1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * linux/include/linux/sunrpc/xprt.h 4 * 5 * Declarations for the RPC transport interface. 6 * 7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 8 */ 9 10 #ifndef _LINUX_SUNRPC_XPRT_H 11 #define _LINUX_SUNRPC_XPRT_H 12 13 #include <linux/uio.h> 14 #include <linux/socket.h> 15 #include <linux/in.h> 16 #include <linux/ktime.h> 17 #include <linux/kref.h> 18 #include <linux/sunrpc/sched.h> 19 #include <linux/sunrpc/xdr.h> 20 #include <linux/sunrpc/msg_prot.h> 21 22 #define RPC_MIN_SLOT_TABLE (2U) 23 #define RPC_DEF_SLOT_TABLE (16U) 24 #define RPC_MAX_SLOT_TABLE_LIMIT (65536U) 25 #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT 26 27 #define RPC_CWNDSHIFT (8U) 28 #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 29 #define RPC_INITCWND RPC_CWNDSCALE 30 #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 31 #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 32 33 /* 34 * This describes a timeout strategy 35 */ 36 struct rpc_timeout { 37 unsigned long to_initval, /* initial timeout */ 38 to_maxval, /* max timeout */ 39 to_increment; /* if !exponential */ 40 unsigned int to_retries; /* max # of retries */ 41 unsigned char to_exponential; 42 }; 43 44 enum rpc_display_format_t { 45 RPC_DISPLAY_ADDR = 0, 46 RPC_DISPLAY_PORT, 47 RPC_DISPLAY_PROTO, 48 RPC_DISPLAY_HEX_ADDR, 49 RPC_DISPLAY_HEX_PORT, 50 RPC_DISPLAY_NETID, 51 RPC_DISPLAY_MAX, 52 }; 53 54 struct rpc_task; 55 struct rpc_xprt; 56 struct xprt_class; 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 85 union { 86 struct list_head rq_list; /* Slot allocation list */ 87 struct rb_node rq_recv; /* Receive queue */ 88 }; 89 90 struct list_head rq_xmit; /* Send queue */ 91 struct list_head rq_xmit2; /* Send queue */ 92 93 void *rq_buffer; /* Call XDR encode buffer */ 94 size_t rq_callsize; 95 void *rq_rbuffer; /* Reply XDR decode buffer */ 96 size_t rq_rcvsize; 97 size_t rq_xmit_bytes_sent; /* total bytes sent */ 98 size_t rq_reply_bytes_recvd; /* total reply bytes */ 99 /* received */ 100 101 struct xdr_buf rq_private_buf; /* The receive buffer 102 * used in the softirq. 103 */ 104 unsigned long rq_majortimeo; /* major timeout alarm */ 105 unsigned long rq_minortimeo; /* minor timeout alarm */ 106 unsigned long rq_timeout; /* Current timeout value */ 107 ktime_t rq_rtt; /* round-trip time */ 108 unsigned int rq_retries; /* # of retries */ 109 unsigned int rq_connect_cookie; 110 /* A cookie used to track the 111 state of the transport 112 connection */ 113 atomic_t rq_pin; 114 115 /* 116 * Partial send handling 117 */ 118 u32 rq_bytes_sent; /* Bytes we have sent */ 119 120 ktime_t rq_xtime; /* transmit time stamp */ 121 int rq_ntrans; 122 123 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 124 struct list_head rq_bc_list; /* Callback service list */ 125 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 126 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 127 #endif /* CONFIG_SUNRPC_BACKCHANEL */ 128 }; 129 #define rq_svec rq_snd_buf.head 130 #define rq_slen rq_snd_buf.len 131 132 struct rpc_xprt_ops { 133 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 134 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 135 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 136 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 137 void (*free_slot)(struct rpc_xprt *xprt, 138 struct rpc_rqst *req); 139 void (*rpcbind)(struct rpc_task *task); 140 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 141 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 142 int (*buf_alloc)(struct rpc_task *task); 143 void (*buf_free)(struct rpc_task *task); 144 void (*prepare_request)(struct rpc_rqst *req); 145 int (*send_request)(struct rpc_rqst *req); 146 void (*wait_for_reply_request)(struct rpc_task *task); 147 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 148 void (*release_request)(struct rpc_task *task); 149 void (*close)(struct rpc_xprt *xprt); 150 void (*destroy)(struct rpc_xprt *xprt); 151 void (*set_connect_timeout)(struct rpc_xprt *xprt, 152 unsigned long connect_timeout, 153 unsigned long reconnect_timeout); 154 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 155 int (*enable_swap)(struct rpc_xprt *xprt); 156 void (*disable_swap)(struct rpc_xprt *xprt); 157 void (*inject_disconnect)(struct rpc_xprt *xprt); 158 int (*bc_setup)(struct rpc_xprt *xprt, 159 unsigned int min_reqs); 160 size_t (*bc_maxpayload)(struct rpc_xprt *xprt); 161 unsigned int (*bc_num_slots)(struct rpc_xprt *xprt); 162 void (*bc_free_rqst)(struct rpc_rqst *rqst); 163 void (*bc_destroy)(struct rpc_xprt *xprt, 164 unsigned int max_reqs); 165 }; 166 167 /* 168 * RPC transport identifiers 169 * 170 * To preserve compatibility with the historical use of raw IP protocol 171 * id's for transport selection, UDP and TCP identifiers are specified 172 * with the previous values. No such restriction exists for new transports, 173 * except that they may not collide with these values (17 and 6, 174 * respectively). 175 */ 176 #define XPRT_TRANSPORT_BC (1 << 31) 177 enum xprt_transports { 178 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 179 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 180 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 181 XPRT_TRANSPORT_RDMA = 256, 182 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 183 XPRT_TRANSPORT_LOCAL = 257, 184 }; 185 186 struct rpc_sysfs_xprt; 187 struct rpc_xprt { 188 struct kref kref; /* Reference count */ 189 const struct rpc_xprt_ops *ops; /* transport methods */ 190 unsigned int id; /* transport id */ 191 192 const struct rpc_timeout *timeout; /* timeout parms */ 193 struct sockaddr_storage addr; /* server address */ 194 size_t addrlen; /* size of server address */ 195 int prot; /* IP protocol */ 196 197 unsigned long cong; /* current congestion */ 198 unsigned long cwnd; /* congestion window */ 199 200 size_t max_payload; /* largest RPC payload size, 201 in bytes */ 202 203 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 204 struct rpc_wait_queue sending; /* requests waiting to send */ 205 struct rpc_wait_queue pending; /* requests in flight */ 206 struct rpc_wait_queue backlog; /* waiting for slot */ 207 struct list_head free; /* free slots */ 208 unsigned int max_reqs; /* max number of slots */ 209 unsigned int min_reqs; /* min number of slots */ 210 unsigned int num_reqs; /* total slots */ 211 unsigned long state; /* transport state */ 212 unsigned char resvport : 1, /* use a reserved port */ 213 reuseport : 1; /* reuse port on reconnect */ 214 atomic_t swapper; /* we're swapping over this 215 transport */ 216 unsigned int bind_index; /* bind function index */ 217 218 /* 219 * Multipath 220 */ 221 struct list_head xprt_switch; 222 223 /* 224 * Connection of transports 225 */ 226 unsigned long bind_timeout, 227 reestablish_timeout; 228 unsigned int connect_cookie; /* A cookie that gets bumped 229 every time the transport 230 is reconnected */ 231 232 /* 233 * Disconnection of idle transports 234 */ 235 struct work_struct task_cleanup; 236 struct timer_list timer; 237 unsigned long last_used, 238 idle_timeout, 239 connect_timeout, 240 max_reconnect_timeout; 241 242 /* 243 * Send stuff 244 */ 245 atomic_long_t queuelen; 246 spinlock_t transport_lock; /* lock transport info */ 247 spinlock_t reserve_lock; /* lock slot table */ 248 spinlock_t queue_lock; /* send/receive queue lock */ 249 u32 xid; /* Next XID value to use */ 250 struct rpc_task * snd_task; /* Task blocked in send */ 251 252 struct list_head xmit_queue; /* Send queue */ 253 atomic_long_t xmit_queuelen; 254 255 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 256 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 257 struct svc_serv *bc_serv; /* The RPC service which will */ 258 /* process the callback */ 259 unsigned int bc_alloc_max; 260 unsigned int bc_alloc_count; /* Total number of preallocs */ 261 atomic_t bc_slot_count; /* Number of allocated slots */ 262 spinlock_t bc_pa_lock; /* Protects the preallocated 263 * items */ 264 struct list_head bc_pa_list; /* List of preallocated 265 * backchannel rpc_rqst's */ 266 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 267 268 struct rb_root recv_queue; /* Receive queue */ 269 270 struct { 271 unsigned long bind_count, /* total number of binds */ 272 connect_count, /* total number of connects */ 273 connect_start, /* connect start timestamp */ 274 connect_time, /* jiffies waiting for connect */ 275 sends, /* how many complete requests */ 276 recvs, /* how many complete requests */ 277 bad_xids, /* lookup_rqst didn't find XID */ 278 max_slots; /* max rpc_slots used */ 279 280 unsigned long long req_u, /* average requests on the wire */ 281 bklog_u, /* backlog queue utilization */ 282 sending_u, /* send q utilization */ 283 pending_u; /* pend q utilization */ 284 } stat; 285 286 struct net *xprt_net; 287 const char *servername; 288 const char *address_strings[RPC_DISPLAY_MAX]; 289 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 290 struct dentry *debugfs; /* debugfs directory */ 291 #endif 292 struct rcu_head rcu; 293 const struct xprt_class *xprt_class; 294 struct rpc_sysfs_xprt *xprt_sysfs; 295 bool main; /*mark if this is the 1st transport */ 296 }; 297 298 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 299 /* 300 * Backchannel flags 301 */ 302 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 303 /* buffer in use */ 304 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 305 306 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 307 static inline int bc_prealloc(struct rpc_rqst *req) 308 { 309 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 310 } 311 #else 312 static inline int bc_prealloc(struct rpc_rqst *req) 313 { 314 return 0; 315 } 316 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 317 318 #define XPRT_CREATE_INFINITE_SLOTS (1U) 319 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 320 321 struct xprt_create { 322 int ident; /* XPRT_TRANSPORT identifier */ 323 struct net * net; 324 struct sockaddr * srcaddr; /* optional local address */ 325 struct sockaddr * dstaddr; /* remote peer address */ 326 size_t addrlen; 327 const char *servername; 328 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 329 struct rpc_xprt_switch *bc_xps; 330 unsigned int flags; 331 }; 332 333 struct xprt_class { 334 struct list_head list; 335 int ident; /* XPRT_TRANSPORT identifier */ 336 struct rpc_xprt * (*setup)(struct xprt_create *); 337 struct module *owner; 338 char name[32]; 339 const char * netid[]; 340 }; 341 342 /* 343 * Generic internal transport functions 344 */ 345 struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 346 void xprt_connect(struct rpc_task *task); 347 unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt); 348 void xprt_reconnect_backoff(struct rpc_xprt *xprt, 349 unsigned long init_to); 350 void xprt_reserve(struct rpc_task *task); 351 void xprt_retry_reserve(struct rpc_task *task); 352 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 353 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 354 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 355 void xprt_free_slot(struct rpc_xprt *xprt, 356 struct rpc_rqst *req); 357 void xprt_request_prepare(struct rpc_rqst *req); 358 bool xprt_prepare_transmit(struct rpc_task *task); 359 void xprt_request_enqueue_transmit(struct rpc_task *task); 360 void xprt_request_enqueue_receive(struct rpc_task *task); 361 void xprt_request_wait_receive(struct rpc_task *task); 362 void xprt_request_dequeue_xprt(struct rpc_task *task); 363 bool xprt_request_need_retransmit(struct rpc_task *task); 364 void xprt_transmit(struct rpc_task *task); 365 void xprt_end_transmit(struct rpc_task *task); 366 int xprt_adjust_timeout(struct rpc_rqst *req); 367 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 368 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 369 void xprt_release(struct rpc_task *task); 370 struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); 371 void xprt_put(struct rpc_xprt *xprt); 372 struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 373 unsigned int num_prealloc, 374 unsigned int