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