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