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 33enum rpc_display_format_t { 34 RPC_DISPLAY_ADDR = 0, 35 RPC_DISPLAY_PORT, 36 RPC_DISPLAY_PROTO, 37 RPC_DISPLAY_HEX_ADDR, 38 RPC_DISPLAY_HEX_PORT, 39 RPC_DISPLAY_NETID, 40 RPC_DISPLAY_MAX, 41}; 42 43struct rpc_task; 44struct rpc_xprt; 45struct xprt_class; 46struct seq_file; 47struct svc_serv; 48struct net; 49#include <linux/lwq.h> 50 51/* 52 * This describes a complete RPC request 53 */ 54struct rpc_rqst { 55 /* 56 * This is the user-visible part 57 */ 58 struct rpc_xprt * rq_xprt; /* RPC client */ 59 struct xdr_buf rq_snd_buf; /* send buffer */ 60 struct xdr_buf rq_rcv_buf; /* recv buffer */ 61 62 /* 63 * This is the private part 64 */ 65 struct rpc_task * rq_task; /* RPC task data */ 66 struct rpc_cred * rq_cred; /* Bound cred */ 67 __be32 rq_xid; /* request XID */ 68 int rq_cong; /* has incremented xprt->cong */ 69 u32 rq_seqno; /* gss seq no. used on req. */ 70 int rq_enc_pages_num; 71 struct page **rq_enc_pages; /* scratch pages for use by 72 gss privacy code */ 73 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ 74 75 union { 76 struct list_head rq_list; /* Slot allocation list */ 77 struct rb_node rq_recv; /* Receive queue */ 78 }; 79 80 struct list_head rq_xmit; /* Send queue */ 81 struct list_head rq_xmit2; /* Send queue */ 82 83 void *rq_buffer; /* Call XDR encode buffer */ 84 size_t rq_callsize; 85 void *rq_rbuffer; /* Reply XDR decode buffer */ 86 size_t rq_rcvsize; 87 size_t rq_xmit_bytes_sent; /* total bytes sent */ 88 size_t rq_reply_bytes_recvd; /* total reply bytes */ 89 /* received */ 90 91 struct xdr_buf rq_private_buf; /* The receive buffer 92 * used in the softirq. 93 */ 94 unsigned long rq_majortimeo; /* major timeout alarm */ 95 unsigned long rq_minortimeo; /* minor timeout alarm */ 96 unsigned long rq_timeout; /* Current timeout value */ 97 ktime_t rq_rtt; /* round-trip time */ 98 unsigned int rq_retries; /* # of retries */ 99 unsigned int rq_connect_cookie; 100 /* A cookie used to track the 101 state of the transport 102 connection */ 103 atomic_t rq_pin; 104 105 /* 106 * Partial send handling 107 */ 108 u32 rq_bytes_sent; /* Bytes we have sent */ 109 110 ktime_t rq_xtime; /* transmit time stamp */ 111 int rq_ntrans; 112 113#if defined(CONFIG_SUNRPC_BACKCHANNEL) 114 struct lwq_node rq_bc_list; /* Callback service list */ 115 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 116 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 117#endif /* CONFIG_SUNRPC_BACKCHANEL */ 118}; 119#define rq_svec rq_snd_buf.head 120#define rq_slen rq_snd_buf.len 121 122/* RPC transport layer security policies */ 123enum xprtsec_policies { 124 RPC_XPRTSEC_NONE = 0, 125 RPC_XPRTSEC_TLS_ANON, 126 RPC_XPRTSEC_TLS_X509, 127}; 128 129struct xprtsec_parms { 130 enum xprtsec_policies policy; 131 132 /* authentication material */ 133 key_serial_t cert_serial; 134 key_serial_t privkey_serial; 135}; 136 137struct rpc_xprt_ops { 138 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 139 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 140 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 141 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 142 void (*free_slot)(struct rpc_xprt *xprt, 143 struct rpc_rqst *req); 144 void (*rpcbind)(struct rpc_task *task); 145 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 146 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 147 int (*get_srcaddr)(struct rpc_xprt *xprt, char *buf, 148 size_t buflen); 149 unsigned short (*get_srcport)(struct rpc_xprt *xprt); 150 int (*buf_alloc)(struct rpc_task *task); 151 void (*buf_free)(struct rpc_task *task); 152 int (*prepare_request)(struct rpc_rqst *req, 153 struct xdr_buf *buf); 154 int (*send_request)(struct rpc_rqst *req); 155 void (*abort_send_request)(struct rpc_rqst *req); 156 void (*wait_for_reply_request)(struct rpc_task *task); 157 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 158 void (*release_request)(struct rpc_task *task); 159 void (*close)(struct rpc_xprt *xprt); 160 void (*destroy)(struct rpc_xprt *xprt); 161 void (*set_connect_timeout)(struct rpc_xprt *xprt, 162 unsigned long