1 /* 2 * linux/include/linux/sunrpc/xprt.h 3 * 4 * Declarations for the RPC transport interface. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <[email protected]> 7 */ 8 9 #ifndef _LINUX_SUNRPC_XPRT_H 10 #define _LINUX_SUNRPC_XPRT_H 11 12 #include <linux/uio.h> 13 #include <linux/socket.h> 14 #include <linux/in.h> 15 #include <linux/ktime.h> 16 #include <linux/sunrpc/sched.h> 17 #include <linux/sunrpc/xdr.h> 18 #include <linux/sunrpc/msg_prot.h> 19 20 #ifdef __KERNEL__ 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 seq_file; 57 struct svc_serv; 58 struct net; 59 60 /* 61 * This describes a complete RPC request 62 */ 63 struct rpc_rqst { 64 /* 65 * This is the user-visible part 66 */ 67 struct rpc_xprt * rq_xprt; /* RPC client */ 68 struct xdr_buf rq_snd_buf; /* send buffer */ 69 struct xdr_buf rq_rcv_buf; /* recv buffer */ 70 71 /* 72 * This is the private part 73 */ 74 struct rpc_task * rq_task; /* RPC task data */ 75 struct rpc_cred * rq_cred; /* Bound cred */ 76 __be32 rq_xid; /* request XID */ 77 int rq_cong; /* has incremented xprt->cong */ 78 u32 rq_seqno; /* gss seq no. used on req. */ 79 int rq_enc_pages_num; 80 struct page **rq_enc_pages; /* scratch pages for use by 81 gss privacy code */ 82 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ 83 struct list_head rq_list; 84 85 __u32 * rq_buffer; /* XDR encode buffer */ 86 size_t rq_callsize, 87 rq_rcvsize; 88 size_t rq_xmit_bytes_sent; /* total bytes sent */ 89 size_t rq_reply_bytes_recvd; /* total reply bytes */ 90 /* received */ 91 92 struct xdr_buf rq_private_buf; /* The receive buffer 93 * used in the softirq. 94 */ 95 unsigned long rq_majortimeo; /* major 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 */ 103 104 /* 105 * Partial send handling 106 */ 107 u32 rq_bytes_sent; /* Bytes we have sent */ 108 109 ktime_t rq_xtime; /* transmit time stamp */ 110 int rq_ntrans; 111 112 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 113 struct list_head rq_bc_list; /* Callback service list */ 114 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 115 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 116 #endif /* CONFIG_SUNRPC_BACKCHANEL */ 117 }; 118 #define rq_svec rq_snd_buf.head 119 #define rq_slen rq_snd_buf.len 120 121 struct rpc_xprt_ops { 122 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 123 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 124 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 125 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 126 void (*rpcbind)(struct rpc_task *task); 127 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 128 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 129 void * (*buf_alloc)(struct rpc_task *task, size_t size); 130 void (*buf_free)(void *buffer); 131 int (*send_request)(struct rpc_task *task); 132 void (*set_retrans_timeout)(struct rpc_task *task); 133 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 134 void (*release_request)(struct rpc_task *task); 135 void (*close)(struct rpc_xprt *xprt); 136 void (*destroy)(struct rpc_xprt *xprt); 137 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 138 int (*enable_swap)(struct rpc_xprt *xprt); 139 void (*disable_swap)(struct rpc_xprt *xprt); 140 void (*inject_disconnect)(struct rpc_xprt *xprt); 141 int (*bc_setup)(struct rpc_xprt *xprt, 142 unsigned int min_reqs); 143 int (*bc_up)(struct svc_serv *serv, struct net *net); 144 void (*bc_free_rqst)(struct rpc_rqst *rqst); 145 void (*bc_destroy)(struct rpc_xprt *xprt, 146 unsigned int max_reqs); 147 }; 148 149 /* 150 * RPC transport identifiers 151 * 152 * To preserve compatibility with the historical use of raw IP protocol 153 * id's for transport selection, UDP and TCP identifiers are specified 154 * with the previous values. No such restriction exists for new transports, 155 * except that they may not collide with these values (17 and 6, 156 * respectively). 157 */ 158 #define XPRT_TRANSPORT_BC (1 << 31) 159 enum xprt_transports { 160 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 161 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 162 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 163 XPRT_TRANSPORT_RDMA = 256, 164 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 165 XPRT_TRANSPORT_LOCAL = 257, 166 }; 167 168 struct rpc_xprt { 169 atomic_t count; /* Reference count */ 170 struct rpc_xprt_ops * ops; /* transport methods */ 171 172 const struct rpc_timeout *timeout; /* timeout parms */ 173 struct sockaddr_storage addr; /* server address */ 174 size_t addrlen; /* size of server address */ 175 int prot; /* IP protocol */ 176 177 unsigned long cong; /* current congestion */ 178 unsigned long cwnd; /* congestion window */ 179 180 size_t max_payload; /* largest