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 <[email protected]> 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 #include <linux/lwq.h> 61 62 /* 63 * This describes a complete RPC request 64 */ 65 struct rpc_rqst { 66 /* 67 * This is the user-visible part 68 */ 69 struct rpc_xprt * rq_xprt; /* RPC client */ 70 struct xdr_buf rq_snd_buf; /* send buffer */ 71 struct xdr_buf rq_rcv_buf; /* recv buffer */ 72 73 /* 74 * This is the private part 75 */ 76 struct rpc_task * rq_task; /* RPC task data */ 77 struct rpc_cred * rq_cred; /* Bound cred */ 78 __be32 rq_xid; /* request XID */ 79 int rq_cong; /* has incremented xprt->cong */ 80 u32 rq_seqno; /* gss seq no. used on req. */ 81 int rq_enc_pages_num; 82 struct page **rq_enc_pages; /* scratch pages for use by 83 gss privacy code */ 84 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ 85 86 union { 87 struct list_head rq_list; /* Slot allocation list */ 88 struct rb_node rq_recv; /* Receive queue */ 89 }; 90 91 struct list_head rq_xmit; /* Send queue */ 92 struct list_head rq_xmit2; /* Send queue */ 93 94 void *rq_buffer; /* Call XDR encode buffer */ 95 size_t rq_callsize; 96 void *rq_rbuffer; /* Reply XDR decode buffer */ 97 size_t rq_rcvsize; 98 size_t rq_xmit_bytes_sent; /* total bytes sent */ 99 size_t rq_reply_bytes_recvd; /* total reply bytes */ 100 /* received */ 101 102 struct xdr_buf rq_private_buf; /* The receive buffer 103 * used in the softirq. 104 */ 105 unsigned long rq_majortimeo; /* major timeout alarm */ 106 unsigned long rq_minortimeo; /* minor timeout alarm */ 107 unsigned long rq_timeout; /* Current timeout value */ 108 ktime_t rq_rtt; /* round-trip time */ 109 unsigned int rq_retries; /* # of retries */ 110 unsigned int rq_connect_cookie; 111 /* A cookie used to track the 112 state of the transport 113 connection */ 114 atomic_t rq_pin; 115 116 /* 117 * Partial send handling 118 */ 119 u32 rq_bytes_sent; /* Bytes we have sent */ 120 121 ktime_t rq_xtime; /* transmit time stamp */ 122 int rq_ntrans; 123 124 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 125 struct lwq_node rq_bc_list; /* Callback service list */ 126 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 127 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 128 #endif /* CONFIG_SUNRPC_BACKCHANEL */ 129 }; 130 #define rq_svec rq_snd_buf.head 131 #define rq_slen rq_snd_buf.len 132 133 /* RPC transport layer security policies */ 134 enum xprtsec_policies { 135 RPC_XPRTSEC_NONE = 0, 136 RPC_XPRTSEC_TLS_ANON, 137 RPC_XPRTSEC_TLS_X509, 138 }; 139 140 struct xprtsec_parms { 141 enum xprtsec_policies policy; 142 143 /* authentication material */ 144 key_serial_t cert_serial; 145 key_serial_t privkey_serial; 146 }; 147 148 struct rpc_xprt_ops { 149 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 150 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 151 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 152 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 153 void (*free_slot)(struct rpc_xprt *xprt, 154 struct rpc_rqst *req); 155 void (*rpcbind)(struct rpc_task *task); 156 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 157 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 158 int (*get_srcaddr)(struct rpc_xprt *xprt, char *buf, 159 size_t buflen); 160 unsigned short (*get_srcport)(struct rpc_xprt *xprt); 161 int (*buf_alloc)(struct rpc_task *task); 162 void (*buf_free)(struct rpc_task *task); 163 int (*prepare_request)(struct rpc_rqst *req, 164 struct xdr_buf *buf); 165 int (*send_request)(struct rpc_rqst *req); 166 void (*wait_for_reply_request)(struct rpc_task *task); 167 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 168 void (*release_request)(struct rpc_task *task); 169 void (*close)(struct rpc_xprt *xprt); 170 void (*destroy)(struct rpc_xprt *xprt); 171 void (*set_connect_timeout)(struct rpc_xprt *xprt, 172 unsigned long connect_timeout, 173 unsigned long reconnect_timeout); 174 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 175 int (*enable_swap)(struct rpc_xprt *xprt); 176 void (*disable_swap)(struct rpc_xprt *xprt); 177 void (*inject_disconnect)(struct rpc_xprt *xprt); 178 int (*bc_setup)(struct rpc_xprt *xprt, 179 unsigned int min_reqs); 180 size_t (*bc_maxpayload)(struct rpc_xprt *xprt); 181 unsigned int (*bc_num_slots)(struct rpc_xprt *xprt); 182 void (*bc_free_rqst)(struct rpc_rqst *rqst); 183 void (*bc_destroy)(struct rpc_xprt *xprt, 184 unsigned int max_reqs); 185 }; 186 187 /* 188 * RPC transport identifiers 189 * 190 * To preserve compatibility with the historical use of raw IP protocol 191 * id's for transport selection, UDP and TCP identifiers are specified 192 * with the previous values. No such restriction exists for new transports, 193 * except that they may not collide with these values (17 and 6, 194 * respectively). 195 */ 196 #define XPRT_TRANSPORT_BC (1 << 31) 197 enum xprt_transports { 198 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 199 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 200 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 201 XPRT_TRANSPORT_RDMA = 256, 202 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 203 XPRT_TRANSPORT_LOCAL = 257, 204 XPRT_TRANSPORT_TCP_TLS = 258, 205 }; 206 207 struct rpc_sysfs_xprt; 208 struct rpc_xprt { 209 struct kref kref; /* Reference count */ 210 const struct rpc_xprt_ops *ops; /* transport methods */ 211 unsigned int id; /* transport id */ 212 213 const struct rpc_timeout *timeout; /* timeout parms */ 214 struct sockaddr_storage addr; /* server address */ 215 size_t addrlen; /* size of server address */ 216 int prot; /* IP protocol */ 217 218 unsigned long cong; /* current congestion */ 219 unsigned long cwnd; /* congestion window */ 220 221 size_t max_payload; /* largest RPC payload size, 222 in bytes */ 223 224 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 225 struct rpc_wait_queue sending; /* requests waiting to send */ 226 struct rpc_wait_queue pending; /* requests in flight */ 227 struct rpc_wait_queue backlog; /* waiting for slot */ 228 struct list_head free; /* free slots */ 229 unsigned int max_reqs; /* max number of slots */ 230 unsigned int min_reqs; /* min number of slots */ 231 unsigned int num_reqs; /* total slots */ 232 unsigned long state; /* transport state */ 233 unsigned char resvport : 1, /* use a reserved port */ 234 reuseport : 1; /* reuse port on reconnect */ 235 atomic_t swapper; /* we're swapping over this 236 transport */ 237 unsigned int bind_index; /* bind function index */ 238 239 /* 240 * Multipath 241 */ 242 struct list_head xprt_switch; 243 244 /* 245 * Connection of transports 246 */ 247 unsigned long bind_timeout, 248 reestablish_timeout; 249 struct xprtsec_parms xprtsec; 250 unsigned int connect_cookie; /* A cookie that gets bumped 251 every time the transport 252 is reconnected */ 253 254 /* 255 * Disconnection of idle transports 256 */ 257 struct work_struct task_cleanup; 258 struct timer_list timer; 259 unsigned long last_used, 260 idle_timeout, 261 connect_timeout, 262 max_reconnect_timeout; 263 264 /* 265 * Send stuff 266 */ 267 atomic_long_t queuelen; 268 spinlock_t transport_lock; /* lock transport info */ 269 spinlock_t reserve_lock; /* lock slot table */ 270 spinlock_t queue_lock; /* send/receive queue lock */ 271 u32 xid; /* Next XID value to use */ 272 struct rpc_task * snd_task; /* Task blocked in send */ 273 274 struct list_head xmit_queue; /* Send queue */ 275 atomic_long_t xmit_queuelen; 276 277 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 278 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 279 struct svc_serv *bc_serv; /* The RPC service which will */ 280 /* process the callback */ 281 unsigned int bc_alloc_max; 282 unsigned int bc_alloc_count; /* Total number of preallocs */ 283 atomic_t bc_slot_count; /* Number of allocated slots */ 284 spinlock_t bc_pa_lock; /* Protects the preallocated 285 * items */ 286 struct list_head bc_pa_list; /* List of preallocated 287 * backchannel rpc_rqst's */ 288 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 289 290 struct rb_root recv_queue; /* Receive queue */ 291 292 struct { 293 unsigned long bind_count, /* total number of binds */ 294 