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 overloads_avoided; 33 unsigned long threads_timedout; 34 }; 35 36 /* 37 * 38 * RPC service thread pool. 39 * 40 * Pool of threads and temporary sockets. Generally there is only 41 * a single one of these per RPC service, but on NUMA machines those 42 * services that can benefit from it (i.e. nfs but not lockd) will 43 * have one pool per NUMA node. This optimisation reduces cross- 44 * node traffic on multi-node NUMA NFS servers. 45 */ 46 struct svc_pool { 47 unsigned int sp_id; /* pool id; also node id on NUMA */ 48 spinlock_t sp_lock; /* protects all fields */ 49 struct list_head sp_threads; /* idle server threads */ 50 struct list_head sp_sockets; /* pending sockets */ 51 unsigned int sp_nrthreads; /* # of threads in pool */ 52 struct list_head sp_all_threads; /* all server threads */ 53 int sp_nwaking; /* number of threads woken but not yet active */ 54 struct svc_pool_stats sp_stats; /* statistics on pool operation */ 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 /* Callback to use when last thread 91 * exits. 92 */ 93 94 struct module * sv_module; /* optional module to count when 95 * adding threads */ 96 svc_thread_fn sv_function; /* main function for threads */ 97 #if defined(CONFIG_NFS_V4_1) 98 struct list_head sv_cb_list; /* queue for callback requests 99 * that arrive over the same 100 * connection */ 101 spinlock_t sv_cb_lock; /* protects the svc_cb_list */ 102 wait_queue_head_t sv_cb_waitq; /* sleep here if there are no 103 * entries in the svc_cb_list */ 104 struct svc_xprt *bc_xprt; 105 #endif /* CONFIG_NFS_V4_1 */ 106 }; 107 108 /* 109 * We use sv_nrthreads as a reference count. svc_destroy() drops 110 * this refcount, so we need to bump it up around operations that 111 * change the number of threads. Horrible, but there it is. 112 * Should be called with the BKL held. 113 */ 114 static inline void svc_get(struct svc_serv *serv) 115 { 116 serv->sv_nrthreads++; 117 } 118 119 /* 120 * Maximum payload size supported by a kernel RPC server. 121 * This is use to determine the max number of pages nfsd is 122 * willing to return in a single READ operation. 123 * 124 * These happen to all be powers of 2, which is not strictly 125 * necessary but helps enforce the real limitation, which is 126 * that they should be multiples of PAGE_CACHE_SIZE. 127 * 128 * For UDP transports, a block plus NFS,RPC, and UDP headers 129 * has to fit into the IP datagram limit of 64K. The largest 130 * feasible number for all known page sizes is probably 48K, 131 * but we choose 32K here. This is the same as the historical 132 * Linux limit; someone who cares more about NFS/UDP performance 133 * can test a larger number. 134 * 135 * For TCP transports we have more freedom. A size of 1MB is 136 * chosen to match the client limit. Other OSes are known to 137 * have larger limits, but those numbers are probably beyond 138 * the point of diminishing returns. 139 */ 140 #define RPCSVC_MAXPAYLOAD (1*1024*1024u) 141 #define RPCSVC_MAXPAYLOAD_TCP RPCSVC_MAXPAYLOAD 142 #define RPCSVC_MAXPAYLOAD_UDP (32*1024u) 143 144 extern u32 svc_max_payload(const struct svc_rqst *rqstp); 145 146 /* 147 * RPC Requsts and replies are stored in one or more pages. 148 * We maintain an array of pages for each server thread. 149 * Requests are copied into these pages as they arrive. Remaining 150 * pages are available to write the reply into. 151 * 152 * Pages are sent using ->sendpage so each server thread needs to 153 * allocate more to replace those used in sending. To help keep track 154 * of these pages we have a receive list where all pages initialy live, 155 * and a send list where pages are moved to when there are to be part 156 * of a reply. 157 * 158 * We use xdr_buf for holding responses as it fits well with NFS 159 * read responses (that have a header, and some data pages, and possibly 160 * a tail) and means we can share some client side routines. 161 * 162 * The xdr_buf.head kvec always points to the first page in the rq_*pages 163 * list. The xdr_buf.pages pointer points to the second page on that 164 * list. xdr_buf.tail points to the end of the first page. 165 * This assumes that the non-page part of an rpc reply will fit 166 * in a page - NFSd ensures this. lockd also has no trouble. 167 * 168 * Each request/reply pair can have at most one "payload", plus two pages, 169 * one for the request, and one for the reply. 