connect_timeout, 163 unsigned long reconnect_timeout); 164 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 165 int (*enable_swap)(struct rpc_xprt *xprt); 166 void (*disable_swap)(struct rpc_xprt *xprt); 167 void (*inject_disconnect)(struct rpc_xprt *xprt); 168 int (*bc_setup)(struct rpc_xprt *xprt, 169 unsigned int min_reqs); 170 size_t (*bc_maxpayload)(struct rpc_xprt *xprt); 171 unsigned int (*bc_num_slots)(struct rpc_xprt *xprt); 172 void (*bc_free_rqst)(struct rpc_rqst *rqst); 173 void (*bc_destroy)(struct rpc_xprt *xprt, 174 unsigned int max_reqs); 175}; 176 177/* 178 * RPC transport identifiers 179 * 180 * To preserve compatibility with the historical use of raw IP protocol 181 * id's for transport selection, UDP and TCP identifiers are specified 182 * with the previous values. No such restriction exists for new transports, 183 * except that they may not collide with these values (17 and 6, 184 * respectively). 185 */ 186#define XPRT_TRANSPORT_BC (1 << 31) 187enum xprt_transports { 188 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 189 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 190 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 191 XPRT_TRANSPORT_RDMA = 256, 192 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 193 XPRT_TRANSPORT_LOCAL = 257, 194 XPRT_TRANSPORT_TCP_TLS = 258, 195}; 196 197struct rpc_sysfs_xprt; 198struct rpc_xprt { 199 struct kref kref; /* Reference count */ 200 const struct rpc_xprt_ops *ops; /* transport methods */ 201 unsigned int id; /* transport id */ 202 203 const struct rpc_timeout *timeout; /* timeout parms */ 204 struct sockaddr_storage addr; /* server address */ 205 size_t addrlen; /* size of server address */ 206 int prot; /* IP protocol */ 207 208 unsigned long cong; /* current congestion */ 209 unsigned long cwnd; /* congestion window */ 210 211 size_t max_payload; /* largest RPC payload size, 212 in bytes */ 213 214 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 215 struct rpc_wait_queue sending; /* requests waiting to send */ 216 struct rpc_wait_queue pending; /* requests in flight */ 217 struct rpc_wait_queue backlog; /* waiting for slot */ 218 struct list_head free; /* free slots */ 219 unsigned int max_reqs; /* max number of slots */ 220 unsigned int min_reqs; /* min number of slots */ 221 unsigned int num_reqs; /* total slots */ 222 unsigned long state; /* transport state */ 223 unsigned char resvport : 1, /* use a reserved port */ 224 reuseport : 1; /* reuse port on reconnect */ 225 atomic_t swapper; /* we're swapping over this 226 transport */ 227 unsigned int bind_index; /* bind function index */ 228 229 /* 230 * Multipath 231 */ 232 struct list_head xprt_switch; 233 234 /* 235 * Connection of transports 236 */ 237 unsigned long bind_timeout, 238 reestablish_timeout; 239 struct xprtsec_parms xprtsec; 240 unsigned int connect_cookie; /* A cookie that gets bumped 241 every time the transport 242 is reconnected */ 243 244 /* 245 * Disconnection of idle transports 246 */ 247 struct work_struct task_cleanup; 248 struct timer_list timer; 249 unsigned long last_used, 250 idle_timeout, 251 connect_timeout, 252 max_reconnect_timeout; 253 254 /* 255 * Send stuff 256 */ 257 atomic_long_t queuelen; 258 spinlock_t transport_lock; /* lock transport info */ 259 spinlock_t reserve_lock; /* lock slot table */ 260 spinlock_t queue_lock; /* send/receive queue lock */ 261 u32 xid; /* Next XID value to use */ 262 struct rpc_task * snd_task; /* Task blocked in send */ 263 264 struct list_head xmit_queue; /* Send queue */ 265 atomic_long_t xmit_queuelen; 266 267 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 268#if defined(CONFIG_SUNRPC_BACKCHANNEL) 269 struct svc_serv *bc_serv; /* The RPC service which will */ 270 /* process the callback */ 271 unsigned int bc_alloc_max; 272 unsigned int bc_alloc_count; /* Total number of preallocs */ 273 atomic_t bc_slot_count; /* Number of allocated slots */ 274 spinlock_t bc_pa_lock; /* Protects the preallocated 275 * items */ 276 struct list_head bc_pa_list; /* List of preallocated 277 * backchannel rpc_rqst's */ 278#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 