1/* 2 * linux/include/linux/sunrpc/xprt.h 3 * 4 * Declarations for the RPC transport interface. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 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 */ 36struct 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 44enum 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 54struct rpc_task; 55struct rpc_xprt; 56struct seq_file; 57 58/* 59 * This describes a complete RPC request 60 */ 61struct rpc_rqst { 62 /* 63 * This is the user-visible part 64 */ 65 struct rpc_xprt * rq_xprt; /* RPC client */ 66 struct xdr_buf rq_snd_buf; /* send buffer */ 67 struct xdr_buf rq_rcv_buf; /* recv buffer */ 68 69 /* 70 * This is the private part 71 */ 72 struct rpc_task * rq_task; /* RPC task data */ 73 struct rpc_cred * rq_cred; /* Bound cred */ 74 __be32 rq_xid; /* request XID */ 75 int rq_cong; /* has incremented xprt->cong */ 76 u32 rq_seqno; /* gss seq no. used on req. */ 77 int rq_enc_pages_num; 78 struct page **rq_enc_pages; /* scratch pages for use by 79 gss privacy code */ 80 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */ 81 struct list_head rq_list; 82 83 __u32 * rq_buffer; /* XDR encode buffer */ 84 size_t rq_callsize, 85 rq_rcvsize; 86 size_t rq_xmit_bytes_sent; /* total bytes sent */ 87 size_t rq_reply_bytes_recvd; /* total reply bytes */ 88 /* received */ 89 90 struct xdr_buf rq_private_buf; /* The receive buffer 91 * used in the softirq. 92 */ 93 unsigned long rq_majortimeo; /* major timeout alarm */ 94 unsigned long rq_timeout; /* Current timeout value */ 95 ktime_t rq_rtt; /* round-trip time */ 96 unsigned int rq_retries; /* # of retries */ 97 unsigned int rq_connect_cookie; 98 /* A cookie used to track the 99 state of the transport 100 connection */ 101 102 /* 103 * Partial send handling 104 */ 105 u32 rq_bytes_sent; /* Bytes we have sent */ 106 107 ktime_t rq_xtime; /* transmit time stamp */ 108 int rq_ntrans; 109 110#if defined(CONFIG_SUNRPC_BACKCHANNEL) 111 struct list_head rq_bc_list; /* Callback service list */ 112 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */ 113 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */ 114#endif /* CONFIG_SUNRPC_BACKCHANEL */ 115}; 116#define rq_svec rq_snd_buf.head 117#define rq_slen rq_snd_buf.len 118 119struct rpc_xprt_ops { 120 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize); 121 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 122 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task); 123 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task); 124 void (*rpcbind)(struct rpc_task *task); 125 void (*set_port)(struct rpc_xprt *xprt, unsigned short port); 126 void (*connect)(struct rpc_xprt *xprt, struct rpc_task *task); 127 void * (*buf_alloc)(struct rpc_task *task, size_t size); 128 void (*buf_free)(void *buffer); 129 int (*send_request)(struct rpc_task *task); 130 void (*set_retrans_timeout)(struct rpc_task *task); 131 void (*timer)(struct rpc_xprt *xprt, struct rpc_task *task); 132 void (*release_request)(struct rpc_task *task); 133 void (*close)(struct rpc_xprt *xprt); 134 void (*destroy)(struct rpc_xprt *xprt); 135 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq); 136}; 137 138/* 139 * RPC transport identifiers 140 * 141 * To preserve compatibility with the historical use of raw IP protocol 142 * id's for transport selection, UDP and TCP identifiers are specified 143 * with the previous values. No such restriction exists for new transports, 144 * except that they may not collide with these values (17 and 6, 145 * respectively). 146 */ 147#define XPRT_TRANSPORT_BC (1 << 31) 148enum xprt_transports { 149 XPRT_TRANSPORT_UDP = IPPROTO_UDP, 150 XPRT_TRANSPORT_TCP = IPPROTO_TCP, 151 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC, 152 XPRT_TRANSPORT_RDMA = 256, 153 XPRT_TRANSPORT_LOCAL = 257, 154}; 155 156struct rpc_xprt { 157 atomic_t count; /* Reference count */ 158 struct rpc_xprt_ops * ops; /* transport methods */ 159 160 const struct rpc_timeout *timeout; /* timeout parms */ 161 struct sockaddr_storage addr; /* server address */ 162 size_t addrlen; /* size of server address */ 163 int prot; /* IP protocol */ 164 165 unsigned long cong; /* current congestion */ 166 unsigned long cwnd; /* congestion window */ 167 168 size_t max_payload; /* largest RPC payload size, 169 in bytes */ 170 unsigned