170 * We using ->sendfile to return read data, we might need one extra page 171 * if the request is not page-aligned. So add another '1'. 172 */ 173 #define RPCSVC_MAXPAGES ((RPCSVC_MAXPAYLOAD+PAGE_SIZE-1)/PAGE_SIZE \ 174 + 2 + 1) 175 176 static inline u32 svc_getnl(struct kvec *iov) 177 { 178 __be32 val, *vp; 179 vp = iov->iov_base; 180 val = *vp++; 181 iov->iov_base = (void*)vp; 182 iov->iov_len -= sizeof(__be32); 183 return ntohl(val); 184 } 185 186 static inline void svc_putnl(struct kvec *iov, u32 val) 187 { 188 __be32 *vp = iov->iov_base + iov->iov_len; 189 *vp = htonl(val); 190 iov->iov_len += sizeof(__be32); 191 } 192 193 static inline __be32 svc_getu32(struct kvec *iov) 194 { 195 __be32 val, *vp; 196 vp = iov->iov_base; 197 val = *vp++; 198 iov->iov_base = (void*)vp; 199 iov->iov_len -= sizeof(__be32); 200 return val; 201 } 202 203 static inline void svc_ungetu32(struct kvec *iov) 204 { 205 __be32 *vp = (__be32 *)iov->iov_base; 206 iov->iov_base = (void *)(vp - 1); 207 iov->iov_len += sizeof(*vp); 208 } 209 210 static inline void svc_putu32(struct kvec *iov, __be32 val) 211 { 212 __be32 *vp = iov->iov_base + iov->iov_len; 213 *vp = val; 214 iov->iov_len += sizeof(__be32); 215 } 216 217 union svc_addr_u { 218 struct in_addr addr; 219 struct in6_addr addr6; 220 }; 221 222 /* 223 * The context of a single thread, including the request currently being 224 * processed. 225 */ 226 struct svc_rqst { 227 struct list_head rq_list; /* idle list */ 228 struct list_head rq_all; /* all threads list */ 229 struct svc_xprt * rq_xprt; /* transport ptr */ 230 struct sockaddr_storage rq_addr; /* peer address */ 231 size_t rq_addrlen; 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 u32 rq_flavor; /* pseudoflavor */ 238 struct svc_cred rq_cred; /* auth info */ 239 void * rq_xprt_ctxt; /* transport specific context ptr */ 240 struct svc_deferred_req*rq_deferred; /* deferred request we are replaying */ 241 int rq_usedeferral; /* use deferral */ 242 243 size_t rq_xprt_hlen; /* xprt header len */ 244 struct xdr_buf rq_arg; 245 struct xdr_buf rq_res; 246 struct page * rq_pages[RPCSVC_MAXPAGES]; 247 struct page * *rq_respages; /* points into rq_pages */ 248 int rq_resused; /* number of pages used for result */ 249 250 struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ 251 252 __be32 rq_xid; /* transmission id */ 253 u32 rq_prog; /* program number */ 254 u32 rq_vers; /* program version */ 255 u32 rq_proc; /* procedure number */ 256 u32 rq_prot; /* IP protocol */ 257 unsigned short 258 rq_secure : 1; /* secure port */ 259 260 union svc_addr_u rq_daddr; /* dest addr of request 261 * - reply from here */ 262 263 void * rq_argp; /* decoded arguments */ 264 void * rq_resp; /* xdr'd results */ 265 void * rq_auth_data; /* flavor-specific data */ 266 267 int rq_reserved; /* space on socket outq 268 * reserved for this request 269 */ 270 271 struct cache_req rq_chandle; /* handle passed to caches for 272 * request delaying 273 */ 274 /* Catering to nfsd */ 275 struct auth_domain * rq_client; /* RPC peer info */ 276 struct auth_domain * rq_gssclient; /* "gss/"-style peer info */ 277 struct svc_cacherep * rq_cacherep; /* cache info */ 278 struct knfsd_fh * rq_reffh; /* Referrence filehandle, used to 279 * determine what device number 280 * to report (real or virtual) 281 */ 282 int rq_splice_ok; /* turned off in gss privacy 283 * to prevent encrypting page 284 * cache pages */ 285 wait_queue_head_t rq_wait; /* synchronization */ 286 struct task_struct *rq_task; /* service thread */ 287 int rq_waking; /* 1 if thread is being woken */ 288 }; 289 290 /* 291 * Rigorous type checking on sockaddr type conversions 292 */ 293 static inline struct sockaddr_in *svc_addr_in(const struct svc_rqst *rqst) 294 { 295 return (struct sockaddr_in *) &rqst->rq_addr; 296 } 297 298 static inline struct sockaddr_in6 *svc_addr_in6(const struct svc_rqst *rqst) 299 { 300 return (struct sockaddr_in6 *) &rqst->rq_addr; 301 } 302 303 static inline struct sockaddr *svc_addr(const struct svc_rqst *rqst) 304 { 305 return (struct sockaddr *) &rqst->rq_addr; 306 } 307 308 /* 309 * Check buffer bounds after decoding arguments 310 */ 311 static inline int 312 xdr_argsize_check(struct svc_rqst *rqstp, __be32 *p) 313 { 314 char *cp = (char *)p; 315 struct kvec *vec = &rqstp->rq_arg.head[0]; 316 return cp >= (char*)vec->iov_base 317 && cp <= (char*)vec->iov_base + vec->iov_len; 318 } 319 320 static inline int 321 