279 280 struct rb_root recv_queue; /* Receive queue */ 281 282 struct { 283 unsigned long bind_count, /* total number of binds */ 284 connect_count, /* total number of connects */ 285 connect_start, /* connect start timestamp */ 286 connect_time, /* jiffies waiting for connect */ 287 sends, /* how many complete requests */ 288 recvs, /* how many complete requests */ 289 bad_xids, /* lookup_rqst didn't find XID */ 290 max_slots; /* max rpc_slots used */ 291 292 unsigned long long req_u, /* average requests on the wire */ 293 bklog_u, /* backlog queue utilization */ 294 sending_u, /* send q utilization */ 295 pending_u; /* pend q utilization */ 296 } stat; 297 298 struct net *xprt_net; 299 netns_tracker ns_tracker; 300 const char *servername; 301 const char *address_strings[RPC_DISPLAY_MAX]; 302#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 303 struct dentry *debugfs; /* debugfs directory */ 304#endif 305 struct rcu_head rcu; 306 const struct xprt_class *xprt_class; 307 struct rpc_sysfs_xprt *xprt_sysfs; 308 bool main; /*mark if this is the 1st transport */ 309}; 310 311#if defined(CONFIG_SUNRPC_BACKCHANNEL) 312/* 313 * Backchannel flags 314 */ 315#define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 316 /* buffer in use */ 317#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 318 319#if defined(CONFIG_SUNRPC_BACKCHANNEL) 320static inline int bc_prealloc(struct rpc_rqst *req) 321{ 322 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 323} 324#else 325static inline int bc_prealloc(struct rpc_rqst *req) 326{ 327 return 0; 328} 329#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 330 331#define XPRT_CREATE_INFINITE_SLOTS (1U) 332#define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 333 334struct xprt_create { 335 int ident; /* XPRT_TRANSPORT identifier */ 336 struct net * net; 337 struct sockaddr * srcaddr; /* optional local address */ 338 struct sockaddr * dstaddr; /* remote peer address */ 339 size_t addrlen; 340 const char *servername; 341 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 342 struct rpc_xprt_switch *bc_xps; 343 unsigned int flags; 344 struct xprtsec_parms xprtsec; 345 unsigned long connect_timeout; 346 unsigned long reconnect_timeout; 347}; 348 349struct xprt_class { 350 struct list_head list; 351 int ident; /* XPRT_TRANSPORT identifier */ 352 struct rpc_xprt * (*setup)(struct xprt_create *); 353 struct module *owner; 354 char name[32]; 355 const char * netid[]; 356}; 357 358/* 359 * Generic internal transport functions 360 */ 361struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 362void xprt_connect(struct rpc_task *task); 363unsigned long xprt_reconnect_delay(const struct rpc_xprt *xprt); 364void xprt_reconnect_backoff(struct rpc_xprt *xprt, 365 unsigned long init_to); 366void xprt_reserve(struct rpc_task *task); 367void xprt_retry_reserve(struct rpc_task *task); 368int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 369int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 370void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 371void xprt_free_slot(struct rpc_xprt *xprt, 372 struct rpc_rqst *req); 373bool xprt_prepare_transmit(struct rpc_task *task); 374void xprt_request_enqueue_transmit(struct rpc_task *task); 375int xprt_request_enqueue_receive(struct rpc_task *task); 376void xprt_request_wait_receive(struct rpc_task *task); 377void xprt_request_dequeue_xprt(struct rpc_task *task); 378bool xprt_request_need_retransmit(struct rpc_task *task); 379void xprt_transmit(struct rpc_task *task); 380void xprt_end_transmit(struct rpc_task *task); 381int xprt_adjust_timeout(struct rpc_rqst *req); 382void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 383void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 384void xprt_release(struct rpc_task *task); 385struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); 386void xprt_put(struct rpc_xprt *xprt); 387struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 388 unsigned int num_prealloc, 389 unsigned int max_req); 390void xprt_free(struct rpc_xprt *); 391void xprt_add_backlog(struct rpc_xprt *xprt, struct rpc_task *task); 