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