int tsh_size; /* size of transport specific 171 header */ 172 173 struct rpc_wait_queue binding; /* requests waiting on rpcbind */ 174 struct rpc_wait_queue sending; /* requests waiting to send */ 175 struct rpc_wait_queue pending; /* requests in flight */ 176 struct rpc_wait_queue backlog; /* waiting for slot */ 177 struct list_head free; /* free slots */ 178 unsigned int max_reqs; /* max number of slots */ 179 unsigned int min_reqs; /* min number of slots */ 180 atomic_t num_reqs; /* total slots */ 181 unsigned long state; /* transport state */ 182 unsigned char resvport : 1; /* use a reserved port */ 183 unsigned int swapper; /* we're swapping over this 184 transport */ 185 unsigned int bind_index; /* bind function index */ 186 187 /* 188 * Connection of transports 189 */ 190 unsigned long bind_timeout, 191 reestablish_timeout; 192 unsigned int connect_cookie; /* A cookie that gets bumped 193 every time the transport 194 is reconnected */ 195 196 /* 197 * Disconnection of idle transports 198 */ 199 struct work_struct task_cleanup; 200 struct timer_list timer; 201 unsigned long last_used, 202 idle_timeout; 203 204 /* 205 * Send stuff 206 */ 207 spinlock_t transport_lock; /* lock transport info */ 208 spinlock_t reserve_lock; /* lock slot table */ 209 u32 xid; /* Next XID value to use */ 210 struct rpc_task * snd_task; /* Task blocked in send */ 211 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 212#if defined(CONFIG_SUNRPC_BACKCHANNEL) 213 struct svc_serv *bc_serv; /* The RPC service which will */ 214 /* process the callback */ 215 unsigned int bc_alloc_count; /* Total number of preallocs */ 216 spinlock_t bc_pa_lock; /* Protects the preallocated 217 * items */ 218 struct list_head bc_pa_list; /* List of preallocated 219 * backchannel rpc_rqst's */ 220#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 221 struct list_head recv; 222 223 struct { 224 unsigned long bind_count, /* total number of binds */ 225 connect_count, /* total number of connects */ 226 connect_start, /* connect start timestamp */ 227 connect_time, /* jiffies waiting for connect */ 228 sends, /* how many complete requests */ 229 recvs, /* how many complete requests */ 230 bad_xids, /* lookup_rqst didn't find XID */ 231 max_slots; /* max rpc_slots used */ 232 233 unsigned long long req_u, /* average requests on the wire */ 234 bklog_u, /* backlog queue utilization */ 235 sending_u, /* send q utilization */ 236 pending_u; /* pend q utilization */ 237 } stat; 238 239 struct net *xprt_net; 240 const char *servername; 241 const char *address_strings[RPC_DISPLAY_MAX]; 242#if IS_ENABLED(CONFIG_SUNRPC_DEBUG) 243 struct dentry *debugfs; /* debugfs directory */ 244#endif 245}; 246 247#if defined(CONFIG_SUNRPC_BACKCHANNEL) 248/* 249 * Backchannel flags 250 */ 251#define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */ 252 /* buffer in use */ 253#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 254 255#if defined(CONFIG_SUNRPC_BACKCHANNEL) 256static inline int bc_prealloc(struct rpc_rqst *req) 257{ 258 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state); 259} 260#else 261static inline int bc_prealloc(struct rpc_rqst *req) 262{ 263 return 0; 264} 265#endif /* CONFIG_SUNRPC_BACKCHANNEL */ 266 267#define XPRT_CREATE_INFINITE_SLOTS (1U) 268#define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1) 269 270struct xprt_create { 271 int ident; /* XPRT_TRANSPORT identifier */ 272 struct net * net; 273 struct sockaddr * srcaddr; /* optional local address */ 274 struct sockaddr * dstaddr; /* remote peer address */ 275 size_t addrlen; 276 const char *servername; 277 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */ 278 unsigned int flags; 279}; 280 281struct xprt_class { 282 struct list_head list; 283 int ident; /* XPRT_TRANSPORT identifier */ 284 struct rpc_xprt * (*setup)(struct xprt_create *); 285 struct module *owner; 286 char name[32]; 287}; 288 289/* 290 * Generic internal transport functions 291 */ 292struct rpc_xprt *xprt_create_transport(struct xprt_create *args); 293void xprt_connect(struct rpc_task *task); 294void xprt_reserve(struct rpc_task *task); 295void xprt_retry_reserve(struct rpc_task *task); 296int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 297int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 298void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 