392bool xprt_wake_up_backlog(struct rpc_xprt *xprt, struct rpc_rqst *req); 393void xprt_cleanup_ids(void); 394 395static inline int 396xprt_enable_swap(struct rpc_xprt *xprt) 397{ 398 return xprt->ops->enable_swap(xprt); 399} 400 401static inline void 402xprt_disable_swap(struct rpc_xprt *xprt) 403{ 404 xprt->ops->disable_swap(xprt); 405} 406 407/* 408 * Transport switch helper functions 409 */ 410int xprt_register_transport(struct xprt_class *type); 411int xprt_unregister_transport(struct xprt_class *type); 412int xprt_find_transport_ident(const char *); 413void xprt_wait_for_reply_request_def(struct rpc_task *task); 414void xprt_wait_for_reply_request_rtt(struct rpc_task *task); 415void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 416void xprt_wait_for_buffer_space(struct rpc_xprt *xprt); 417bool xprt_write_space(struct rpc_xprt *xprt); 418void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 419struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 420void xprt_update_rtt(struct rpc_task *task); 421void xprt_complete_rqst(struct rpc_task *task, int copied); 422void xprt_pin_rqst(struct rpc_rqst *req); 423void xprt_unpin_rqst(struct rpc_rqst *req); 424void xprt_release_rqst_cong(struct rpc_task *task); 425bool xprt_request_get_cong(struct rpc_xprt *xprt, struct rpc_rqst *req); 426void xprt_disconnect_done(struct rpc_xprt *xprt); 427void xprt_force_disconnect(struct rpc_xprt *xprt); 428void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 429 430bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 431void xprt_unlock_connect(struct rpc_xprt *, void *); 432void xprt_release_write(struct rpc_xprt *, struct rpc_task *); 433 434/* 435 * Reserved bit positions in xprt->state 436 */ 437#define XPRT_LOCKED (0) 438#define XPRT_CONNECTED (1) 439#define XPRT_CONNECTING (2) 440#define XPRT_CLOSE_WAIT (3) 441#define XPRT_BOUND (4) 442#define XPRT_BINDING (5) 443#define XPRT_CLOSING (6) 444#define XPRT_OFFLINE (7) 445#define XPRT_REMOVE (8) 446#define XPRT_CONGESTED (9) 447#define XPRT_CWND_WAIT (10) 448#define XPRT_WRITE_SPACE (11) 449#define XPRT_SND_IS_COOKIE (12) 450 451static inline void xprt_set_connected(struct rpc_xprt *xprt) 452{ 453 set_bit(XPRT_CONNECTED, &xprt->state); 454} 455 456static inline void xprt_clear_connected(struct rpc_xprt *xprt) 457{ 458 clear_bit(XPRT_CONNECTED, &xprt->state); 459} 460 461static inline int xprt_connected(struct rpc_xprt *xprt) 462{ 463 return test_bit(XPRT_CONNECTED, &xprt->state); 464} 465 466static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 467{ 468 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 469} 470 471static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 472{ 473 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 474} 475 476static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 477{ 478 smp_mb__before_atomic(); 479 clear_bit(XPRT_CONNECTING, &xprt->state); 480 smp_mb__after_atomic(); 481} 482 483static inline int xprt_connecting(struct rpc_xprt *xprt) 484{ 485 return test_bit(XPRT_CONNECTING, &xprt->state); 486} 487 488static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 489{ 490 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 491} 492 493static inline void xprt_set_bound(struct rpc_xprt *xprt) 494{ 495 test_and_set_bit(XPRT_BOUND, &xprt->state); 496} 497 498static inline int xprt_bound(struct rpc_xprt *xprt) 499{ 500 return test_bit(XPRT_BOUND, &xprt->state); 501} 502 503static inline void xprt_clear_bound(struct rpc_xprt *xprt) 504{ 505 clear_bit(XPRT_BOUND, &xprt->state); 506} 507 508static inline void xprt_clear_binding(struct rpc_xprt *xprt) 509{ 510 smp_mb__before_atomic(); 511 clear_bit(XPRT_BINDING, &xprt->state); 512 smp_mb__after_atomic(); 513} 514 515static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 516{ 517 return test_and_set_bit(XPRT_BINDING, &xprt->state); 518} 519 520void xprt_set_offline_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 521void xprt_set_online_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 522void xprt_delete_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps); 523#endif /* _LINUX_SUNRPC_XPRT_H */ 524