RPC payload size, 181 in bytes */ 182 unsigned int tsh_size; /* size of transport specific 183 header */ 184 185 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 186 struct rpc_wait_queue sending; /* requests waiting to send */ 187 struct rpc_wait_queue pending; /* requests in flight */ 188 struct rpc_wait_queue backlog; /* waiting for slot */ 189 struct list_head free; /* free slots */ 190 unsigned int max_reqs; /* max number of slots */ 191 unsigned int min_reqs; /* min number of slots */ 192 atomic_t num_reqs; /* total slots */ 193 unsigned long state; /* transport state */ 194 unsigned char resvport : 1; /* use a reserved port */ 195 atomic_t swapper; /* we're swapping over this 196 transport */ 197 unsigned int bind_index; /* bind function index */ 198 199 /* 200 * Connection of transports 201 */ 202 unsigned long bind_timeout, 203 reestablish_timeout; 204 unsigned int connect_cookie; /* A cookie that gets bumped 205 every time the transport 206 is reconnected */ 207 208 /* 209 * Disconnection of idle transports 210 */ 211 struct work_struct task_cleanup; 212 struct timer_list timer; 213 unsigned long last_used, 214 idle_timeout; 215 216 /* 217 * Send stuff 218 */ 219 spinlock_t transport_lock; /* lock transport info */ 220 spinlock_t reserve_lock; /* lock slot table */ 221 u32 xid; /* Next XID value to use */ 222 struct rpc_task * snd_task; /* Task blocked in send */ 223 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 224 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 225 struct svc_serv *bc_serv; /* The RPC service which will */ 226 /* process the callback */ 227 int bc_alloc_count; /* Total number of preallocs */ 228 atomic_t bc_free_slots; 229 spinlock_t bc_pa_lock; /* Protects the preallocated 230 * items */ 231 struct list_head bc_pa_list; /* List of preallocated 232 * backchannel rpc_rqst's */ 233 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 234 struct list_head recv; 235 236 struct { 237 unsigned long bind_count, /* total number of binds */ 238 connect_count, /* total number of connects */ 239 connect_start, /* connect start timestamp */ 240 connect_time, /* jiffies waiting for connect */ 241 sends, /* how many complete requests */ 242 recvs, /* how many complete requests */ 243 bad_xids, /* lookup_rqst didn't find XID */ 244 max_slots; /* max rpc_slots used */ 245 246 unsigned long long req_u, /* average requests on the wire */ 247 bklog_u, /* backlog queue utilization */ 248 sending_u, /* send q utilization */ 249 pending_u; /* pend q utilization */ 250 } stat; 251 252 struct net *xprt_net; 253 const char *servername; 254 const char *address_strings[RPC_DISPLAY_MAX]; 255 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 256 struct dentry *debugfs; /* debugfs directory */ 257 atomic_t inject_disconnect; 258 #endif 259 }; 260 261 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 262 /* 263 * Backchannel flags 264 */ 265 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 266 /* buffer in use */ 267 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 268 269 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 270 static inline int bc_prealloc(struct rpc_rqst *req) 271 { 272 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 273 } 274 #else 275 static inline int bc_prealloc(struct rpc_rqst *req) 276 { 277 return 0; 278 } 279 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 280 281 #define XPRT_CREATE_INFINITE_SLOTS (1U) 282 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 283 284 struct xprt_create { 285 int ident; /* XPRT_TRANSPORT identifier */ 286 struct net * net; 287 struct sockaddr * srcaddr; /* optional local address */ 288 struct sockaddr * dstaddr; /* remote peer address */ 289 size_t addrlen; 290 const char *servername; 291 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 292 unsigned int flags; 293 }; 294 295 struct xprt_class { 296 struct list_head list; 297 int ident; /* XPRT_TRANSPORT identifier */ 298 struct rpc_xprt * (*setup)(struct xprt_create *); 299 struct module *owner; 300 char name[32]; 301 }; 302 303 /* 304 * Generic internal transport functions 305 */ 306 struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 307 void xprt_connect(struct rpc_task *task); 308 void xprt_reserve(struct rpc_task *task); 309 void xprt_retry_reserve(struct rpc_task *task); 310 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 311 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 312 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 313 void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 314 bool xprt_prepare_transmit(struct rpc_task *task); 315 void xprt_transmit(struct rpc_task *task); 316 void xprt_end_transmit(struct rpc_task *task); 317 int xprt_adjust_timeout(struct rpc_rqst *req); 318 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 319 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 320 void xprt_release(struct rpc_task *task); 321 void xprt_put(struct rpc_xprt *xprt); 322 struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 323 unsigned int num_prealloc, 324 unsigned int max_req); 325 void xprt_free(struct rpc_xprt *); 326 327 /** 328 * xprt_get - return a reference to an RPC transport. 