299void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task); 300bool xprt_prepare_transmit(struct rpc_task *task); 301void xprt_transmit(struct rpc_task *task); 302void xprt_end_transmit(struct rpc_task *task); 303int xprt_adjust_timeout(struct rpc_rqst *req); 304void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task); 305void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task); 306void xprt_release(struct rpc_task *task); 307void xprt_put(struct rpc_xprt *xprt); 308struct rpc_xprt * xprt_alloc(struct net *net, size_t size, 309 unsigned int num_prealloc, 310 unsigned int max_req); 311void xprt_free(struct rpc_xprt *); 312 313/** 314 * xprt_get - return a reference to an RPC transport. 315 * @xprt: pointer to the transport 316 * 317 */ 318static inline struct rpc_xprt *xprt_get(struct rpc_xprt *xprt) 319{ 320 if (atomic_inc_not_zero(&xprt->count)) 321 return xprt; 322 return NULL; 323} 324 325static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p) 326{ 327 return p + xprt->tsh_size; 328} 329 330/* 331 * Transport switch helper functions 332 */ 333int xprt_register_transport(struct xprt_class *type); 334int xprt_unregister_transport(struct xprt_class *type); 335int xprt_load_transport(const char *); 336void xprt_set_retrans_timeout_def(struct rpc_task *task); 337void xprt_set_retrans_timeout_rtt(struct rpc_task *task); 338void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status); 339void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action); 340void xprt_write_space(struct rpc_xprt *xprt); 341void xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result); 342struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid); 343void xprt_complete_rqst(struct rpc_task *task, int copied); 344void xprt_release_rqst_cong(struct rpc_task *task); 345void xprt_disconnect_done(struct rpc_xprt *xprt); 346void xprt_force_disconnect(struct rpc_xprt *xprt); 347void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie); 348int xs_swapper(struct rpc_xprt *xprt, int enable); 349 350bool xprt_lock_connect(struct rpc_xprt *, struct rpc_task *, void *); 351void xprt_unlock_connect(struct rpc_xprt *, void *); 352 353/* 354 * Reserved bit positions in xprt->state 355 */ 356#define XPRT_LOCKED (0) 357#define XPRT_CONNECTED (1) 358#define XPRT_CONNECTING (2) 359#define XPRT_CLOSE_WAIT (3) 360#define XPRT_BOUND (4) 361#define XPRT_BINDING (5) 362#define XPRT_CLOSING (6) 363#define XPRT_CONGESTED (9) 364 365static inline void xprt_set_connected(struct rpc_xprt *xprt) 366{ 367 set_bit(XPRT_CONNECTED, &xprt->state); 368} 369 370static inline void xprt_clear_connected(struct rpc_xprt *xprt) 371{ 372 clear_bit(XPRT_CONNECTED, &xprt->state); 373} 374 375static inline int xprt_connected(struct rpc_xprt *xprt) 376{ 377 return test_bit(XPRT_CONNECTED, &xprt->state); 378} 379 380static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt) 381{ 382 return test_and_set_bit(XPRT_CONNECTED, &xprt->state); 383} 384 385static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt) 386{ 387 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state); 388} 389 390static inline void xprt_clear_connecting(struct rpc_xprt *xprt) 391{ 392 smp_mb__before_atomic(); 393 clear_bit(XPRT_CONNECTING, &xprt->state); 394 smp_mb__after_atomic(); 395} 396 397static inline int xprt_connecting(struct rpc_xprt *xprt) 398{ 399 return test_bit(XPRT_CONNECTING, &xprt->state); 400} 401 402static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt) 403{ 404 return test_and_set_bit(XPRT_CONNECTING, &xprt->state); 405} 406 407static inline void xprt_set_bound(struct rpc_xprt *xprt) 408{ 409 test_and_set_bit(XPRT_BOUND, &xprt->state); 410} 411 412static inline int xprt_bound(struct rpc_xprt *xprt) 413{ 414 return test_bit(XPRT_BOUND, &xprt->state); 415} 416 417static inline void xprt_clear_bound(struct rpc_xprt *xprt) 418{ 419 clear_bit(XPRT_BOUND, &xprt->state); 420} 421 422static inline void xprt_clear_binding(struct rpc_xprt *xprt) 423{ 424 smp_mb__before_atomic(); 425 clear_bit(XPRT_BINDING, &xprt->state); 426 smp_mb__after_atomic(); 427} 428 429static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt) 430{ 431 return test_and_set_bit(XPRT_BINDING, &xprt->state); 432} 433 434#endif /* __KERNEL__*/ 435 436#endif /* _LINUX_SUNRPC_XPRT_H */ 437