max_req); 375 void xprt_free(struct rpc_xprt *); 376 void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task); 377 bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req); 378 void xprt_cleanup_ids(void); 379 380 static inline int 381 xprt_enable_swap(struct rpc_xprt *xprt) 382 { 383 return xprt->ops->enable_swap(xprt); 384 } 385 386 static inline void 387 xprt_disable_swap(struct rpc_xprt *xprt) 388 { 389 xprt->ops->disable_swap(xprt); 390 } 391 392 /* 393 * Transport switch helper functions 394 */ 395 int xprt_register_transport(struct xprt_class *type); 396 int xprt_unregister_transport(struct xprt_class *type); 397 int xprt_find_transport_ident(const char *); 398 void xprt_wait_for_reply_request_def(struct rpc_task *task); 399 void xprt_wait_for_reply_request_rtt(struct rpc_task *task); 400 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 401 void xprt_wait_for_buffer_space(struct rpc_xprt *xprt); 402 bool xprt_write_space(struct rpc_xprt *xprt); 403 void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 404 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 405 void xprt_update_rtt(struct rpc_task *task); 406 void xprt_complete_rqst(struct rpc_task *task, int copied); 407 void xprt_pin_rqst(struct rpc_rqst *req); 408 void xprt_unpin_rqst(struct rpc_rqst *req); 409 void xprt_release_rqst_cong(struct rpc_task *task); 410 bool xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req); 411 void xprt_disconnect_done(struct rpc_xprt *xprt); 412 void xprt_force_disconnect(struct rpc_xprt *xprt); 413 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 414 415 bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 416 void xprt_unlock_connect(struct rpc_xprt *, void *); 417 void xprt_release_write(struct rpc_xprt *, struct rpc_task *); 418 419 /* 420 * Reserved bit positions in xprt->state 421 */ 422 #define XPRT_LOCKED (0) 423 #define XPRT_CONNECTED (1) 424 #define XPRT_CONNECTING (2) 425 #define XPRT_CLOSE_WAIT (3) 426 #define XPRT_BOUND (4) 427 #define XPRT_BINDING (5) 428 #define XPRT_CLOSING (6) 429 #define XPRT_OFFLINE (7) 430 #define XPRT_REMOVE (8) 431 #define XPRT_CONGESTED (9) 432 #define XPRT_CWND_WAIT (10) 433 #define XPRT_WRITE_SPACE (11) 434 #define XPRT_SND_IS_COOKIE (12) 435 436 static inline void xprt_set_connected(struct rpc_xprt *xprt) 437 { 438 set_bit(XPRT_CONNECTED, &xprt->state); 439 } 440 441 static inline void xprt_clear_connected(struct rpc_xprt *xprt) 442 { 443 clear_bit(XPRT_CONNECTED, &xprt->state); 444 } 445 446 static inline int xprt_connected(struct rpc_xprt *xprt) 447 { 448 return test_bit(XPRT_CONNECTED, &xprt->state); 449 } 450 451 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 452 { 453 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 454 } 455 456 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 457 { 458 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 459 } 460 461 static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 462 { 463 smp_mb__before_atomic(); 464 clear_bit(XPRT_CONNECTING, &xprt->state); 465 smp_mb__after_atomic(); 466 } 467 468 static inline int xprt_connecting(struct rpc_xprt *xprt) 469 { 470 return test_bit(XPRT_CONNECTING, &xprt->state); 471 } 472 473 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 474 { 475 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 476 } 477 478 static inline void xprt_set_bound(struct rpc_xprt *xprt) 479 { 480 test_and_set_bit(XPRT_BOUND, &xprt->state); 481 } 482 483 static inline int xprt_bound(struct rpc_xprt *xprt) 484 { 485 return test_bit(XPRT_BOUND, &xprt->state); 486 } 487 488 static inline void xprt_clear_bound(struct rpc_xprt *xprt) 489 { 490 clear_bit(XPRT_BOUND, &xprt->state); 491 } 492 493 static inline void xprt_clear_binding(struct rpc_xprt *xprt) 494 { 495 smp_mb__before_atomic(); 496 clear_bit(XPRT_BINDING, &xprt->state); 497 smp_mb__after_atomic(); 498 } 499 500 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 501 { 502 return test_and_set_bit(XPRT_BINDING, &xprt->state); 503 } 504 505 #endif /* _LINUX_SUNRPC_XPRT_H */ 506