329 * @xprt: pointer to the transport 330 * 331 */ 332 static inline struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 333 { 334 if (atomic_inc_not_zero(&xprt->count)) 335 return xprt; 336 return NULL; 337 } 338 339 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) 340 { 341 return p + xprt->tsh_size; 342 } 343 344 static inline int 345 xprt_enable_swap(struct rpc_xprt *xprt) 346 { 347 return xprt->ops->enable_swap(xprt); 348 } 349 350 static inline void 351 xprt_disable_swap(struct rpc_xprt *xprt) 352 { 353 xprt->ops->disable_swap(xprt); 354 } 355 356 /* 357 * Transport switch helper functions 358 */ 359 int xprt_register_transport(struct xprt_class *type); 360 int xprt_unregister_transport(struct xprt_class *type); 361 int xprt_load_transport(const char *); 362 void xprt_set_retrans_timeout_def(struct rpc_task *task); 363 void xprt_set_retrans_timeout_rtt(struct rpc_task *task); 364 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 365 void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action); 366 void xprt_write_space(struct rpc_xprt *xprt); 367 void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 368 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 369 void xprt_complete_rqst(struct rpc_task *task, int copied); 370 void xprt_release_rqst_cong(struct rpc_task *task); 371 void xprt_disconnect_done(struct rpc_xprt *xprt); 372 void xprt_force_disconnect(struct rpc_xprt *xprt); 373 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 374 375 bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 376 void xprt_unlock_connect(struct rpc_xprt *, void *); 377 378 /* 379 * Reserved bit positions in xprt->state 380 */ 381 #define XPRT_LOCKED (0) 382 #define XPRT_CONNECTED (1) 383 #define XPRT_CONNECTING (2) 384 #define XPRT_CLOSE_WAIT (3) 385 #define XPRT_BOUND (4) 386 #define XPRT_BINDING (5) 387 #define XPRT_CLOSING (6) 388 #define XPRT_CONGESTED (9) 389 390 static inline void xprt_set_connected(struct rpc_xprt *xprt) 391 { 392 set_bit(XPRT_CONNECTED, &xprt->state); 393 } 394 395 static inline void xprt_clear_connected(struct rpc_xprt *xprt) 396 { 397 clear_bit(XPRT_CONNECTED, &xprt->state); 398 } 399 400 static inline int xprt_connected(struct rpc_xprt *xprt) 401 { 402 return test_bit(XPRT_CONNECTED, &xprt->state); 403 } 404 405 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 406 { 407 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 408 } 409 410 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 411 { 412 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 413 } 414 415 static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 416 { 417 smp_mb__before_atomic(); 418 clear_bit(XPRT_CONNECTING, &xprt->state); 419 smp_mb__after_atomic(); 420 } 421 422 static inline int xprt_connecting(struct rpc_xprt *xprt) 423 { 424 return test_bit(XPRT_CONNECTING, &xprt->state); 425 } 426 427 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 428 { 429 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 430 } 431 432 static inline void xprt_set_bound(struct rpc_xprt *xprt) 433 { 434 test_and_set_bit(XPRT_BOUND, &xprt->state); 435 } 436 437 static inline int xprt_bound(struct rpc_xprt *xprt) 438 { 439 return test_bit(XPRT_BOUND, &xprt->state); 440 } 441 442 static inline void xprt_clear_bound(struct rpc_xprt *xprt) 443 { 444 clear_bit(XPRT_BOUND, &xprt->state); 445 } 446 447 static inline void xprt_clear_binding(struct rpc_xprt *xprt) 448 { 449 smp_mb__before_atomic(); 450 clear_bit(XPRT_BINDING, &xprt->state); 451 smp_mb__after_atomic(); 452 } 453 454 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 455 { 456 return test_and_set_bit(XPRT_BINDING, &xprt->state); 457 } 458 459 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 460 extern unsigned int rpc_inject_disconnect; 461 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 462 { 463 if (!rpc_inject_disconnect) 464 return; 465 if (atomic_dec_return(&xprt->inject_disconnect)) 466 return; 467 atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); 468 xprt->ops->inject_disconnect(xprt); 469 } 470 #else 471 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 472 { 473 } 474 #endif 475 476 #endif /* __KERNEL__*/ 477 478 #endif /* _LINUX_SUNRPC_XPRT_H */ 479