_task *task); 133 void (*buf_free)(struct rpc_task *task); 134 int (*send_request)(struct rpc_task *task); 135 void (*set_retrans_timeout)(struct rpc_task *task); 136 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 137 void (*release_request)(struct rpc_task *task); 138 void (*close)(struct rpc_xprt *xprt); 139 void (*destroy)(struct rpc_xprt *xprt); 140 void (*set_connect_timeout)(struct rpc_xprt *xprt, 141 unsigned long connect_timeout, 142 unsigned long reconnect_timeout); 143 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 144 int (*enable_swap)(struct rpc_xprt *xprt); 145 void (*disable_swap)(struct rpc_xprt *xprt); 146 void (*inject_disconnect)(struct rpc_xprt *xprt); 147 int (*bc_setup)(struct rpc_xprt *xprt, 148 unsigned int min_reqs); 149 int (*bc_up)(struct svc_serv *serv, struct net *net); 150 size_t (*bc_maxpayload)(struct rpc_xprt *xprt); 151 void (*bc_free_rqst)(struct rpc_rqst *rqst); 152 void (*bc_destroy)(struct rpc_xprt *xprt, 153 unsigned int max_reqs); 154 }; 155 156 /* 157 * RPC transport identifiers 158 * 159 * To preserve compatibility with the historical use of raw IP protocol 160 * id's for transport selection, UDP and TCP identifiers are specified 161 * with the previous values. No such restriction exists for new transports, 162 * except that they may not collide with these values (17 and 6, 163 * respectively). 164 */ 165 #define XPRT_TRANSPORT_BC (1 << 31) 166 enum xprt_transports { 167 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 168 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 169 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 170 XPRT_TRANSPORT_RDMA = 256, 171 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 172 XPRT_TRANSPORT_LOCAL = 257, 173 }; 174 175 struct rpc_xprt { 176 struct kref kref; /* Reference count */ 177 struct rpc_xprt_ops * ops; /* transport methods */ 178 179 const struct rpc_timeout *timeout; /* timeout parms */ 180 struct sockaddr_storage addr; /* server address */ 181 size_t addrlen; /* size of server address */ 182 int prot; /* IP protocol */ 183 184 unsigned long cong; /* current congestion */ 185 unsigned long cwnd; /* congestion window */ 186 187 size_t max_payload; /* largest RPC payload size, 188 in bytes */ 189 unsigned int tsh_size; /* size of transport specific 190 header */ 191 192 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 193 struct rpc_wait_queue sending; /* requests waiting to send */ 194 struct rpc_wait_queue pending; /* requests in flight */ 195 struct rpc_wait_queue backlog; /* waiting for slot */ 196 struct list_head free; /* free slots */ 197 unsigned int max_reqs; /* max number of slots */ 198 unsigned int min_reqs; /* min number of slots */ 199 atomic_t num_reqs; /* total slots */ 200 unsigned long state; /* transport state */ 201 unsigned char resvport : 1; /* use a reserved port */ 202 atomic_t swapper; /* we're swapping over this 203 transport */ 204 unsigned int bind_index; /* bind function index */ 205 206 /* 207 * Multipath 208 */ 209 struct list_head xprt_switch; 210 211 /* 212 * Connection of transports 213 */ 214 unsigned long bind_timeout, 215 reestablish_timeout; 216 unsigned int connect_cookie; /* A cookie that gets bumped 217 every time the transport 218 is reconnected */ 219 220 /* 221 * Disconnection of idle transports 222 */ 223 struct work_struct task_cleanup; 224 struct timer_list timer; 225 unsigned long last_used, 226 idle_timeout, 227 connect_timeout, 228 max_reconnect_timeout; 229 230 /* 231 * Send stuff 232 */ 233 spinlock_t transport_lock; /* lock transport info */ 234 spinlock_t reserve_lock; /* lock slot table */ 235 u32 xid; /* Next XID value to use */ 236 struct rpc_task * snd_task; /* Task blocked in send */ 237 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 238 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 239 struct svc_serv *bc_serv; /* The RPC service which will */ 240 /* process the callback */ 241 int bc_alloc_count; /* Total number of preallocs */ 242 atomic_t bc_free_slots; 243 spinlock_t bc_pa_lock; /* Protects the preallocated 244 * items */ 245 struct list_head bc_pa_list; /* List of preallocated 246 * backchannel rpc_rqst's */ 247 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 248 struct list_head recv; 249 250 struct { 251 unsigned long bind_count, /* total number of binds */ 252 connect_count, /* total number of connects */ 253 connect_start, /* connect start timestamp */ 254 connect_time, /* jiffies waiting for connect */ 255 sends, /* how many complete requests */ 256 recvs, /* how many complete requests */ 257 bad_xids, /* lookup_rqst didn't find XID */ 258 max_slots; /* max rpc_slots used */ 259 260 unsigned long long req_u, /* average requests on the wire */ 261 bklog_u, /* backlog queue utilization */ 262 sending_u, /* send q utilization */ 263 pending_u; /* pend q utilization */ 264 } stat; 265 266 struct net *xprt_net; 267 const char *servername; 268 const char *address_strings[RPC_DISPLAY_MAX]; 269 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 270 struct dentry *debugfs; /* debugfs directory */ 271 atomic_t inject_disconnect; 272 #endif 273 struct rcu_head rcu; 274 }; 275 276 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 277 /* 278 * Backchannel flags 279 */ 280 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 281 /* buffer in use */ 282 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 283 284 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 285 static inline int bc_prealloc(struct rpc_rqst *req) 286 { 287 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 288 } 289 #else 290 static inline int bc_prealloc(struct rpc_rqst *req) 291 { 292 return 0; 293 } 294 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 295 296 #define XPRT_CREATE_INFINITE_SLOTS (1U) 297 