connect_count, /* total number of connects */ 295 connect_start, /* connect start timestamp */ 296 connect_time, /* jiffies waiting for connect */ 297 sends, /* how many complete requests */ 298 recvs, /* how many complete requests */ 299 bad_xids, /* lookup_rqst didn't find XID */ 300 max_slots; /* max rpc_slots used */ 301 302 unsigned long long req_u, /* average requests on the wire */ 303 bklog_u, /* backlog queue utilization */ 304 sending_u, /* send q utilization */ 305 pending_u; /* pend q utilization */ 306 } stat; 307 308 struct net *xprt_net; 309 netns_tracker ns_tracker; 310 const char *servername; 311 const char *address_strings[RPC_DISPLAY_MAX]; 312 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 313 struct dentry *debugfs; /* debugfs directory */ 314 #endif 315 struct rcu_head rcu; 316 const struct xprt_class *xprt_class; 317 struct rpc_sysfs_xprt *xprt_sysfs; 318 bool main; /*mark if this is the 1st transport */ 319 }; 320 321 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 322 /* 323 * Backchannel flags 324 */ 325 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 326 /* buffer in use */ 327 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 328 329 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 330 static inline int bc_prealloc(struct rpc_rqst *req) 331 { 332 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 333 } 334 #else 335 static inline int bc_prealloc(struct rpc_rqst *req) 336 { 337 return 0; 338 } 339 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 340 341 #define XPRT_CREATE_INFINITE_SLOTS (1U) 342 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 343 344 struct xprt_create { 345 int ident; /* XPRT_TRANSPORT identifier */ 346 struct net * net; 347 struct sockaddr * srcaddr; /* optional local address */ 348 struct sockaddr * dstaddr; /* remote peer address */ 349 size_t addrlen; 350 const char *servername; 351 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 352 struct rpc_xprt_switch *bc_xps; 353 unsigned int flags; 354 struct xprtsec_parms xprtsec; 355 unsigned long connect_timeout; 356 unsigned long reconnect_timeout; 357 }; 358 359 struct xprt_class { 360 struct list_head list; 361 int ident; /* XPRT_TRANSPORT identifier */ 362 struct rpc_xprt * (*setup)(struct xprt_create *); 363 struct module *owner; 364 char name[32]; 365 const char * netid[]; 366 }; 367 368 /* 369 * Generic internal transport functions 370 */ 371 struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 372 void xprt_connect(struct rpc_task *task); 373 unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt); 374 void xprt_reconnect_backoff(struct rpc_xprt *xprt, 375 unsigned long init_to); 376 void xprt_reserve(struct rpc_task *task); 377 void xprt_retry_reserve(struct rpc_task *task); 378 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 379 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 380 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 381 void xprt_free_slot(struct rpc_xprt *xprt, 382 struct rpc_rqst *req); 383 bool xprt_prepare_transmit(struct rpc_task *task); 384 void xprt_request_enqueue_transmit(struct rpc_task *task); 385 int xprt_request_enqueue_receive(struct rpc_task *task); 386 void xprt_request_wait_receive(struct rpc_task *task); 387 void xprt_request_dequeue_xprt(struct rpc_task *task); 388 bool xprt_request_need_retransmit(struct rpc_task *task); 389 void xprt_transmit(struct rpc_task *task); 390 void xprt_end_transmit(struct rpc_task *task); 391 int xprt_adjust_timeout(struct rpc_rqst *req); 392 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 393 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 394 void xprt_release(struct rpc_task *task); 395 struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); 396 void xprt_put(struct rpc_xprt *xprt); 397 struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 398 unsigned int num_prealloc, 399 unsigned int max_req); 400 void xprt_free(struct rpc_xprt *); 401 void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task); 402 bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req); 403 void