1 /* 2 * linux/include/linux/sunrpc/svc.h 3 * 4 * RPC server declarations. 5 * 6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de> 7 */ 8 9 10 #ifndef SUNRPC_SVC_H 11 #define SUNRPC_SVC_H 12 13 #include <linux/in.h> 14 #include <linux/in6.h> 15 #include <linux/sunrpc/types.h> 16 #include <linux/sunrpc/xdr.h> 17 #include <linux/sunrpc/auth.h> 18 #include <linux/sunrpc/svcauth.h> 19 #include <linux/wait.h> 20 #include <linux/mm.h> 21 22 /* statistics for svc_pool structures */ 23 struct svc_pool_stats { 24 atomic_long_t packets; 25 unsigned long sockets_queued; 26 atomic_long_t threads_woken; 27 atomic_long_t threads_timedout; 28 }; 29 30 /* 31 * 32 * RPC service thread pool. 33 * 34 * Pool of threads and temporary sockets. Generally there is only 35 * a single one of these per RPC service, but on NUMA machines those 36 * services that can benefit from it (i.e. nfs but not lockd) will 37 * have one pool per NUMA node. This optimisation reduces cross- 38 * node traffic on multi-node NUMA NFS servers. 39 */ 40 struct svc_pool { 41 unsigned int sp_id; /* pool id; also node id on NUMA */ 42 spinlock_t sp_lock; /* protects all fields */ 43 struct list_head sp_sockets; /* pending sockets */ 44 unsigned int sp_nrthreads; /* # of threads in pool */ 45 struct list_head sp_all_threads; /* all server threads */ 46 struct svc_pool_stats sp_stats; /* statistics on pool operation */ 47 #define SP_TASK_PENDING (0) /* still work to do even if no 48 * xprt is queued. */ 49 unsigned long sp_flags; 50 } ____cacheline_aligned_in_smp; 51 52 struct svc_serv; 53 54 struct svc_serv_ops { 55 /* Callback to use when last thread exits. */ 56 void (*svo_shutdown)(struct svc_serv *, struct net *); 57 58 /* function for service threads to run */ 59 int (*svo_function)(void *); 60 61 /* queue up a transport for servicing */ 62 void (*svo_enqueue_xprt)(struct svc_xprt *); 63 64 /* set up thread (or whatever) execution context */ 65 int (*svo_setup)(struct svc_serv *, struct svc_pool *, int); 66 67 /* optional module to count when adding threads (pooled svcs only) */ 68 struct module *svo_module; 69 }; 70 71 /* 72 * RPC service. 73 * 74 * An RPC service is a ``daemon,'' possibly multithreaded, which 75 * receives and processes incoming RPC messages. 76 * It has one or more transport sockets associated with it, and maintains 77 * a list of idle threads waiting for input. 78 * 79 * We currently do not support more than one RPC program per daemon. 80 */ 81 struct svc_serv { 82 struct svc_program * sv_program; /* RPC program */ 83 struct svc_stat * sv_stats; /* RPC statistics */ 84 spinlock_t sv_lock; 85 unsigned int sv_nrthreads; /* # of server threads */ 86 unsigned int sv_maxconn; /* max connections allowed or 87 * '0' causing max to be based 88 * on number of threads. */ 89 90 unsigned int sv_max_payload; /* datagram payload size */ 91 unsigned int sv_max_mesg; /* max_payload + 1 page for overheads */ 92 unsigned int sv_xdrsize; /* XDR buffer size */ 93 struct list_head sv_permsocks; /* all permanent sockets */ 94 struct list_head sv_tempsocks; /* all temporary sockets */ 95 int sv_tmpcnt; /* count of temporary sockets */ 96 struct timer_list sv_temptimer; /* timer for aging temporary sockets */ 97 98 char * sv_name; /* service name */ 99 100 unsigned int sv_nrpools; /* number of thread pools */ 101 struct svc_pool * sv_pools; /* array of thread pools */ 102 struct svc_serv_ops *sv_ops; /* server operations */ 103 #if defined(CONFIG_SUNRPC_BACKCHANNEL) 104 struct