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 298 299 struct xprt_create { 300 int ident; /* XPRT_TRANSPORT identifier */ 301 struct net * net; 302 struct sockaddr * srcaddr; /* optional local address */ 303 struct sockaddr * dstaddr; /* remote peer address */ 304 size_t addrlen; 305 const char *servername; 306 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 307 struct rpc_xprt_switch *bc_xps; 308 unsigned int flags; 309 }; 310 311 struct xprt_class { 312 struct list_head list; 313 int ident; /* XPRT_TRANSPORT identifier */ 314 struct rpc_xprt * (*setup)(struct xprt_create *); 315 struct module *owner; 316 char name[32]; 317 }; 318 319 /* 320 * Generic internal transport functions 321 */ 322 struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 323 void xprt_connect(struct rpc_task *task); 324 void xprt_reserve(struct rpc_task *task); 325 void xprt_retry_reserve(struct rpc_task *task); 326 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 327 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 328 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 329 void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 330 bool xprt_prepare_transmit(struct rpc_task *task); 331 void xprt_transmit(struct rpc_task *task); 332 void xprt_end_transmit(struct rpc_task *task); 333 int xprt_adjust_timeout(struct rpc_rqst *req); 334 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 335 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 336 void xprt_release(struct rpc_task *task); 337 struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); 338 void xprt_put(struct rpc_xprt *xprt); 339 struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 340 unsigned int num_prealloc, 341 unsigned int max_req); 342 void xprt_free(struct rpc_xprt *); 343 344 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) 345 { 346 return p + xprt->tsh_size; 347 } 348 349 static inline int 350 xprt_enable_swap(struct rpc_xprt *xprt) 351 { 352 return xprt->ops->enable_swap(xprt); 353 } 354 355 static inline void 356 xprt_disable_swap(struct rpc_xprt *xprt) 357 { 358 xprt->ops->disable_swap(xprt); 359 } 360 361 /* 362 * Transport switch helper functions 363 */ 364 int xprt_register_transport(struct xprt_class *type); 365 int xprt_unregister_transport(struct xprt_class *type); 366 int xprt_load_transport(const char *); 367 void xprt_set_retrans_timeout_def(struct rpc_task *task); 368 void xprt_set_retrans_timeout_rtt(struct rpc_task *task); 369 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 370 void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action); 371 void xprt_write_space(struct rpc_xprt *xprt); 372 void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 373 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 374 void xprt_complete_rqst(struct rpc_task *task, int copied); 375 void xprt_release_rqst_cong(struct rpc_task *task); 376 void xprt_disconnect_done(struct rpc_xprt *xprt); 377 void xprt_force_disconnect(struct rpc_xprt *xprt); 378 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 379 380 bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 381 void xprt_unlock_connect(struct rpc_xprt *, void *); 382 383 /* 384 * Reserved bit positions in xprt->state 385 */ 386 #define XPRT_LOCKED (0) 387 #define XPRT_CONNECTED (1) 388 #define XPRT_CONNECTING (2) 389 #define XPRT_CLOSE_WAIT (3) 390 #define XPRT_BOUND (4) 391 #define XPRT_BINDING (5) 392 #define XPRT_CLOSING (6) 393 #define XPRT_CONGESTED (9) 394 395 static inline void xprt_set_connected(struct rpc_xprt *xprt) 396 { 397 set_bit(XPRT_CONNECTED, &xprt->state); 398 } 399 400 static inline void xprt_clear_connected(struct rpc_xprt *xprt) 401 { 402 clear_bit(XPRT_CONNECTED, &xprt->state); 403 } 404 405 static inline int xprt_connected(struct rpc_xprt *xprt) 406 { 407 return test_bit(XPRT_CONNECTED, &xprt->state); 408 } 409 410 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 411 { 412 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 413 } 414 415 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 416 { 417 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 418 } 419 420 static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 421 { 422 smp_mb__before_atomic(); 423 clear_bit(XPRT_CONNECTING, &xprt->state); 424 smp_mb__after_atomic(); 425 } 426 427 static inline int xprt_connecting(struct rpc_xprt *xprt) 428 { 429 return test_bit(XPRT_CONNECTING, &xprt->state); 430 } 431 432 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 433 { 434 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 435 } 436 437 static inline void xprt_set_bound(struct rpc_xprt *xprt) 438 { 439 test_and_set_bit(XPRT_BOUND, &xprt->state); 440 } 441 442 static inline int xprt_bound(struct rpc_xprt *xprt) 443 { 444 return test_bit(XPRT_BOUND, &xprt->state); 445 } 446 447 static inline void xprt_clear_bound(struct rpc_xprt *xprt) 448 { 449 clear_bit(XPRT_BOUND, &xprt->state); 450 } 451 452 static inline void xprt_clear_binding(struct rpc_xprt *xprt) 453 { 454 smp_mb__before_atomic(); 455 clear_bit(XPRT_BINDING, &xprt->state); 456 smp_mb__after_atomic(); 457 } 458 459 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 460 { 461 return test_and_set_bit(XPRT_BINDING, &xprt->state); 462 } 463 464 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 465 extern unsigned int rpc_inject_disconnect; 466 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 467 { 468 if (!rpc_inject_disconnect) 469 return; 470 if (atomic_dec_return(&xprt->inject_disconnect)) 471 return; 472 atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); 473 xprt->ops->inject_disconnect(xprt); 474 } 475 #else 476 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 477 { 478 } 479 #endif 480 481 #endif /* __KERNEL__*/ 482 483 #endif /* _LINUX_SUNRPC_XPRT_H */ 484