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/kref.h> 17 #include <linux/sunrpc/sched.h> 18 #include <linux/sunrpc/xdr.h> 19 #include <linux/sunrpc/msg_prot.h> 20 21 #ifdef __KERNEL__ 22 23 #define RPC_MIN_SLOT_TABLE (2U) 24 #define RPC_DEF_SLOT_TABLE (16U) 25 #define RPC_MAX_SLOT_TABLE_LIMIT (65536U) 26 #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT 27 28 #define RPC_CWNDSHIFT (8U) 29 #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT) 30 #define RPC_INITCWND RPC_CWNDSCALE 31 #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT) 32 #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd) 33 34 /* 35 * This describes a timeout strategy 36 */ 37 struct rpc_timeout { 38 unsigned long to_initval, /* initial timeout */ 39 to_maxval, /* max timeout */ 40 to_increment; /* if !exponential */ 41 unsigned int to_retries; /* max # of retries */ 42 unsigned char to_exponential; 43 }; 44 45 enum rpc_display_format_t { 46 RPC_DISPLAY_ADDR = 0, 47 RPC_DISPLAY_PORT, 48 RPC_DISPLAY_PROTO, 49 RPC_DISPLAY_HEX_ADDR, 50 RPC_DISPLAY_HEX_PORT, 51 RPC_DISPLAY_NETID, 52 RPC_DISPLAY_MAX, 53 }; 54 55 struct rpc_task; 56 struct rpc_xprt; 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 struct list_head rq_list; 85 86 __u32 * rq_buffer; /* XDR encode buffer */ 87 size_t rq_callsize, 88 rq_rcvsize; 89 size_t rq_xmit_bytes_sent; /* total bytes sent */ 90 size_t rq_reply_bytes_recvd; /* total reply bytes */ 91 /* received */ 92 93 struct xdr_buf rq_private_buf; /* The receive buffer 94 * used in the softirq. 95 */ 96 unsigned long rq_majortimeo; /* major timeout alarm */ 97 unsigned long rq_timeout; /* Current timeout value */ 98 ktime_t rq_rtt; /* round-trip time */ 99 unsigned int rq_retries; /* # of retries */ 100 unsigned int rq_connect_cookie; 101 /* A cookie used to track the 102 state of the transport 103 connection */ 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 list_head 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 struct rpc_xprt_ops { 123 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 124 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 125 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 126 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 127 void (*rpcbind)(struct rpc_task *task); 128 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 129 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 130 void * (*buf_alloc)(struct rpc_task *task, size_t size); 131 void (*buf_free)(void *buffer); 132 int (*send_request)(struct rpc_task *task); 133 void (*set_retrans_timeout)(struct rpc_task *task); 134 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 135 void (*release_request)(struct rpc_task *task); 136 void (*close)(struct rpc_xprt *xprt); 137 void (*destroy)(struct rpc_xprt *xprt); 138 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 139 int (*enable_swap)(struct rpc_xprt *xprt); 140 void (*disable_swap)(struct rpc_xprt *xprt); 141 void (*inject_disconnect)(struct rpc_xprt *xprt); 142 int (*bc_setup)(struct rpc_xprt *xprt, 143 unsigned int min_reqs); 144 int (*bc_up)(struct svc_serv *serv, struct net *net); 145 size_t (*bc_maxpayload)(struct rpc_xprt *xprt); 146 void (*bc_free_rqst)(struct rpc_rqst *rqst); 147 void (*bc_destroy)(struct rpc_xprt *xprt, 148 unsigned int max_reqs); 149 }; 150 151 /* 152 * RPC transport identifiers 153 * 154 * To preserve compatibility with the historical use of raw IP protocol 155 * id's for transport selection, UDP and TCP identifiers are specified 156 * with the previous values. No such restriction exists for new transports, 157 * except that they may not collide with these values (17 and 6, 158 * respectively). 159 */ 160 #define XPRT_TRANSPORT_BC (1 << 31) 161 enum xprt_transports { 162 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 163 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 164 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 165 XPRT_TRANSPORT_RDMA = 256, 166 XPRT_TRANSPORT_BC_RDMA = XPRT_TRANSPORT_RDMA | XPRT_TRANSPORT_BC, 167 XPRT_TRANSPORT_LOCAL = 257, 168 }; 169 170 struct rpc_xprt { 171 struct kref kref; /* Reference count */ 172 struct rpc_xprt_ops * ops; /* transport methods */ 173 174 const struct rpc_timeout *timeout; /* timeout parms */ 175 struct sockaddr_storage addr; /* server address */ 176 size_t addrlen; /* size of server address */ 177 int prot; /* IP protocol */ 178 179 unsigned long cong; /* current congestion */ 180 unsigned long cwnd; /* congestion window */ 181 182 size_t max_payload; /* largest RPC payload size, 183 in bytes */ 184 unsigned int tsh_size; /* size of transport specific 185 header */ 186 187 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 188 struct rpc_wait_queue sending; /* requests waiting to send */ 189 struct rpc_wait_queue pending; /* requests in flight */ 190 struct rpc_wait_queue backlog; /* waiting for slot */ 191 struct list_head free; /* free slots */ 192 unsigned int max_reqs; /* max number of slots */ 193 unsigned int min_reqs; /* min number of slots */ 194 atomic_t num_reqs; /* total slots */ 195 unsigned long state; /* transport state */ 196 unsigned char resvport : 1; /* use a reserved port */ 197 atomic_t swapper; /* we're swapping over this 198 transport */ 199 unsigned int bind_index; /* bind function index */ 200 201 /* 202 * Multipath 203 */ 204 struct list_head xprt_switch; 205 206 /* 207 * Connection of transports 208 */ 209 unsigned long bind_timeout, 210 reestablish_timeout; 211 unsigned int connect_cookie; /* A cookie that gets bumped 212 every time the transport 213 is reconnected */ 214 215 /* 216 * Disconnection of idle transports 217 */ 218 struct work_struct task_cleanup; 219 struct timer_list timer; 220 unsigned long last_used, 221 idle_timeout; 222 223 /* 224 * Send stuff 225 */ 226 spinlock_t transport_lock; /* lock transport info */ 227 spinlock_t reserve_lock; /* lock slot table */ 228 u32 xid; /* Next XID value to use */ 229 struct rpc_task * snd_task; /* Task blocked in send */ 230 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 231 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 232 struct svc_serv *bc_serv; /* The RPC service which will */ 233 /* process the callback */ 234 int bc_alloc_count; /* Total number of preallocs */ 235 atomic_t bc_free_slots; 236 spinlock_t bc_pa_lock; /* Protects the preallocated 237 * items */ 238 struct list_head bc_pa_list; /* List of preallocated 239 * backchannel rpc_rqst's */ 240 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 241 struct list_head recv; 242 243 struct { 244 unsigned long bind_count, /* total number of binds */ 245 connect_count, /* total number of connects */ 246 connect_start, /* connect start timestamp */ 247 connect_time, /* jiffies waiting for connect */ 248 sends, /* how many complete requests */ 249 recvs, /* how many complete requests */ 250 bad_xids, /* lookup_rqst didn't find XID */ 251 max_slots; /* max rpc_slots used */ 252 253 unsigned long long req_u, /* average requests on the wire */ 254 bklog_u, /* backlog queue utilization */ 255 sending_u, /* send q utilization */ 256 pending_u; /* pend q utilization */ 257 } stat; 258 259 struct net *xprt_net; 260 const char *servername; 261 const char *address_strings[RPC_DISPLAY_MAX]; 262 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 263 struct dentry *debugfs; /* debugfs directory */ 264 atomic_t inject_disconnect; 265 #endif 266 struct rcu_head rcu; 267 }; 268 269 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 270 /* 271 * Backchannel flags 272 */ 273 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 274 /* buffer in use */ 275 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 276 277 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 278 static inline int bc_prealloc(struct rpc_rqst *req) 279 { 280 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 281 } 282 #else 283 static inline int bc_prealloc(struct rpc_rqst *req) 284 { 285 return 0; 286 } 287 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 288 289 #define XPRT_CREATE_INFINITE_SLOTS (1U) 290 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 291 292 struct xprt_create { 293 int ident; /* XPRT_TRANSPORT identifier */ 294 struct net * net; 295 struct sockaddr * srcaddr; /* optional local address */ 296 struct sockaddr * dstaddr; /* remote peer address */ 297 size_t addrlen; 298 const char *servername; 299 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 300 struct rpc_xprt_switch *bc_xps; 301 unsigned int flags; 302 }; 303 304 struct xprt_class { 305 struct list_head list; 306 int ident; /* XPRT_TRANSPORT identifier */ 307 struct rpc_xprt * (*setup)(struct xprt_create *); 308 struct module *owner; 309 char name[32]; 310 }; 311 312 /* 313 * Generic internal transport functions 314 */ 315 struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 316 void xprt_connect(struct rpc_task *task); 317 void xprt_reserve(struct rpc_task *task); 318 void xprt_retry_reserve(struct rpc_task *task); 319 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 320 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 321 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 322 void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 323 bool xprt_prepare_transmit(struct