list_head sv_cb_list; /* queue for callback requests 105 * that arrive over the same 106 * connection */ 107 spinlock_t sv_cb_lock; /* protects the svc_cb_list */ 108 wait_queue_head_t sv_cb_waitq; /* sleep here if there are no 109 * entries in the svc_cb_list */ 110 struct svc_xprt *sv_bc_xprt; /* callback on fore channel */ 111 #endif /* CONFIG_SUNRPC_BACKCHANNEL */ 112 }; 113 114 /* 115 * We use sv_nrthreads as a reference count. svc_destroy() drops 116 * this refcount, so we need to bump it up around operations that 117 * change the number of threads. Horrible, but there it is. 118 * Should be called with the "service mutex" held. 119 */ 120 static inline void svc_get(struct svc_serv *serv) 121 { 122 serv->sv_nrthreads++; 123 } 124 125 /* 126 * Maximum payload size supported by a kernel RPC server. 127 * This is use to determine the max number of pages nfsd is 128 * willing to return in a single READ operation. 129 * 130 * These happen to all be powers of 2, which is not strictly 131 * necessary but helps enforce the real limitation, which is 132 * that they should be multiples of PAGE_SIZE. 133 * 134 * For UDP transports, a block plus NFS,RPC, and UDP headers 135 * has to fit into the IP datagram limit of 64K. The largest 136 * feasible number for all known page sizes is probably 48K, 137 * but we choose 32K here. This is the same as the historical 138 * Linux limit; someone who cares more about NFS/UDP performance 139 * can test a larger number. 140 * 141 * For TCP transports we have more freedom. A size of 1MB is 142 * chosen to match the client limit. Other OSes are known to 143 * have larger limits, but those numbers are probably beyond 144 * the point of diminishing returns. 145 */ 146 #define RPCSVC_MAXPAYLOAD (1*1024*1024u) 147 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD 148 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) 149 150 extern u32 svc_max_payload(const struct svc_rqst *rqstp); 151 152 /* 153 * RPC Requsts and replies are stored in one or more pages. 154 * We maintain an array of pages for each server thread. 155 * Requests are copied into these pages as they arrive. Remaining 156 * pages are available to write the reply into. 157 * 158 * Pages are sent using ->sendpage so each server thread needs to 159 * allocate more to replace those used in sending. To help keep track 160 * of these pages we have a receive list where all pages initialy live, 161 * and a send list where pages are moved to when there are to be part 162 * of a reply. 163 * 164 * We use xdr_buf for holding responses as it fits well with NFS 165 * read responses (that have a header, and some data pages, and possibly 166 * a tail) and means we can share some client side routines. 167 * 168 * The xdr_buf.head kvec always points to the first page in the rq_*pages 169 * list. The xdr_buf.pages pointer points to the second page on that 170 * list. xdr_buf.tail points to the end of the first page. 171 * This assumes that the non-page part of an rpc reply will fit 172 * in a page - NFSd ensures this. lockd also has no trouble. 173 * 174 * Each request/reply pair can have at most one "payload", plus two pages, 175 * one for the request, and one for the reply. 176 * We using ->sendfile to return read data, we might need one extra page 177 * if the request is not page-aligned. So add another '1'. 