xprt_cleanup_ids(void); 404 405 static inline int 406 xprt_enable_swap(struct rpc_xprt *xprt) 407 { 408 return xprt->ops->enable_swap(xprt); 409 } 410 411 static inline void 412 xprt_disable_swap(struct rpc_xprt *xprt) 413 { 414 xprt->ops->disable_swap(xprt); 415 } 416 417 /* 418 * Transport switch helper functions 419 */ 420 int xprt_register_transport(struct xprt_class *type); 421 int xprt_unregister_transport(struct xprt_class *type); 422 int xprt_find_transport_ident(const char *); 423 void xprt_wait_for_reply_request_def(struct rpc_task *task); 424 void xprt_wait_for_reply_request_rtt(struct rpc_task *task); 425 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 426 void xprt_wait_for_buffer_space(struct rpc_xprt *xprt); 427 bool xprt_write_space(struct rpc_xprt *xprt); 428 void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 429 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 430 void xprt_update_rtt(struct rpc_task *task); 431 void xprt_complete_rqst(struct rpc_task *task, int copied); 432 void xprt_pin_rqst(struct rpc_rqst *req); 433 void xprt_unpin_rqst(struct rpc_rqst *req); 434 void xprt_release_rqst_cong(struct rpc_task *task); 435 bool xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req); 436 void xprt_disconnect_done(struct rpc_xprt *xprt); 437 void xprt_force_disconnect(struct rpc_xprt *xprt); 438 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 439 440 bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 441 void xprt_unlock_connect(struct rpc_xprt *, void *); 442 void xprt_release_write(struct rpc_xprt *, struct rpc_task *); 443 444 /* 445 * Reserved bit positions in xprt->state 446 */ 447 #define XPRT_LOCKED (0) 448 #define XPRT_CONNECTED (1) 449 #define XPRT_CONNECTING (2) 450 #define XPRT_CLOSE_WAIT (3) 451 #define XPRT_BOUND (4) 452 #define XPRT_BINDING (5) 453 #define XPRT_CLOSING (6) 454 #define XPRT_OFFLINE (7) 455 #define XPRT_REMOVE (8) 456 #define XPRT_CONGESTED (9) 457 #define XPRT_CWND_WAIT (10) 458 #define XPRT_WRITE_SPACE (11) 459 #define XPRT_SND_IS_COOKIE (12) 460 461 static inline void xprt_set_connected(struct rpc_xprt *xprt) 462 { 463 set_bit(XPRT_CONNECTED, &xprt->state); 464 } 465 466 static inline void xprt_clear_connected(struct rpc_xprt *xprt) 467 { 468 clear_bit(XPRT_CONNECTED, &xprt->state); 469 } 470 471 static inline int xprt_connected(struct rpc_xprt *xprt) 472 { 473 return test_bit(XPRT_CONNECTED, &xprt->state); 474 } 475 476 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 477 { 478 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 479 } 480 481 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 482 { 483 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 484 } 485 486 static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 487 { 488 smp_mb__before_atomic(); 489 clear_bit(XPRT_CONNECTING, &xprt->state); 490 smp_mb__after_atomic(); 491 } 492 493 static inline int xprt_connecting(struct rpc_xprt *xprt) 494 { 495 return test_bit(XPRT_CONNECTING, &xprt->state); 496 } 497 498 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 499 { 500 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 501 } 502 503 static inline void xprt_set_bound(struct rpc_xprt *xprt) 504 { 505 test_and_set_bit(XPRT_BOUND, &xprt->state); 506 } 507 508 static inline int xprt_bound(struct rpc_xprt *xprt) 509 { 510 return test_bit(XPRT_BOUND, &xprt->state); 511 } 512 513 static inline void xprt_clear_bound(struct rpc_xprt *xprt) 514 { 515 clear_bit(XPRT_BOUND, &xprt->state); 516 } 517 518 static inline void xprt_clear_binding(struct rpc_xprt *xprt) 519 { 520 smp_mb__before_atomic(); 521 clear_bit(XPRT_BINDING, &xprt->state); 522 smp_mb__after_atomic(); 523 } 524 525 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 526 { 527 return test_and_set_bit(XPRT_BINDING, &xprt->state); 528 } 529 530 void xprt_set_offline_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 531 void xprt_set_online_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 532 void xprt_delete_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 533 #endif /* _LINUX_SUNRPC_XPRT_H */ 534