rpc_task *task); 324 void xprt_transmit(struct rpc_task *task); 325 void xprt_end_transmit(struct rpc_task *task); 326 int xprt_adjust_timeout(struct rpc_rqst *req); 327 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 328 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 329 void xprt_release(struct rpc_task *task); 330 struct rpc_xprt * xprt_get(struct rpc_xprt *xprt); 331 void xprt_put(struct rpc_xprt *xprt); 332 struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 333 unsigned int num_prealloc, 334 unsigned int max_req); 335 void xprt_free(struct rpc_xprt *); 336 337 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) 338 { 339 return p + xprt->tsh_size; 340 } 341 342 static inline int 343 xprt_enable_swap(struct rpc_xprt *xprt) 344 { 345 return xprt->ops->enable_swap(xprt); 346 } 347 348 static inline void 349 xprt_disable_swap(struct rpc_xprt *xprt) 350 { 351 xprt->ops->disable_swap(xprt); 352 } 353 354 /* 355 * Transport switch helper functions 356 */ 357 int xprt_register_transport(struct xprt_class *type); 358 int xprt_unregister_transport(struct xprt_class *type); 359 int xprt_load_transport(const char *); 360 void xprt_set_retrans_timeout_def(struct rpc_task *task); 361 void xprt_set_retrans_timeout_rtt(struct rpc_task *task); 362 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 363 void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action); 364 void xprt_write_space(struct rpc_xprt *xprt); 365 void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 366 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 367 void xprt_complete_rqst(struct rpc_task *task, int copied); 368 void xprt_release_rqst_cong(struct rpc_task *task); 369 void xprt_disconnect_done(struct rpc_xprt *xprt); 370 void xprt_force_disconnect(struct rpc_xprt *xprt); 371 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 372 373 bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 374 void xprt_unlock_connect(struct rpc_xprt *, void *); 375 376 /* 377 * Reserved bit positions in xprt->state 378 */ 379 #define XPRT_LOCKED (0) 380 #define XPRT_CONNECTED (1) 381 #define XPRT_CONNECTING (2) 382 #define XPRT_CLOSE_WAIT (3) 383 #define XPRT_BOUND (4) 384 #define XPRT_BINDING (5) 385 #define XPRT_CLOSING (6) 386 #define XPRT_CONGESTED (9) 387 388 static inline void xprt_set_connected(struct rpc_xprt *xprt) 389 { 390 set_bit(XPRT_CONNECTED, &xprt->state); 391 } 392 393 static inline void xprt_clear_connected(struct rpc_xprt *xprt) 394 { 395 clear_bit(XPRT_CONNECTED, &xprt->state); 396 } 397 398 static inline int xprt_connected(struct rpc_xprt *xprt) 399 { 400 return test_bit(XPRT_CONNECTED, &xprt->state); 401 } 402 403 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 404 { 405 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 406 } 407 408 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 409 { 410 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 411 } 412 413 static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 414 { 415 smp_mb__before_atomic(); 416 clear_bit(XPRT_CONNECTING, &xprt->state); 417 smp_mb__after_atomic(); 418 } 419 420 static inline int xprt_connecting(struct rpc_xprt *xprt) 421 { 422 return test_bit(XPRT_CONNECTING, &xprt->state); 423 } 424 425 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 426 { 427 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 428 } 429 430 static inline void xprt_set_bound(struct rpc_xprt *xprt) 431 { 432 test_and_set_bit(XPRT_BOUND, &xprt->state); 433 } 434 435 static inline int xprt_bound(struct rpc_xprt *xprt) 436 { 437 return test_bit(XPRT_BOUND, &xprt->state); 438 } 439 440 static inline void xprt_clear_bound(struct rpc_xprt *xprt) 441 { 442 clear_bit(XPRT_BOUND, &xprt->state); 443 } 444 445 static inline void xprt_clear_binding(struct rpc_xprt *xprt) 446 { 447 smp_mb__before_atomic(); 448 clear_bit(XPRT_BINDING, &xprt->state); 449 smp_mb__after_atomic(); 450 } 451 452 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 453 { 454 return test_and_set_bit(XPRT_BINDING, &xprt->state); 455 } 456 457 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 458 extern unsigned int rpc_inject_disconnect; 459 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 460 { 461 if (!rpc_inject_disconnect) 462 return; 463 if (atomic_dec_return(&xprt->inject_disconnect)) 464 return; 465 atomic_set(&xprt->inject_disconnect, rpc_inject_disconnect); 466 xprt->ops->inject_disconnect(xprt); 467 } 468 #else 469 static inline void xprt_inject_disconnect(struct rpc_xprt *xprt) 470 { 471 } 472 #endif 473 474 #endif /* __KERNEL__*/ 475 476 #endif /* _LINUX_SUNRPC_XPRT_H */ 477