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