xdr_ressize_check(struct svc_rqst *rqstp, __be32 *p) 322 { 323 struct kvec *vec = &rqstp->rq_res.head[0]; 324 char *cp = (char*)p; 325 326 vec->iov_len = cp - (char*)vec->iov_base; 327 328 return vec->iov_len <= PAGE_SIZE; 329 } 330 331 static inline void svc_free_res_pages(struct svc_rqst *rqstp) 332 { 333 while (rqstp->rq_resused) { 334 struct page **pp = (rqstp->rq_respages + 335 --rqstp->rq_resused); 336 if (*pp) { 337 put_page(*pp); 338 *pp = NULL; 339 } 340 } 341 } 342 343 struct svc_deferred_req { 344 u32 prot; /* protocol (UDP or TCP) */ 345 struct svc_xprt *xprt; 346 struct sockaddr_storage addr; /* where reply must go */ 347 size_t addrlen; 348 union svc_addr_u daddr; /* where reply must come from */ 349 struct cache_deferred_req handle; 350 size_t xprt_hlen; 351 int argslen; 352 __be32 args[0]; 353 }; 354 355 /* 356 * List of RPC programs on the same transport endpoint 357 */ 358 struct svc_program { 359 struct svc_program * pg_next; /* other programs (same xprt) */ 360 u32 pg_prog; /* program number */ 361 unsigned int pg_lovers; /* lowest version */ 362 unsigned int pg_hivers; /* lowest version */ 363 unsigned int pg_nvers; /* number of versions */ 364 struct svc_version ** pg_vers; /* version array */ 365 char * pg_name; /* service name */ 366 char * pg_class; /* class name: services sharing authentication */ 367 struct svc_stat * pg_stats; /* rpc statistics */ 368 int (*pg_authenticate)(struct svc_rqst *); 369 }; 370 371 /* 372 * RPC program version 373 */ 374 struct svc_version { 375 u32 vs_vers; /* version number */ 376 u32 vs_nproc; /* number of procedures */ 377 struct svc_procedure * vs_proc; /* per-procedure info */ 378 u32 vs_xdrsize; /* xdrsize needed for this version */ 379 380 unsigned int vs_hidden : 1; /* Don't register with portmapper. 381 * Only used for nfsacl so far. */ 382 383 /* Override dispatch function (e.g. when caching replies). 384 * A return value of 0 means drop the request. 385 * vs_dispatch == NULL means use default dispatcher. 386 */ 387 int (*vs_dispatch)(struct svc_rqst *, __be32 *); 388 }; 389 390 /* 391 * RPC procedure info 392 */ 393 typedef __be32 (*svc_procfunc)(struct svc_rqst *, void *argp, void *resp); 394 struct svc_procedure { 395 svc_procfunc pc_func; /* process the request */ 396 kxdrproc_t pc_decode; /* XDR decode args */ 397 kxdrproc_t pc_encode; /* XDR encode result */ 398 kxdrproc_t pc_release; /* XDR free result */ 399 unsigned int pc_argsize; /* argument struct size */ 400 unsigned int pc_ressize; /* result struct size */ 401 unsigned int pc_count; /* call count */ 402 unsigned int pc_cachetype; /* cache info (NFS) */ 403 unsigned int pc_xdrressize; /* maximum size of XDR reply */ 404 }; 405 406 /* 407 * Function prototypes. 408 */ 409 struct svc_serv *svc_create(struct svc_program *, unsigned int, 410 void (*shutdown)(struct svc_serv *)); 411 struct svc_rqst *svc_prepare_thread(struct svc_serv *serv, 412 struct svc_pool *pool); 413 void svc_exit_thread(struct svc_rqst *); 414 struct svc_serv * svc_create_pooled(struct svc_program *, unsigned int, 415 void (*shutdown)(struct svc_serv *), 416 svc_thread_fn, struct module *); 417 int svc_set_num_threads(struct svc_serv *, struct svc_pool *, int); 418 int svc_pool_stats_open(struct svc_serv *serv, struct file *file); 419 void svc_destroy(struct svc_serv *); 420 int svc_process(struct svc_rqst *); 421 int bc_svc_process(struct svc_serv *, struct rpc_rqst *, 422 struct svc_rqst *); 423 int svc_register(const struct svc_serv *, const int, 424 const unsigned short, const unsigned short); 425 426 void svc_wake_up(struct svc_serv *); 427 void svc_reserve(struct svc_rqst *rqstp, int space); 428 struct svc_pool * svc_pool_for_cpu(struct svc_serv *serv, int cpu); 429 char * svc_print_addr(struct svc_rqst *, char *, size_t); 430 431 #define RPC_MAX_ADDRBUFLEN (63U) 432 433 /* 434 * When we want to reduce the size of the reserved space in the response 435 * buffer, we need to take into account the size of any checksum data that 436 * may be at the end of the packet. This is difficult to determine exactly 437 * for all cases without actually generating the checksum, so we just use a 438 * static value. 439 */ 440 static inline void svc_reserve_auth(struct svc_rqst *rqstp, int space) 441 { 442 int added_space = 0; 443 444 if (rqstp->rq_authop->flavour) 445 added_space = RPC_MAX_AUTH_SIZE; 446 svc_reserve(rqstp, space + added_space); 447 } 448 449 #endif /* SUNRPC_SVC_H */ 450