178 */ 179 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ 180 + 2 + 1) 181 182 static inline u32 svc_getnl(struct kvec *iov) 183 { 184 __be32 val, *vp; 185 vp = iov->iov_base; 186 val = *vp++; 187 iov->iov_base = (void*)vp; 188 iov->iov_len -= sizeof(__be32); 189 return ntohl(val); 190 } 191 192 static inline void svc_putnl(struct kvec *iov, u32 val) 193 { 194 __be32 *vp = iov->iov_base + iov->iov_len; 195 *vp = htonl(val); 196 iov->iov_len += sizeof(__be32); 197 } 198 199 static inline __be32 svc_getu32(struct kvec *iov) 200 { 201 __be32 val, *vp; 202 vp = iov->iov_base; 203 val = *vp++; 204 iov->iov_base = (void*)vp; 205 iov->iov_len -= sizeof(__be32); 206 return val; 207 } 208 209 static inline void svc_ungetu32(struct kvec *iov) 210 { 211 __be32 *vp = (__be32 *)iov->iov_base; 212 iov->iov_base = (void *)(vp - 1); 213 iov->iov_len += sizeof(*vp); 214 } 215 216 static inline void svc_putu32(struct kvec *iov, __be32 val) 217 { 218 __be32 *vp = iov->iov_base + iov->iov_len; 219 *vp = val; 220 iov->iov_len += sizeof(__be32); 221 } 222 223 /* 224 * The context of a single thread, including the request currently being 225 * processed. 226 */ 227 struct svc_rqst { 228 struct list_head rq_all; /* all threads list */ 229 struct rcu_head rq_rcu_head; /* for RCU deferred kfree */ 230 struct svc_xprt * rq_xprt; /* transport ptr */ 231 232 struct sockaddr_storage rq_addr; /* peer address */ 233 size_t rq_addrlen; 234 struct sockaddr_storage rq_daddr; /* dest addr of request 235 * - reply from here */ 236 size_t rq_daddrlen; 237 238 struct svc_serv * rq_server; /* RPC service definition */ 239 struct svc_pool * rq_pool; /* thread pool */ 240 struct svc_procedure * rq_procinfo; /* procedure info */ 241 struct auth_ops * rq_authop; /* authentication flavour */ 242 struct svc_cred rq_cred; /* auth info */ 243 void * rq_xprt_ctxt; /* transport specific context ptr */ 244 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 245 246 size_t rq_xprt_hlen; /* xprt header len */ 247 struct xdr_buf rq_arg; 248 struct xdr_buf rq_res; 249 struct page * rq_pages[RPCSVC_MAXPAGES]; 250 struct page * *rq_respages; /* points into rq_pages */ 251 struct page * *rq_next_page; /* next reply page to use */ 252 struct page * *rq_page_end; /* one past the last page */ 253 254 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ 255 256 __be32 rq_xid; /* transmission id */ 257 u32 rq_prog; /* program number */ 258 u32 rq_vers; /* program version */ 259 u32 rq_proc; /* procedure number */ 260 u32 rq_prot; /* IP protocol */ 261 int rq_cachetype; /* catering to nfsd */ 262 #define RQ_SECURE (0) /* secure port */ 263 #define RQ_LOCAL (1) /* local request */ 264 #define RQ_USEDEFERRAL (2) /* use deferral */ 265 #define RQ_DROPME (3) /* drop current reply */ 266 #define RQ_SPLICE_OK (4) /* turned off in gss privacy 267 * to prevent encrypting page 268 * cache pages */ 269 #define RQ_VICTIM (5) /* about to be shut down */ 270 #define RQ_BUSY (6) /* request is busy */ 271 #define RQ_DATA (7) /* request has data */ 272 unsigned long rq_flags; /* flags field */ 273 274 void * rq_argp; /* decoded arguments */ 275 void * rq_resp; /* xdr'd results */ 276 void * rq_auth_data; /* flavor-specific data */ 277 int rq_auth_slack; /* extra space xdr code 278 * should leave in head 279 * for krb5i, krb5p. 280 */ 281 int rq_reserved; /* space on socket outq 282 * reserved for this request 283 */ 284 285 struct cache_req rq_chandle; /* handle passed to caches for 286 * request delaying 287 */ 288 /* Catering to nfsd */ 289 struct auth_domain * rq_client; /* RPC peer info */ 290 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ 291 struct svc_cacherep * rq_cacherep; /* cache info */ 292 struct task_struct *rq_task; /* service thread */ 293 spinlock_t rq_lock; /* per-request lock */ 294 }; 295 296 #define SVC_NET(svc_rqst) (svc_rqst->rq_xprt->xpt_net) 297 298 /* 299 * Rigorous type checking on sockaddr type conversions 300 */ 301 static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) 302 { 303 return (struct sockaddr_in *) &rqst->rq_addr; 304 } 305 306 static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) 307 { 308 return (struct sockaddr_in6 *) &rqst->rq_addr; 309 } 310 311 static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) 312 { 313 return (struct sockaddr *) &rqst->rq_addr; 314 } 315 316 static inline struct sockaddr_in *svc_daddr_in(const struct svc_rqst *rqst) 317 { 318 return (struct sockaddr_in *) &rqst->rq_daddr; 319 } 320 321 static inline struct sockaddr_in6 *svc_daddr_in6(const struct svc_rqst *rqst) 322 { 323 return (struct sockaddr_in6 *) &rqst->rq_daddr; 324 } 325 326 static inline struct sockaddr *svc_daddr(const struct svc_rqst *rqst) 327 { 328 return (struct sockaddr *) &rqst->rq_daddr; 329 } 330 331 /* 332 * Check buffer bounds after decoding arguments 333 */ 334 static inline int 335 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) 336 { 337 char *cp = (char *)p; 338 struct kvec *vec = &rqstp->rq_arg.head[0]; 339 return cp >= (char*)vec->iov_base 340 && cp <= (char*)vec->iov_base + vec->iov_len; 341 } 342 343 static inline int 344 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) 345 { 346 struct kvec *vec = &rqstp->rq_res.head[0]; 347 char *cp = (char*)p; 348 349 vec->iov_len = cp - (char*)vec->iov_base; 350 351 return vec->iov_len <= PAGE_SIZE; 352 } 353 354 static inline void svc_free_res_pages(struct svc_rqst *rqstp) 355 { 356 while (rqstp->rq_next_page != rqstp->rq_respages) { 357 struct page **pp = --rqstp->rq_next_page; 358 if (*pp) { 359 put_page(*pp); 360 *pp = NULL; 361 } 362 } 363 } 364 365 struct svc_deferred_req { 366 u32 prot; /* protocol (UDP or TCP) */ 367 struct svc_xprt *xprt; 368 struct sockaddr_storage addr; /* where reply must go */ 369 size_t addrlen; 370 struct sockaddr_storage daddr; /* where reply must come from */ 371 size_t daddrlen; 372 struct cache_deferred_req handle; 373 size_t xprt_hlen; 374 int argslen; 375 __be32 args[0]; 376 }; 377 378 /* 379 * List of RPC programs on the same transport endpoint 380 */ 381 struct svc_program { 382 struct svc_program * pg_next; /* other programs (same xprt) */ 383 u32 pg_prog; /* program number */ 384 unsigned int pg_lovers; /* lowest version */ 385 unsigned int pg_hivers; /* highest version */ 386 unsigned int pg_nvers; /* number of versions */ 387 struct svc_version ** pg_vers; /* version array */ 388 char * pg_name; /* service name */ 389 char * pg_class; /* class name: services sharing authentication */ 390 struct svc_stat * pg_stats; /* rpc statistics */ 391 int (*pg_authenticate)(struct svc_rqst *); 392 }; 393 394 /* 395 * RPC program version 396 */ 397 struct svc_version { 398 u32 vs_vers; /* version number */ 399 u32 vs_nproc; /* number of procedures */ 400 struct svc_procedure * vs_proc; /* per-procedure info */ 401 u32 vs_xdrsize; /* xdrsize needed for this version */ 402 403 unsigned int vs_hidden : 1, /* Don't register with portmapper. 404 * Only used for nfsacl so far. */ 405 vs_rpcb_optnl:1;/* Don't care the result of register. 406 * Only used for nfsv4. */ 407 408 /* Override dispatch function (e.g. when caching replies). 409 * A return value of 0 means drop the request. 410 * vs_dispatch == NULL means use default dispatcher. 411 */ 412 int (*vs_dispatch)(struct svc_rqst *, __be32 *); 413 }; 414 415 /* 416 * RPC procedure info 417 */ 418 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 419 struct svc_procedure { 420 svc_procfunc pc_func; /* process the request */ 421 kxdrproc_t pc_decode; /* XDR decode args */ 422 kxdrproc_t pc_encode; /* XDR encode result */ 423 kxdrproc_t pc_release; /* XDR free result */ 424 unsigned int pc_argsize; /* argument struct size */ 425 unsigned int pc_ressize; /* result struct size */ 426 unsigned int pc_count; /* call count */ 427 unsigned int pc_cachetype; /* cache info (NFS) */ 428 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 429 }; 430 431 /* 432 * Mode for mapping cpus to pools. 433 */ 434 enum { 435 SVC_POOL_AUTO = -1, /* choose one of the others */ 436 SVC_POOL_GLOBAL, /* no mapping, just a single global pool 437 * (legacy & UP mode) */ 438 SVC_POOL_PERCPU, /* one pool per cpu */ 439 SVC_POOL_PERNODE /* one pool per numa node */ 440 }; 441 442 struct svc_pool_map { 443 int count; /* How many svc_servs use us */ 444 int mode; /* Note: int not enum to avoid 445 * warnings about "enumeration value 446 * not handled in switch" */ 447 unsigned int npools; 448 unsigned int *pool_to; /* maps pool id to cpu or node */ 449 unsigned int *to_pool; /* maps cpu or node to pool id */ 450 }; 451 452 extern struct svc_pool_map svc_pool_map; 453 454 /* 455 * Function prototypes. 456 */ 457 int svc_rpcb_setup(struct svc_serv *serv, struct net *net); 458 void svc_rpcb_cleanup(struct svc_serv *serv, struct net *net); 459 int svc_bind(struct svc_serv *serv, struct net *net); 460 struct svc_serv *svc_create(struct svc_program *, unsigned int, 461 struct svc_serv_ops *); 462 struct svc_rqst *svc_rqst_alloc(struct svc_serv *serv, 463 struct svc_pool *pool, int node); 464 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, 465 struct svc_pool *pool, int node); 466 void svc_rqst_free(struct svc_rqst *); 467 void svc_exit_thread(struct svc_rqst *); 468 unsigned int svc_pool_map_get(void); 469 void svc_pool_map_put(void); 470 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, 471 struct svc_serv_ops *); 472 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); 473 int svc_pool_stats_open(struct svc_serv *serv, struct file *file); 474 void svc_destroy(struct svc_serv *); 475 void svc_shutdown_net(struct svc_serv *, struct net *); 476 int svc_process(struct svc_rqst *); 477 int bc_svc_process(struct svc_serv *, struct rpc_rqst *, 478 struct svc_rqst *); 479 int svc_register(const struct svc_serv *, struct net *, const int, 480 const unsigned short, const unsigned short); 481 482 void svc_wake_up(struct svc_serv *); 483 void svc_reserve(struct svc_rqst *rqstp, int space); 484 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); 485 char * svc_print_addr(struct svc_rqst *, char *, size_t); 486 487 #define RPC_MAX_ADDRBUFLEN (63U) 488 489 /* 490 * When we want to reduce the size of the reserved space in the response 491 * buffer, we need to take into account the size of any checksum data that 492 * may be at the end of the packet. This is difficult to determine exactly 493 * for all cases without actually generating the checksum, so we just use a 494 * static value. 495 */ 496 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) 497 { 498 svc_reserve(rqstp, space + rqstp->rq_auth_slack); 499 } 500 501 #endif /* SUNRPC_SVC_H */ 502